Acoustic signal output device

Abstract

The acoustic signal output device has a drive unit and a housing that accommodates the drive unit therein. Here, the acoustic signal emitted from the drive unit to one side is used as a first acoustic signal, and the acoustic signal emitted from the drive unit to the other side is used as a second acoustic signal. A wall portion of the housing is provided with a single or a plurality of first sound holes for leading out a first sound signal to the outside, and a single or a plurality of second sound holes for leading out a second sound signal to the outside. In addition, the attenuation rate of the first acoustic signal at a second point farther from the acoustic signal output device than the first point, with a predetermined first point at which the first acoustic signal arrives as a reference, is less than or equal to a predetermined value that is less than the attenuation rate due to airborne propagation. Alternatively, the amount of attenuation of the first acoustic signal at a second location based on the first location is greater than or equal to a predetermined value that is greater than the amount of attenuation caused by airborne propagation.

Description

Technical Field

[0001] The present invention relates to an acoustic signal output device, in particular to an acoustic signal output device which does not seal the external auditory canal. Background Art

[0002] In recent years, the burden on the ears caused by wearing earphones and headphones has become a problem. As a device to reduce the burden on the ears, open-type earphones and headphones that do not block the external auditory canal are known.

[0003] Prior art literature

[0004] Non-patent literature

[0005] Non-Patent Literature 1: “WHAT ARE OPEN-EAR HEADPHONES?”, [online], Bose Corporation, [retrieved on September 13, 2021], Internet <https: / / www.bose.com / en_us / better_with_bose / open-ear-headphones.html> Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, open-type earphones and headphones have a problem that sound leaks out to the surroundings. This problem is not limited to open-type earphones and headphones, but is a common problem in sound signal output devices that do not seal the external auditory canal.

[0008] The present invention has been made in view of the above-mentioned point, and an object of the present invention is to provide an acoustic signal output device that does not seal the external auditory canal and can suppress sound leakage to the surroundings.

[0009] Means for solving problems

[0010] Provided is an acoustic signal output device having a drive unit and a housing that accommodates the drive unit. Here, an acoustic signal emitted from the drive unit to one side is referred to as a first acoustic signal, and an acoustic signal emitted from the drive unit to the other side is referred to as a second acoustic signal. A single or multiple first sound holes for exporting the first acoustic signal to the outside, and a single or multiple second sound holes for exporting the second acoustic signal to the outside are provided on the wall of the housing. In addition, the device is designed so that when the first acoustic signal is emitted from the first sound hole and the second acoustic signal is emitted from the second sound hole, the attenuation rate of the first acoustic signal at a second location farther from the acoustic signal output device than the first location based on a predetermined first location where the first acoustic signal arrives becomes less than a predetermined value of the attenuation rate caused by air propagation of the acoustic signal at the second location based on the first location, or the device is designed so that the attenuation amount of the first acoustic signal at the second location based on the first location becomes greater than a predetermined value of the attenuation amount caused by air propagation of the acoustic signal at the second location based on the first location.

[0011] Effects of the Invention

[0012] According to this structure, it is possible to suppress sound leakage to the surroundings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a transparent perspective view illustrating the structure of the sound signal output device according to the first embodiment.

[0014] Figure 2A It is a perspective plan view illustrating the structure of the acoustic signal output device according to the first embodiment. Figure 2B It is a perspective front view illustrating the structure of the acoustic signal output device according to the first embodiment. Figure 2C It is a bottom view illustrating the structure of the acoustic signal output device according to the first embodiment.

[0015] Figure 3A yes Figure 2B 2BA-2BA cross-sectional view. Figure 3B yes Figure 2A 2A-2A cross-sectional view. Figure 3C yes Figure 2B 2BC-2BC cross-sectional view.

[0016] Figure 4 It is a schematic diagram for illustrating the arrangement of the sound holes.

[0017] Figure 5A This is a diagram for illustrating a usage state of the sound signal output device according to the first embodiment. Figure 5B This is a diagram for illustrating observation conditions of an acoustic signal emitted from the acoustic signal output device according to the first embodiment.

[0018] Figure 6 It is an example of Figure 5B Graph showing the frequency characteristics of an acoustic signal observed at position P1.

[0019] Figure 7 It is an example of Figure 5B Graph showing the frequency characteristics of the acoustic signal observed at position P2.

[0020] Figure 8 This is a graph illustrating the difference between the acoustic signal observed at position P1 and the acoustic signal observed at position P2 .

[0021] Fig. 9A as well as Fig. 9B : is a graph illustrating the relationship between the area ratio of the sound holes and the sound leakage.

[0022] Fig. 10A It is a front view for illustrating the arrangement of the sound holes. Fig. 10B It is a schematic diagram for illustrating the arrangement of the sound holes.

[0023] Fig.11A It is a front view for illustrating the arrangement of the sound holes. Fig. 11B It is a schematic diagram for illustrating the arrangement of the sound holes.

[0024] FIG. 12A to FIG. 12C It is a front view for illustrating a modification of the arrangement of the sound holes.

[0025] Fig.13A as well as Fig. 13B It is a perspective plan view for illustrating a modified example of the arrangement of the sound holes.

[0026] Fig.14A as well as Fig. 14B It is a schematic diagram for illustrating a modified example of the arrangement of the sound holes.

[0027] Fig.15A It is a perspective front view for illustrating a modified example of the arrangement of the sound holes. Fig. 15B It is a cross-sectional view for illustrating a modified example of the arrangement of the sound holes and a modified example of the distance between the driver unit and the housing.

[0028] FIG. 16A to FIG. 16C This is a cross-sectional view for illustrating a modified example of the acoustic signal output device according to the first embodiment.

[0029] Fig.17 It is relatively Figure 5B Graph showing the frequency characteristics of an acoustic signal observed at position P1.

[0030] Fig.18 It is an example of Figure 5BGraph showing the frequency characteristics of the acoustic signal observed at position P2.

[0031] Fig.19 This is a graph illustrating the difference between the acoustic signal observed at position P1 and the acoustic signal observed at position P2 .

[0032] Fig. 20A This is a diagram for illustrating the relationship between the acoustic signal AC1 (positive phase signal) emitted to the outside from the first sound hole and the acoustic signal AC2 (negative phase signal) emitted to the outside from the second sound hole. Fig. 20B This diagram is used to illustrate the relationship between the phase difference between the sound signal AC1 (positive phase signal) emitted from the first sound hole to the outside and the sound signal AC2 (negative phase signal) emitted from the second sound hole to the outside and the frequencies of the sound signals AC1 and AC2 when the distance between the first sound hole and the second sound hole is 1.5 cm. Fig. 20C This diagram is used to illustrate the relationship between the maximum value of the sum of the magnitudes of the acoustic signal AC1 (positive phase signal) and the acoustic signal AC2 (negative phase signal) and the frequencies of the acoustic signals AC1 and AC2 observed at a position 15 cm away from the acoustic signal output device when the distance between the first sound hole and the second sound hole is 1.5 cm.

[0033] Fig.21A This is a diagram for illustrating a case where the sound signal output device is modeled as an enclosure. Fig.21B is used to illustrate the resonance frequency f determined based on the Helmholtz resonance of the housing. H A graph showing the relationship between [Hz] and the magnitude of the acoustic signal AC2 (anti-phase signal) in the casing. Fig. 21C This is a diagram for illustrating the relationship between the difference in phase of the acoustic signal AC2 (anti-phase signal) emitted from the second sound hole to the outside with respect to the phase of the acoustic signal AC2 (anti-phase signal) emitted from the driver unit and the frequency of the acoustic signal AC2 (anti-phase signal).

[0034] Fig.22A It is a schematic diagram for explaining the state of acoustic signals AC1 and AC2 observed at position P2. Fig. 22B This is used to illustrate that when the distance between the first sound hole and the second sound hole is 1.5 cm, the resonance frequency f determined based on the Helmholtz resonance of the housing is appropriately adjusted. H A graph showing the relationship between the phase difference between the acoustic signal AC1 (positive phase signal) emitted from the first sound hole and the acoustic signal AC2 (negative phase signal) emitted from the second sound hole and the frequencies of the acoustic signals AC1 and AC2 in the case of [Hz]. Fig. 22CThis is used to illustrate that when the distance between the first sound hole and the second sound hole is 1.5 cm, the resonance frequency f determined based on the Helmholtz resonance of the housing is appropriately adjusted. H A graph showing the relationship between the maximum value of the sum of the magnitudes of acoustic signal AC1 (positive phase signal) and acoustic signal AC2 (negative phase signal) observed at a position 15 cm away from the acoustic signal output device and the frequencies of the acoustic signals AC1 and AC2 in the case of [Hz].

[0035] Fig.23A : is a diagram that models the relationship between the first sound hole, the second sound hole, and the position P2. In this example, the first sound hole and the second sound hole are separated by a distance D. pn . Fig. 23B is an example of a delay φ for suppressing the phase difference between the acoustic signal AC1 and the acoustic signal AC2 at P2. c When the acoustic signal AC2 is provided (with φ c (withφ c )) and not provided (no φ c (withoutφ c )) is a graph showing the relationship between the phase difference and frequency of the acoustic signals AC1 and AC2 observed at position P2.

[0036] Fig.24A It is a schematic diagram for explaining the state of acoustic signals AC1 and AC2 observed at position P2. Fig. 24B This is a diagram for illustrating the relationship between frequency and phase characteristics.

[0037] FIG. 25A to FIG. 25C is used to explain a modified example of the sound signal output device Figure 2A A modified example of the 2A-2A cross-sectional view.

[0038] FIG. 26A to FIG. 26C is used to explain a modified example of the sound signal output device Figure 2A A modified example of the 2A-2A cross-sectional view.

[0039] FIG. 27A to FIG. 27C is used to explain a modified example of the sound signal output device Figure 2A A modified example of the 2A-2A cross-sectional view.

[0040] Fig.28A as well as Fig.28B is used to explain a modified example of the sound signal output device Figure 2A A modified example of the 2A-2A cross-sectional view.

[0041] Fig.29A as well as Fig.29B is used to explain a modified example of the sound signal output device Figure 2AA modified example of the 2A-2A cross-sectional view.

[0042] Fig. 30A as well as Fig. 30B is used to explain a modified example of the sound signal output device Figure 2A A modified example of the 2A-2A cross-sectional view.

[0043] Fig.31A This is a sound signal output device with different total opening areas of the sound holes. Figure 5B Graph showing the frequency characteristics of an acoustic signal observed at position P1. Fig.31B The present invention is an example of an acoustic signal output device with different total opening areas of sound holes. Figure 5B Graph showing the frequency characteristics of the acoustic signal observed at position P2. Fig.31C : is a graph illustrating the difference between the acoustic signal observed at position P1 and the acoustic signal observed at position P2 for the acoustic signal output devices having different total opening areas of the sound holes.

[0044] Fig.32A It is a sound signal output device for different volumes of the internal space of the shell, and compares Figure 5B Graph showing the frequency characteristics of an acoustic signal observed at position P1. Fig.32B The present invention is an example of an acoustic signal output device with different volumes of the internal space of the housing. Figure 5B Graph showing the frequency characteristics of the acoustic signal observed at position P2. Fig.32C : is a graph illustrating the difference between the acoustic signal observed at position P1 and the acoustic signal observed at position P2 for the acoustic signal output devices having different volumes of the internal space of the casing.

[0045] Fig.33A The present invention compares the acoustic signal output device of the embodiment (baseline: with a housing) and the open type (without a housing) acoustic signal output device. Figure 5B Graph showing the frequency characteristics of an acoustic signal observed at position P1. Fig.33B The present invention is an example of an audio signal output device according to an embodiment and an open type audio signal output device. Figure 5B Graph showing the frequency characteristics of the acoustic signal observed at position P2. Fig.33C 3 is a graph illustrating the difference between the acoustic signal observed at position P1 and the acoustic signal observed at position P2 for the acoustic signal output device according to the embodiment and the open-type acoustic signal output device.

[0046] FIG. 34A to FIG. 34C is used to explain a modified example of the sound signal output device Figure 2A A modified example of the 2A-2A cross-sectional view.

[0047] FIG. 35A to FIG. 35C It is a modified example of the end view taken along line 2A-2A in FIG. 2 for explaining a modified example of the acoustic signal output device.

[0048] Fig.36A and Fig.36B It is a modified example of the end view taken along line 2A-2A in FIG. 2 for explaining a modified example of the acoustic signal output device.

[0049] Fig.37A This is a graph comparing the sound pressure levels at position P2 of the acoustic signal AC1 at each frequency for diaphragms having different thicknesses. Fig.37B This is a graph comparing the sound pressure levels at position P2 of the acoustic signal AC2 at various frequencies for diaphragms having different thicknesses. Fig.37C This is a graph comparing the sound pressure levels at position P2 of the acoustic signal after the acoustic signal AC1 at each frequency is canceled out by the acoustic signal AC2 for diaphragms having different thicknesses.

[0050] Fig.38A This is a graph comparing the sound pressure levels at position P2 of the acoustic signal AC1 at each frequency for diaphragms having different thicknesses. Fig.38B This is a graph comparing the sound pressure levels at position P2 of the acoustic signal AC2 at various frequencies for diaphragms having different thicknesses. Fig.38C This is a graph comparing the sound pressure levels at position P2 of the acoustic signal after the acoustic signal AC1 at each frequency is canceled out by the acoustic signal AC2 for diaphragms having different thicknesses.

[0051] Fig.39A This is a graph comparing the phases of the acoustic signal AC1 at various frequencies for diaphragms having different thicknesses. Fig.39B This is a graph comparing the phase of the acoustic signal AC2 at each frequency for diaphragms having different thicknesses. Fig.39C This is a graph comparing the phases of acoustic signals when acoustic signal AC1 is canceled out by acoustic signal AC2 at various frequencies for diaphragms having different thicknesses.

[0052] Fig.40 It is a transparent perspective view illustrating the structure of the sound signal output device according to the second embodiment.

[0053] Fig.41A It is a perspective plan view illustrating the structure of the acoustic signal output device according to the second embodiment. Fig.41B It is a perspective front view illustrating the structure of the acoustic signal output device according to the first embodiment. Fig.41C It is a bottom view illustrating the structure of the acoustic signal output device according to the first embodiment.

[0054] Fig.42A yes Fig.41B 21A-21A cross-sectional view. Fig.42B yes Fig.41A 21B-21B cross-sectional view.

[0055] Fig.43A as well as Fig.43B This is a diagram for illustrating a usage state of the sound signal output device according to the second embodiment.

[0056] Fig.44 It is a transparent perspective view illustrating a modification of the acoustic signal output device according to the second embodiment.

[0057] Fig.45A It is a perspective plan view illustrating a modification of the acoustic signal output device according to the second embodiment. Fig.45B It is a perspective front view illustrating a modification of the acoustic signal output device according to the second embodiment. Fig.45C It is a bottom view illustrating a modification of the acoustic signal output device according to the second embodiment.

[0058] Fig.46 yes Fig.45B 25A-25A cross-sectional view.

[0059] Fig.47 It is a perspective view illustrating the structure of the sound signal output device according to the third embodiment.

[0060] Fig.48 It is a transparent perspective view illustrating the structure of the sound signal output device according to the third embodiment.

[0061] Fig.49 It is a schematic diagram for illustrating the arrangement of the sound holes.

[0062] FIG. 50A to FIG. 50C It is a block diagram for illustrating the configuration of a circuit unit.

[0063] Fig.51 This is a diagram for illustrating a usage state of the sound signal output device according to the third embodiment.

[0064] Fig.52A It is a perspective view illustrating a modification of the acoustic signal output device according to the third embodiment. Fig.52B It is a schematic diagram for illustrating a modified example of the arrangement of the sound holes.

[0065] Fig.53A It is a transparent perspective view illustrating a modification of the acoustic signal output device according to the third embodiment. Fig.53B It is a diagram illustrating a modification of the sound signal output device according to the third embodiment.

[0066] Fig.54AIt is a diagram for illustrating the configuration of an acoustic signal output device according to a fourth embodiment. Fig.54B It is a diagram for illustrating a modification of the sound signal output device according to the fourth embodiment.

[0067] Fig.55A It is a perspective front view for illustrating the structure of the acoustic signal output device according to the fifth embodiment. Fig.55B It is a perspective plan view for illustrating the structure of the sound signal output device according to the fifth embodiment. Fig.55C It is a perspective right side view for illustrating the structure of the sound signal output device according to the fifth embodiment.

[0068] Fig.56A It is a plan view illustrating a fixing portion according to a fifth embodiment. Fig.56B It is a right side view illustrating a fixing portion according to the fifth embodiment. Fig.56C It is a front view illustrating a fixing portion according to a fifth embodiment. Fig.56D yes Fig.56A 36A-36A cross-sectional view.

[0069] Fig.57A It is a perspective front view for illustrating a modification of the acoustic signal output device according to the fifth embodiment. Fig.57B It is a perspective plan view for illustrating a modified example of the sound signal output device according to the fifth embodiment. Fig.57C It is a perspective right side view for illustrating a modification of the sound signal output device according to the fifth embodiment.

[0070] Fig.58 It is a front view for illustrating a modification of the acoustic signal output device according to the fifth embodiment.

[0071] Fig.59A as well as Fig.59B It is a front view for illustrating a modification of the acoustic signal output device according to the fifth embodiment.

[0072] Fig.60A It is a plan view for illustrating a modified example of the acoustic signal output device according to the fifth embodiment. Fig.60B It is a schematic diagram for illustrating a modified example of the arrangement of the sound holes.

[0073] Fig.61A It is a plan view for illustrating a modified example of the acoustic signal output device according to the fifth embodiment. Fig.61B It is a schematic diagram for illustrating a modified example of the arrangement of the sound holes.

[0074] Fig.62 It is a perspective front view for illustrating the structure of the acoustic signal output device according to the fifth embodiment.

[0075] Fig.63AIt is a rear view for illustrating the structure of the acoustic signal output device according to the fifth embodiment. Fig.63B yes Fig.63A 43A-43A cross-sectional view.

[0076] Fig.64 It is a perspective front view for illustrating a modification of the acoustic signal output device according to the fifth embodiment.

[0077] Fig.65 It is a perspective front view for illustrating a modification of the acoustic signal output device according to the fifth embodiment.

[0078] Fig.66A It is a perspective front view for illustrating a modification of the acoustic signal output device according to the fifth embodiment. Fig.66B It is a perspective bottom view for illustrating a modification of the acoustic signal output device according to the fifth embodiment. Fig.66C It is a plan view for illustrating a modified example of the acoustic signal output device according to the fifth embodiment.

[0079] Fig.67A as well as Fig.67B It is a schematic diagram for illustrating a modified example of the arrangement of the sound holes.

[0080] Fig.68A as well as Fig.68B It is a schematic diagram for illustrating a modified example of the arrangement of the sound holes.

[0081] Fig.69A It is a front view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.69B It is a perspective view for illustrating a modified example of the sound signal output device according to the sixth embodiment.

[0082] Fig.70A It is a perspective view for illustrating a modified example of the sound signal output device according to the sixth embodiment. Fig.70B It is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment.

[0083] Fig.71A It is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment. Fig.71B It is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment.

[0084] Fig.72A It is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment. Fig.72B It is a transparent perspective view for illustrating a modified example of the sound signal output device according to the sixth embodiment.

[0085] Fig.73AIt is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment.

[0086] Fig.73B It is a right side view for illustrating a modification of the acoustic signal output device according to the sixth embodiment.

[0087] Fig.73C It is a front view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.73D It is a rear view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.73E It is a front view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0088] Fig.74A It is a perspective view for illustrating a modified example of the sound signal output device according to the sixth embodiment. Fig.74B It is a perspective view for illustrating a modified example of the sound signal output device according to the sixth embodiment. Fig.74C It is a perspective view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0089] Fig.75A as well as Fig.75B It is a front view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0090] Fig.76A It is a front view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.76B It is a rear view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.76C It is a front view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0091] Fig.77A It is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment.

[0092] Fig.77B It is a right side view for illustrating a modification of the acoustic signal output device according to the sixth embodiment.

[0093] Fig.77C It is a front view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.77D It is a rear view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.77E It is a front view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0094] Fig.78AIt is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment. Fig.78B It is a front view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.78C It is a rear view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.78D It is a front view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0095] Fig.79A It is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment. Fig.79B It is a front view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.79C It is a rear view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.79D It is a front view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0096] Fig.80A It is a left side view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.80B It is a front view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.80C It is a front view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0097] Fig.81A It is a plan view for illustrating a modified example of the acoustic signal output device according to the sixth embodiment. Fig.81B It is a right side view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.81C It is a front view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.81D It is a rear view for illustrating a modification of the acoustic signal output device according to the sixth embodiment. Fig.81E It is a front view for illustrating a usage state of a modification of the sound signal output device according to the sixth embodiment.

[0098] Fig.82A as well as Fig.82B It is a schematic diagram for illustrating a modification of the acoustic signal output device according to the sixth embodiment.

[0099] Fig.83A as well as Fig.83B It is a schematic diagram for illustrating a modification of the acoustic signal output device according to the sixth embodiment.

[0100] Fig.84A as well as Fig.84BIt is a schematic diagram for illustrating a modification of the acoustic signal output device according to the sixth embodiment.

[0101] Figures 85A to 85C It is a schematic diagram for illustrating a modification of the acoustic signal output device according to the sixth embodiment. DETAILED DESCRIPTION

[0102] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0103] [First embodiment]

[0104] First, a first embodiment of the present invention will be described.

[0105] <Structure>

[0106] The sound signal output device 10 of the present embodiment is a device for sound listening that is worn without sealing the external auditory canal of the user (for example, open-type earphones, headphones, etc.). Figure 1 , FIG. 2A to FIG. 2C as well as FIG. 3A to FIG. 3C As illustrated in FIG. 1 , the sound signal output device 10 of the present embodiment includes a drive unit 11 that converts an output signal (an electric signal representing a sound signal) output from a playback device into a sound signal and outputs the converted signal, and a housing 12 that accommodates the drive unit 11 therein.

[0107] <Drive unit 11>

[0108] The drive unit (speaker drive unit) 11 is a device (a device having a speaker function) that emits (displays) an acoustic signal AC1 (first acoustic signal) based on an input output signal to one side (D1 direction side), and emits an acoustic signal AC2 (second acoustic signal) which is an inverted signal (phase inversion signal) of the acoustic signal AC1 or an approximate signal of the inverted signal to the other side (D2 direction side). That is, the acoustic signal emitted from the drive unit 11 to one side (D1 direction side) is referred to as the acoustic signal AC1 (first acoustic signal), and the acoustic signal emitted from the drive unit 11 to the other side (D2 direction side) is referred to as the acoustic signal AC2 (second acoustic signal). For example, the drive unit 11 includes a vibration plate 113 that emits an acoustic signal AC1 from one surface 113a to the D1 direction side by vibration, and emits an acoustic signal AC2 from the other surface 113b to the D2 direction side by the same vibration. Figure 2B). The driving unit 11 of this example vibrates based on the input output signal through the vibration plate 113, and releases the acoustic signal AC1 from the surface 111 on one side to the D1 direction side, and releases the acoustic signal AC2 which is the inverted signal of the acoustic signal AC1 or an approximate signal of the inverted signal from the side 112 on the other side to the D2 direction side. That is, the acoustic signal AC2 is an acoustic signal that is incidentally released along with the release of the acoustic signal AC1. In addition, the D2 direction (the other side) is, for example, the opposite direction of the D1 direction (one side), but the D2 direction does not need to be strictly the opposite direction of the D1 direction, as long as the D2 direction is different from the D1 direction. The relationship between one side (D1 direction) and the other side (D2 direction) depends on the type and shape of the driving unit 11. In addition, depending on the type and shape of the driving unit 11, sometimes the acoustic signal AC2 strictly becomes the inverted signal of the acoustic signal AC1, and sometimes the acoustic signal AC2 becomes an approximate signal of the inverted signal of the acoustic signal AC1. For example, the approximate signal of the inverted signal of the acoustic signal AC1 may be (1) a signal obtained by shifting the phase of the inverted signal of the acoustic signal AC1, (2) a signal obtained by changing (amplifying or attenuating) the amplitude of the inverted signal of the acoustic signal AC1, or (3) a signal obtained by shifting the phase of the inverted signal of the acoustic signal AC1 and further changing the amplitude. The phase difference between the inverted signal of the acoustic signal AC1 and its approximate signal is preferably less than δ1% of one cycle of the inverted signal of the acoustic signal AC1. Examples of δ1% are 1%, 3%, 5%, 10%, 20%, etc. In addition, the difference between the amplitude of the inverted signal of the acoustic signal AC1 and the amplitude of its approximate signal is preferably less than δ2% of the amplitude of the inverted signal of the acoustic signal AC1. Examples of δ2% are 1%, 3%, 5%, 10%, 20%, etc. In addition, as the form of the driving unit 11, a dynamic type, a balanced armature type, a hybrid type of a dynamic type and a balanced armature type, a capacitor type, etc. can be exemplified. In addition, the shapes of the drive unit 11 and the vibration plate 113 are not limited. In this embodiment, in order to simplify the description, an example is shown in which the outer shape of the drive unit 11 is a roughly cylindrical shape with two end faces, and the vibration plate 113 is a roughly disc shape, but this does not limit the present invention. For example, the outer shape of the drive unit 11 may also be a rectangular parallelepiped shape, and the vibration plate 113 may also be a dome shape. In addition, examples of acoustic signals are sounds such as music, sound, effect sound, and ambient sound.

[0109] <Casing 12>

[0110] The housing 12 is a hollow component having a wall portion on the outside, and accommodates the drive unit 11 inside. For example, the drive unit 11 is fixed to the end portion on the D1 direction side inside the housing 12. However, this does not limit the present invention. The shape of the housing 12 is also not limited. For example, the shape of the housing 12 is preferably rotationally symmetrical (linearly symmetrical) or approximately rotationally symmetrical about an axis A1 extending in the D1 direction. Thus, it is easy to set a sound hole 123a (described in detail later) so that the deviation of the energy of the sound emitted from the housing 12 in each direction becomes smaller. As a result, it is easy to reduce sound leakage uniformly in all directions. For example, the housing 12 has a wall portion 121, i.e., a first end face, arranged on one side (D1 direction side) of the drive unit 11, a wall portion 122, i.e., a second end face, arranged on the other side (D2 direction side) of the drive unit 11, and a wall portion 123, i.e., a side face, which surrounds a space sandwiched by the first end face and the second end face with the axis A1 passing through the first end face and the second end face as the center ( Figure 2B , Figure 3B ). In the present embodiment, in order to simplify the description, an example is shown in which the shell 12 is a roughly cylindrical shape with two end faces. For example, the interval between the wall portion 121 and the wall portion 122 is 10 mm, and the wall portions 121 and 122 are circular with a radius of 10 mm. However, these are examples and do not limit the present invention. For example, the shell 12 can be a roughly dome-shaped shape with a wall portion at the end, or a hollow roughly cubic shape, or other three-dimensional shapes. In addition, the material constituting the shell 12 is not limited. The shell 12 can be composed of a rigid body such as a synthetic resin or metal, or it can be composed of an elastic body such as rubber.

[0111] <Sound holes 121a, 123a>

[0112] The wall of the housing 12 is provided with: a sound hole 121a (first sound hole) that guides the acoustic signal AC1 (first acoustic signal) emitted from the driver unit 11 to the outside; and a sound hole 123a (second sound hole) that guides the acoustic signal AC2 (second acoustic signal) emitted from the driver unit 11 to the outside. The sound holes 121a and 123a are, for example, through holes that penetrate the wall of the housing 12, but this does not limit the present invention. As long as the acoustic signal AC1 and the acoustic signal AC2 can be respectively guided to the outside, the sound holes 121a and 123a may not be through holes.

[0113] The acoustic signal AC1 emitted from the sound hole 121a reaches the external auditory canal of the user and is heard by the user. On the other hand, an acoustic signal AC2 which is an inverted signal of the acoustic signal AC1 or a signal approximating the inverted signal is emitted from the sound hole 123a. A portion of the acoustic signal AC2 cancels a portion of the acoustic signal AC1 emitted from the sound hole 121a (leakage component). That is, by emitting the acoustic signal AC1 (first acoustic signal) from the sound hole 121a (first sound hole) and emitting the acoustic signal AC2 (second acoustic signal) from the sound hole 123a (second sound hole), the attenuation rate η of the acoustic signal AC1 (first acoustic signal) at the position P2 (second position) based on the position P1 (first position) can be reduced to 11 becomes a predetermined value η th Next, the attenuation amount η of the acoustic signal AC1 (first acoustic signal) at the position P2 (second position) based on the position P1 (first position) can be set to 12 becomes a predetermined value ω th Here, the position P1 (first position) is a predetermined position at which the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) reaches. On the other hand, the position P2 (second position) is a predetermined position farther from the acoustic signal output device 10 than the position P1 (first position). The predetermined value η th is the attenuation rate η of an arbitrary or specific acoustic signal (sound) caused by air propagation at position P2 (second position) relative to position P1 (first position) as a reference. 21 A smaller value (lower value). In addition, the predetermined value ω th is the attenuation η caused by air propagation of an arbitrary or specific acoustic signal (sound) at position P2 (second position) relative to position P1 (first position) as a reference. 22 That is, the acoustic signal output device 10 of the present embodiment is designed so that the attenuation rate η 11 is less than the decay rate η 21 The predetermined value η th Below, or designed to be attenuation η 12 is greater than the attenuation η 22 The predetermined value ω th In addition, the acoustic signal AC1 is propagated through the air from the position P1 to the position P2, and is attenuated by the air propagation and the acoustic signal AC2. Attenuation rate η 11 The attenuation amount η is the ratio of the magnitude AMP2(AC1) of the acoustic signal AC1 at position P2, which is attenuated by air propagation and the acoustic signal AC2, to the magnitude AMP1(AC1) of the acoustic signal AC1 at position P1 (AMP2(AC1) / AMP1(AC1)). 12is the difference between the magnitude AMP1(AC1) and the magnitude AMP2(AC1) (|AMP1(AC1)-AMP2(AC1)|). On the other hand, without considering the acoustic signal AC2, any or specific acoustic signal AC transmitted through the air from position P1 to position P2 ar The attenuation is not due to the acoustic signal AC2 but due to air propagation. Attenuation rate η 21 is the acoustic signal AC at position P2 which is attenuated by air propagation (not attenuated by the acoustic signal AC2) ar Size of AMP2(AC ar ) relative to the acoustic signal AC at position P1 ar Size of AMP1(AC ar ) ratio (AMP2(AC ar ) / AMP1(AC ar )). In addition, the attenuation η 22 Is the size of AMP1 (AC ar ) and size AMP2(AC ar ) difference (|AMP1(AC ar )-AMP2(AC ar )|). In addition, examples of the magnitude of an acoustic signal include the sound pressure of an acoustic signal or the energy of an acoustic signal. In addition, a "leakage component" refers to, for example, a component of the acoustic signal AC1 emitted from the sound hole 121a that is highly likely to reach an area other than the user wearing the acoustic signal output device 10 (for example, a person other than the user wearing the acoustic signal output device 10). For example, a "leakage component" refers to a component of the acoustic signal AC1 that propagates in a direction other than the direction D1. For example, the direct wave of the acoustic signal AC1 is mainly emitted from the sound hole 121a, and the direct wave of the second acoustic signal is mainly emitted from the second sound hole. A portion of the direct wave (direct wave) of the acoustic signal AC1 emitted from the sound hole 121a (leakage component) is canceled out by interfering with at least a portion of the direct wave of the acoustic signal AC2 emitted from the sound hole 123a. However, this does not limit the present invention, and the cancellation may also occur in areas other than the direct wave. That is, a sound leakage component which is at least one of the direct wave and the reflected wave of the acoustic signal AC1 emitted from the sound hole 121a may be cancelled by at least one of the direct wave and the reflected wave of the acoustic signal AC2 emitted from the sound hole 123a.

[0114] The arrangement structure of the sound holes 121a and 123a is illustrated.

[0115] The sound hole 121a (first sound hole) of the present embodiment is provided in the area AR1 (first area) of the wall portion 121 arranged on one side of the driver unit 11 (the side where the acoustic signal AC1 is emitted, i.e., the side in the direction D1) ( Figure 1 , Figure 2A , Figure 2B , Figure 3B ). That is, the sound hole 121a opens toward the D1 direction (first direction) along the axis A1. In addition, the sound hole 123a (second sound hole) of the present embodiment is provided in the area AR3 of the wall portion 123 which is connected to the area AR1 (first area) of the wall portion 121 of the housing 12 and the area AR2 (second area) of the wall portion 122 arranged on the D2 direction side (the side on which the sound signal AC2 is emitted, i.e., the other side) of the drive unit 11. That is, if the direction between the D1 direction (first direction) and the direction opposite to the D1 direction is set to the D12 direction (second direction) ( Figure 3B ), the sound hole 121a (first sound hole) is arranged on the D1 direction side (first direction side) of the housing 12, and the sound hole 123a (second sound hole) is arranged on the D12 direction side (second direction side) of the housing 12. For example, when the housing 12 has a wall portion 121, i.e., a first end face, arranged on one side (D1 direction side) of the driver unit 11, a wall portion 122, i.e., a second end face, arranged on the other side (D2 direction side) of the driver unit 11, and a wall portion 123, i.e., a side face, surrounding a space sandwiched by the first end face and the second end face with the axis A1 along the emission direction (D1 direction) of the acoustic signal AC1 passing through the first end face and the second end face as the center ( Figure 2B , Figure 3B ), the sound hole 121a (first sound hole) is provided on the first end surface, and the sound hole 123a (second sound hole) is provided on the side surface. In addition, in the present embodiment, no sound hole is provided on the wall portion 122 side of the housing 12. This is because if a sound hole is provided on the wall portion 122 side of the housing 12, the sound pressure level of the acoustic signal AC2 emitted from the housing 12 exceeds the level required to offset the sound leakage component of the acoustic signal AC1, and the excess is perceived as sound leakage.

[0116] like Figure 2AAs shown in the examples in FIG. 1 and FIG. 2 , the sound hole 121a of the present embodiment is arranged on or near the axis A1 along the emission direction (D1 direction) of the acoustic signal AC1. The axis A1 of the present embodiment passes through the center of the area AR1 (first area) of the wall portion 121 arranged on one side (D1 direction side) of the driving unit 11 of the housing 12 or near the center. For example, the axis A1 is an axis that passes through the central area of ​​the housing 12 and extends in the D1 direction. That is, the sound hole 121a of the present embodiment is arranged at the central position of the area AR1 of the wall portion 121 of the housing 12. In the present embodiment, in order to simplify the description, an example is shown in which the shape of the edge of the open end of the sound hole 121a is a circle (the open end is circular). The radius of such a sound hole 121a is, for example, 3.5 mm. However, this does not limit the present invention. For example, the shape of the edge of the open end of the sound hole 121a may also be other shapes such as an ellipse, a quadrilateral, a triangle, etc. In addition, the open end of the sound hole 121a may also be a mesh shape. In other words, the open end of the sound hole 121a may also be composed of a plurality of holes. In addition, in the present embodiment, in order to simplify the description, an example is shown in which one sound hole 121a is provided in the area AR1 (first area) of the wall portion 121 of the housing 12. However, this does not limit the present invention. For example, two or more sound holes 121a may be provided in the area AR1 (first area) of the wall portion 121 of the housing 12.

[0117] The sound hole 123a (second sound hole) of the present embodiment is preferably arranged in consideration of the following viewpoints, for example.

[0118] (1) From the perspective of position: the sound hole 123 a is disposed so that the propagation path of the acoustic signal AC2 emitted from the sound hole 123 a overlaps the propagation path of the leakage sound component of the acoustic signal AC1 to be canceled.

[0119] (2) Area perspective: Depending on the opening area of ​​the sound hole 123a, the propagation area of ​​the acoustic signal AC2 emitted from the sound hole 123a and the frequency characteristics of the housing 12 differ. In addition, the frequency characteristics of the housing 12 affect the frequency characteristics of the acoustic signal AC2 emitted from the sound hole 123a, that is, the amplitude at each frequency. Considering the propagation area and frequency characteristics of the acoustic signal AC2 emitted from such a sound hole 123a, the opening area of ​​the sound hole 123a is determined so that the leakage sound component is offset by the acoustic signal AC2 emitted from the sound hole 123a in the area where the leakage sound component is to be offset.

[0120] From the above viewpoints, for example, the sound hole 123a (second sound hole) is preferably configured as follows.

[0121] For example, Figure 2B , Figure 3A , Figure 3CAs shown in the example, the sound holes 123a (second sound holes) of the present embodiment are preferably provided in plurality along a circumference (circle) C1, which is centered on the axis A1 along the emission direction of the acoustic signal AC1 (first acoustic signal). When the plurality of sound holes 123a are provided along the circumference C1, the acoustic signal AC2 is emitted radially (radially centered on the axis A1) from the sound holes 123a to the outside. Here, the sound leakage component of the acoustic signal AC1 is also emitted radially (radially centered on the axis A1) from the sound holes 121a to the outside. Therefore, by providing the plurality of sound holes 123a along the circumference C1, the sound leakage component of the acoustic signal AC1 can be appropriately offset by the acoustic signal AC2. In the present embodiment, for the sake of simplicity of description, an example is shown in which the plurality of sound holes 123a are provided on the circumference C1. However, the plurality of sound holes 123a only need to be provided along the circumference C1, and all the sound holes 123a do not need to be strictly arranged on the circumference C1.

[0122] Furthermore, it is preferable that, in the case where the circumference C1 is equally divided into a plurality of unit arc regions, the sum of the opening areas of the sound holes 123a (second sound holes) provided along the first arc region as any one of the unit arc regions is the same as or substantially the same as the sum of the opening areas of the sound holes 123a (second sound holes) provided along the second arc region as any one of the unit arc regions other than the first arc region. Figure 4As shown in the example, when the circumference C1 is equally divided into four unit arc areas C1-1, ..., C1-4, the sum of the opening areas of the sound holes 123a (second sound holes) arranged along the first arc area (for example, the unit arc area C1-1) which is any one of the unit arc areas C1-1, ..., C1-4 is the same or approximately the same as the sum of the opening areas of the sound holes 123a (second sound holes) arranged along the second arc area (for example, the unit arc area C1-2) which is any one of the unit arc areas other than the first arc area. In addition, here, in order to simplify the description, an example is shown in which the circumference C1 is equally divided into four unit arc areas C1-1, ..., C1-4, but this does not limit the present invention. In addition, "α1 is approximately the same as α2" means that the difference between α1 and α2 is less than β% of α1. Examples of β% are 3%, 5%, 10%, etc. Thus, the sound pressure distribution of the acoustic signal AC2 emitted from the sound hole 123a arranged along the first circular arc area and the sound pressure distribution of the acoustic signal AC2 emitted from the sound hole 123a arranged along the second circular arc area are point-symmetrical or substantially point-symmetrical with respect to the axis A1. Preferably, the sum of the opening areas of the sound holes 123a (second sound holes) arranged along each unit circular arc area is the same or substantially the same for each unit circular arc area. Thus, the sound pressure distribution of the acoustic signal AC2 emitted from the sound hole 123a is point-symmetrical or substantially point-symmetrical with respect to the axis A1. Thus, the sound leakage component of the acoustic signal AC1 can be more appropriately offset by the acoustic signal AC2.

[0123] More preferably, the plurality of sound holes 123a are arranged along the circumference C1 in the same shape, the same size, and the same interval. For example, the plurality of sound holes 123a with a lateral width of 4 mm and a height of 3.5 mm are arranged along the circumference C1 in the same shape, the same size, and the same interval. When the plurality of sound holes 123a are arranged along the circumference C1 in the same shape, the same size, and the same interval, the sound leakage component of the sound signal AC1 can be more appropriately offset by the sound signal AC2. However, this does not limit the present invention.

[0124] In addition, it is preferable that the sound hole 123a (second sound hole) is provided in a wall portion ( 123b ) that is in contact with the region AR located on the other side (the D2 direction side) of the driver unit 11. Figure 3B ). Thus, the direct wave of the acoustic signal AC2 emitted from the other side of the driver unit 11 is efficiently led out from the sound hole 123a. As a result, the leakage sound component of the acoustic signal AC1 can be more appropriately offset by the acoustic signal AC2.

[0125] In the present embodiment, in order to simplify the description, the shape of the edge of the open end of the sound hole 123a is a quadrilateral (the open end is a square), but this does not limit the present invention. For example, the shape of the edge of the open end of the sound hole 123a can also be other shapes such as a circle, an ellipse, a triangle, etc. In addition, the open end of the sound hole 123a can also be a mesh shape. In other words, the open end of the sound hole 123a can also be composed of a plurality of holes. In addition, the number of the sound holes 123a is also not limited, and a single sound hole 123a can be provided in the area AR3 of the wall portion 123 of the shell 12, or a plurality of sound holes 123a can be provided.

[0126] The ratio S2 / S1 of the total opening area S2 of the sound holes 123a (second sound holes) to the total opening area S1 of the sound holes 121a (first sound holes) preferably satisfies 2 / 3≤S2 / S1≤4 (details will be described later). Thus, the sound leakage component of the acoustic signal AC1 can be appropriately offset by the acoustic signal AC2.

[0127] The sound leakage suppression performance sometimes also depends on the ratio of the area of ​​the wall portion 123 provided with the sound hole 123a to the opening area of ​​the sound hole 123a. For example, the following situation is assumed: the housing 12 has a wall portion 121, i.e., a first end face, which is arranged on one side (D1 direction side) of the drive unit 11; a wall portion 122, i.e., a second end face, which is arranged on the other side (D2 direction side) of the drive unit 11; and a wall portion 123, i.e., a side face, which surrounds a space sandwiched by the first end face and the second end face with the axis A1 along the emission direction (D1 direction) of the acoustic signal AC1 passing through the first end face and the second end face as the center, the sound hole 121a (first sound hole) is arranged on the first end face, and the sound hole 123a (second sound hole) is arranged on the side face ( Figure 2B , Figure 3B In this case, the ratio S2 / S3 of the total opening area S2 of the sound hole 123a to the total area S3 of the side surface is preferably 1 / 20≤S2 / S3≤1 / 5 (details will be described later). Thus, the sound leakage component of the sound signal AC1 can be appropriately offset by the sound signal AC2. However, this does not limit the present invention.

[0128] <Usage Status>

[0129] use Figure 5A , illustrating the usage state of the sound signal output device 10. Figure 5AIn the example, one sound signal output device 10 is worn on the right ear 1010 and the left ear 1020 of the user 1000. In order to wear the sound signal output device 10 on the ear, an arbitrary wearing mechanism is used. The D1 direction side of each sound signal output device 10 is respectively oriented to the user 1000 side. The output signal output from the playback device 100 is input to the driving unit 11 of each sound signal output device 10, and the driving unit 11 emits the sound signal AC1 to the D1 direction side and emits the sound signal AC2 to the other side. The sound signal AC1 is emitted from the sound hole 121a, and the emitted sound signal AC1 enters the right ear 1010 and the left ear 1020, and is heard by the user 1000. On the other hand, the sound signal AC2, which is an inverted signal of the sound signal AC1 or a signal similar to the inverted signal, is emitted from the sound hole 123a. A part of the sound signal AC2 cancels a part of the sound signal AC1 emitted from the sound hole 121a (leakage component).

[0130] <Experimental Results>

[0131] The experimental results showing the sound leakage suppression effect of the sound signal output device 10 according to the present embodiment are shown. Figure 5B As shown, the sound signal output device 10 is worn on both ears of a simulation head 1100 imitating a human head, and sound signals are observed at positions P1 and P2. Position P1 in this example is near the left ear 1120 of the simulation head 1100 (near the sound signal output device 10), and position P2 is a position 15 cm away from position P1.

[0132] Figure 6 Example in Figure 5B The frequency characteristics of the acoustic signal observed at position P1, Figure 7 Example in Figure 5B The frequency characteristics of the acoustic signal observed at position P2, Figure 8 The difference between the frequency characteristics of the sound signal observed at position P1 and the frequency characteristics of the sound signal observed at position P2 (the difference in sound pressure level at each frequency) is shown. The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the sound pressure level (SPL) [dB]). The solid line graph shows the frequency characteristics when the sound signal output device 10 of the present embodiment is used, and the dotted line graph shows the frequency characteristics when the existing sound signal output device (open-type headphones) is used. Figure 8As shown in the example, it can be seen that when the sound signal output device 10 of the present embodiment is used, the difference in sound pressure between the sound signal observed at the position P1 and the sound signal observed at the position P2 is larger than when the conventional sound signal output device is used. This means that in the sound signal output device 10 of the present embodiment, the sound leakage at the position P2 can be suppressed compared with the conventional sound signal output device.

[0133] Fig. 9A The relationship between the ratio S2 / S1 of the sum of the opening areas S2 of the example sound holes 123a (second sound holes) to the sum of the opening areas S1 of the example sound holes 121a (first sound holes), and the difference between the frequency characteristics of the sound signal observed at the position P1 and the frequency characteristics of the sound signal observed at the position P2. The horizontal axis shows the ratio S2 / S1, and the vertical axis shows the sound pressure level (SPL [dB]) representing the difference. r12h6 shows the result when the number of sound holes 121a is 6 and the number of sound holes 123a is 4, r12h12 shows the result when the number of sound holes 121a is 12 and the number of sound holes 123a is 4, and r45h35 shows the result when the number of sound holes 121a is 1 and the number of sound holes 123a is 4. As shown in FIG. Fig. 9A As shown in the example, it can be seen that the difference in sound pressure between the acoustic signal observed at the position P1 and the acoustic signal observed at the position P2 is large, especially in the range where the ratio S2 / S1 of the total opening area S2 of the sound holes 123a to the total opening area S1 of the sound holes 121a is 2 / 3≤S2 / S1≤4. This means that the sound leakage suppression effect is large in this range.

[0134] Fig. 9B The relationship between the ratio S2 / S3 of the total opening area S2 of the example sound hole 123a (second sound hole) to the total area S3 of the side surface and the difference between the frequency characteristics of the sound signal observed at position P1 and the frequency characteristics of the sound signal observed at position P2. The horizontal axis shows the ratio S2 / S3, and the vertical axis shows the sound pressure level (SPL) [dB] representing the difference. The meanings of r12h6, r12h12, and r45h35 are the same as Fig. 9A Same. Fig. 9B As shown in the example, it can be seen that, in particular, when the ratio S2 / S3 of the total opening area S2 of the sound hole 123a (second sound hole) to the total area S3 of the side surface is within the range of 1 / 20≤S2 / S3≤1 / 5, the difference in sound pressure between the acoustic signal observed at the position P1 and the acoustic signal observed at the position P2 is large. This indicates that the sound leakage suppression effect is large within this range.

[0135] [Modification 1 of the first embodiment]

[0136] In the first embodiment, an example is shown in which a plurality of sound holes 123a (second sound holes) of the same shape, size, and spacing are arranged along the circumference C1. However, this does not limit the present invention. Alternatively, a plurality of sound holes 123a of different shapes and / or sizes and / or spacings may be arranged along the circumference C1. For example, Fig. 10A , Fig. 10B , Fig.11A , Fig. 11B , Fig. 12A As shown in the example, a plurality of sound holes 123a with different shapes and intervals are provided on the wall portion 123 along the circumference C1. Fig. 12B As shown in the example, a plurality of sound holes 123a with different intervals are arranged on the wall portion 123 along the circumference C1, and it is also possible to Fig. 12C As illustrated in FIG. 1 , a plurality of sound holes 123 a having different shapes and sizes are provided on the wall portion 123 along the circumference C1 .

[0137] Furthermore, even in this case, when the circumference C1 is equally divided into a plurality of unit arc regions, it is preferable that the sum of the opening areas of the sound holes 123a (second sound holes) arranged along the first arc region as any one of the unit arc regions is the same or substantially the same as the sum of the opening areas of the sound holes 123a arranged along the second arc region as any one of the unit arc regions other than the first arc region. It is more preferable that the sum of the opening areas of the sound holes 123a arranged along the respective unit arc regions is the same or substantially the same for each unit arc region. For example, Fig. 10A , Fig. 10B , Fig.11A as well as Fig. 11B As shown in the example, the number and size of the sound holes 123a arranged in each unit arc area C1-1, C1-2, C1-3, and C1-4 are different from each other, but it is preferred that the sum of the opening areas of the sound holes 123a arranged in the unit arc area C1-1, the sum of the opening areas of the sound holes 123a arranged in the unit arc area C1-2, the sum of the opening areas of the sound holes 123a arranged in the unit arc area C1-3, and the sum of the opening areas of the sound holes 123a arranged in the unit arc area C1-4 are all the same or approximately the same.

[0138] The plurality of sound holes 123a only need to be arranged along the circumference C1, and all the sound holes 123a do not need to be strictly arranged on the circumference C1. Fig. 12A , Fig. 12B , Fig. 12CIn this way, all the sound holes 123a do not need to be arranged on the circumference C1, and the plurality of sound holes 123a may be arranged along the circumference C1. The position of the circumference C1 is not limited to the position exemplified in the first embodiment, and may be a circumference centered on the axis A1.

[0139] Furthermore, as long as a sufficient sound leakage suppression effect can be obtained, not all of the sound holes 123a need to be arranged along the circumference C1. That is, a part of the sound holes 123a may be arranged at a position deviated from the circumference C1. In addition, as long as a sufficient sound leakage suppression effect can be obtained, the number of the sound holes 123a is not limited, and one sound hole 123a may be provided.

[0140] [Variation 2 of the first embodiment]

[0141] In the first embodiment, a structure is illustrated in which one sound hole 121a is arranged at the central position (hereinafter referred to as "central position") of the area AR1 (the area of ​​the wall arranged on one side of the drive unit) of the wall 121 of the housing 12. However, a plurality of sound holes 121a may be arranged in the area AR1 of the wall 121 of the housing 12, and the sound hole 121a may be arranged at an eccentric position offset from the center (central position) of the area AR1 of the wall 121 of the housing 12. For example, Fig.13A As shown in the example, a sound hole 121a may be provided at an eccentric position (a position on an axis A12 parallel to the axis A1 and offset from the axis A1) (hereinafter referred to as an "eccentric position") on the area AR1. In other words, the position of the sound hole 121a provided in the area AR1 may be biased toward the eccentric position. Alternatively, Fig. 13B As shown in the example, a plurality of sound holes 121a may be provided in the area AR1, and these plurality of sound holes 121a may be offset to an eccentric position on an axis A12 which is offset from the axis A1 and parallel to the axis A1. In other words, the positions of the plurality of sound holes 121a provided in the area AR1 may also be offset to an eccentric position. That is, the sound hole 121a may be provided singly or in plurality, and the sound hole 121a may be offset to a central position of the area AR1 of the wall portion 121 of the shell 12, or to an eccentric position. In addition, the distance between the axis A1 and the axis A2 is not limited, and may be set according to the required sound leakage suppression performance. An example of the distance between the axis A1 and the axis A2 is 4 mm, but this does not limit the present invention.

[0142] The resonant frequency of the housing 12 can be controlled by the configuration structure of the sound holes 121a provided in the area AR1 (for example, the number, size, spacing, and configuration of the sound holes 121a). The resonant frequency of the housing 12 affects the frequency characteristics of the sound signals emitted from the sound holes 121a and 123a. Therefore, the frequency characteristics of the sound signals emitted from the sound holes 121a and 123a can be controlled by the configuration structure of the sound holes 121a provided in the area AR1. For example, if the frequencies of the sound signals AC1 and AC2 become higher, their wavelengths become shorter, and it is difficult to perform phase matching so that the leakage sound component of the sound signal AC1 emitted to the outside is offset by the sound signal AC2. As a result, the higher the frequencies of the sound signals AC1 and AC2, the more difficult it is to suppress the leakage sound of the sound signal AC1. Since the sound pressure levels of the sound signals AC1 and AC2 become larger at the resonant frequency of the housing 12, if the resonant frequency of the housing 12 belongs to the high frequency band where it is difficult to suppress the leakage sound, the leakage sound is perceived to be greater. In order to solve this problem, the arrangement structure of the sound holes 121 a may be set as in the following examples 2-1 and 2 to control the resonance frequency of the housing 12 .

[0143] <Example 2-1>

[0144] The arrangement structure of the sound hole 121a may be set so that the human auditory sensitivity to the resonance frequency of the housing 12 is reduced in the high frequency band where it is difficult to suppress sound leakage. For example, the position of the sound hole 121a to the housing 12 at a predetermined frequency f of a certain eccentric position may be set. th The auditory sensitivity (audibility) of the acoustic signal with the resonance frequency above is S d In addition, the sound hole 121a is set at the central position of the housing 12 at a predetermined frequency f th The auditory sensitivity of the acoustic signal with a resonant frequency above is S c Let the hearing sensitivity S in this case be d Specific hearing sensitivity S c That is, the predetermined frequency f of the housing 12 is low when the position of the sound hole 121a (first sound hole) is biased to a certain eccentric position (a position offset from the center of the area of ​​the wall portion arranged on one side of the driver unit). th The auditory sensitivity S of the acoustic signal with a resonance frequency above d The frequency f of the housing 12 is lower than the predetermined frequency f of the housing 12 when the sound hole 121a is assumed to be provided at the central position (the central portion of the region of the wall disposed on one side of the driver unit). th The auditory sensitivity S of the acoustic signal with a resonance frequency above cThe position of the sound hole 121a may be biased toward such an eccentric position. In addition, the auditory sensitivity may be any index as long as it is an index indicating the audibility of the sound. The higher the auditory sensitivity, the easier it is to hear. An example of auditory sensitivity is the inverse of the sound pressure level of the sound required for a person to perceive a sound of a standard size. For example, the inverse of the sound pressure level at each frequency in the equal loudness curve is the auditory sensitivity. The specified frequency f th This means the lower limit of the frequency band including the frequency at which it is difficult for the acoustic signal AC2 to cancel the leakage sound component of the acoustic signal AC1. th An example is 3000Hz, 4000Hz, 5000Hz, 6000Hz, etc.

[0145] <Example 2-2>

[0146] The arrangement structure of the sound hole 121a can also make the resonance peak of the magnitude of the sound signal AC1 and / or the sound signal AC2 emitted from the housing 12 smooth. For example, the magnitude of the sound signal AC1 emitted from the sound hole 121a of the housing 12 whose position is offset to a certain eccentric position and / or the magnitude of the sound signal AC2 emitted from the sound hole 123a is adjusted to a predetermined frequency f. th The sharpness of the peak above is Q d Furthermore, the magnitude of the acoustic signal AC1 emitted from the sound hole 121a of the housing 12 disposed at the center and / or the acoustic signal AC2 emitted from the sound hole 123a is adjusted to a predetermined frequency f. th The sharpness of the peak above is set as Q c . Let Q be the peak sharpness in this case. d Peak sharpness Q c That is, the magnitude of the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) of the housing 12 whose position is offset to a certain eccentric position and / or the acoustic signal AC2 (second acoustic signal) emitted from the sound hole 123a (second sound hole) is within the predetermined frequency f. th The sharpness of the peak above Q d The magnitude of the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) of the housing 12 and / or the acoustic signal AC2 (second acoustic signal) emitted from the sound hole 123a (second sound hole) is greater than the magnitude of the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) of the housing 12 when the sound hole 121a is assumed to be set at the center position at the predetermined frequency f. th The sharpness of the peak above Q c In other words, the magnitude of the acoustic signal AC1 and / or the acoustic signal AC2 emitted from the housing 12 whose sound hole 121a is offset to a certain eccentric position is within a predetermined frequency f. thThe above peak ratio is the magnitude of the acoustic signal AC1 and / or the acoustic signal AC2 emitted from the housing 12 assuming that the sound hole 121a is provided at the center position at the predetermined frequency f. th The position of the sound hole 121a may be shifted to such an eccentric position.

[0147] When the position of one or more sound holes 121a is biased toward the eccentric position, the distribution and opening area of ​​the sound holes 123a may also be shifted accordingly. Fig.13A or Fig. 13B In this way, the position of the single or multiple sound holes 121a provided in the area AR1 is biased toward an eccentric position on the axis A12 offset from the axis A1, as shown in FIG. Fig.14A as well as Fig. 14B As shown in the example, the opening area of ​​the sound hole 121a provided in the area AR3 is also biased toward the eccentric position side on the axis A12. Fig.14A In the example, the number of sound holes 123a arranged along the unit arc region C1-3 away from the eccentric position on the axis A12 is less than the number of sound holes 123a arranged along the unit arc region C1-1 closer to the eccentric position. Fig. 14B Examples are in Fig.14A In the example, each opening area of ​​the sound hole 123a provided along the unit arc region C1-3 away from the eccentric position on the axis A12 is smaller than each opening area of ​​the sound hole 123a provided along the unit arc region C1-1 closer to the eccentric position. That is, in the case where the circumference C1 is equally divided into a plurality of unit arc regions, the sum of the opening areas of the sound holes 123a (second sound holes) provided along the first arc region (for example, C1-3) as any one of the unit arc regions is smaller than the sum of the opening areas of the sound holes 123a provided along the second arc region (for example, C1-1) as any one of the unit arc regions closer to the eccentric position than the first arc region. In the case where the position of the sound hole 121a is biased toward the eccentric position, the distribution of the acoustic signal AC1 emitted from the sound hole 121a to the outside is also biased toward the eccentric position. Here, by shifting the distribution and opening area of ​​the sound holes 123a to the eccentric position, the distribution of the acoustic signal AC2 emitted from the sound holes 123a to the outside can also be shifted to the eccentric position. Thus, the sound leakage component of the acoustic signal AC1 can be fully offset by the emitted acoustic signal AC2.

[0148] In order to control the resonance frequency of the housing 12 for other purposes, the sound hole 121a may be biased to an eccentric position offset from the center (central position) of the area AR1 of the wall 121 of the housing 12. In addition, the size of the opening of the sound holes 121a and 123, the thickness of the wall of the housing 12, and the volume inside the housing 12 affect the resonance frequency of the housing 12. Therefore, by controlling at least a part of them, the resonance frequency of the housing 12 can be increased or decreased. That is, the larger the size of the opening of the sound holes 121a and 123, the thinner the thickness of the wall of the housing 12, and the smaller the volume inside the housing 12, the higher the resonance frequency of the housing 12 can be. On the contrary, the smaller the size of the opening of the sound holes 121a and 123, the thicker the thickness of the wall of the housing 12, and the larger the volume inside the housing 12, the lower the resonance frequency of the housing 12 can be.

[0149] [Variation 3 of the first embodiment]

[0150] As described above, in the first embodiment and its modified examples 1 and 2, the acoustic signal AC2 which is the inverted phase signal or the approximate signal of the inverted phase signal of the acoustic signal AC1 is emitted from the sound hole 123a, and a part of the acoustic signal AC1 emitted from the sound hole 121a (the leakage sound component) is canceled by a part of the emitted acoustic signal AC2. For this purpose, in the case where the direct wave of the acoustic signal AC1 is mainly emitted from the sound hole 121a, it is preferable to mainly emit the direct wave of the acoustic signal AC2 from the sound hole 123a. This is because the propagation path of the reflected wave is different from the propagation path of the direct wave. Therefore, in the case where the acoustic signal AC2 emitted from the sound hole 123a includes the reflected wave, the acoustic signal AC2 emitted from the sound hole 123a may have a different phase from the inverted phase signal or the approximate signal of the inverted phase signal of the acoustic signal AC1 emitted from the sound hole 121a, and there is a concern that the efficiency of canceling the leakage sound component is reduced. That is, it is preferable that the housing 12 has an internal structure that suppresses the echo of the acoustic signal AC2 (second acoustic signal) inside the housing 12 and mainly emits the direct wave of the acoustic signal AC2 from the sound hole 123a (second sound hole). Such a structure is exemplified below.

[0151] <Example 3-1>

[0152] An echo suppressing material (e.g., sponge or paper) for suppressing echoes may be provided in the inner region (e.g., region AR2, AR3) of the wall of the housing 12. The wall of the housing 12 itself may be formed of the echo suppressing material, or a sheet of echo suppressing material may be fixed to the wall of the housing 12. Alternatively, the inner region (e.g., region AR2, AR3) of the wall of the housing 12 may be shaped in a concave-convex shape to suppress echoes. Alternatively, a sheet having a concave-convex surface shape having an echo suppressing effect may be fixed to the inner region of the wall of the housing 12.

[0153] <Example 3-2>

[0154] like Fig.15A as well as Fig. 15B As shown in the example, the structure can also be as follows: the opening end of the sound hole 123a (second sound hole) is toward the edge 112a of the other side 112 (D2 direction side) of the driver unit 11, and the direct wave of the sound signal AC2 (second sound signal) released from the other side 112 of the driver unit 11 is mainly released from the sound hole 123a.

[0155] <Example 3-3>

[0156] like Fig. 15B As shown in the example, the following structure may be adopted: the wall portion 122 (region AR2) arranged on the other side of the driver unit 11 is not in contact with the driver unit 11 (not in contact during the driving of the driver unit 11), and the distance dis1 between the driver unit 11 and the wall portion 122 arranged on the other side 112 of the driver unit 1 is less than 5 mm, and the direct wave of the sound signal AC2 (second sound signal) is mainly emitted from the sound hole 123a (second sound hole). In addition, the region AR2 is not in contact with the driver unit 11 during the driving of the driver unit 11, which means, for example, that the distance dis1 is larger than the amplitude of the other side 112 of the driver unit 11 during the driving.

[0157] [Variation 4 of the first embodiment]

[0158] As mentioned above, the higher the frequencies of the acoustic signals AC1 and AC2, the shorter their wavelengths become, and it is difficult to offset the leakage sound component of the acoustic signal AC1 through the acoustic signal AC2. Depending on the situation, it is also conceivable that it is difficult to perform phase matching of the acoustic signals AC1 and AC2 at high frequencies, and the leakage sound component of the acoustic signal AC1 is amplified by the acoustic signal AC2 instead. Therefore, it is sometimes better to suppress the emission of the high-frequency acoustic signal AC2 from the sound hole 123a. Therefore, a sound-absorbing material that absorbs high-frequency acoustic signals may also be provided in the housing 12. The sound-absorbing material has a characteristic that the sound absorption rate of the acoustic signal with a frequency f1 is greater than the sound absorption rate of the acoustic signal with a frequency f2. Among them, the frequency f1 is higher than the frequency f2 (f1>f2). That is, the sound-absorbing material suppresses the high-frequency components of the acoustic signal more than the low-frequency components. The frequency f1 is a predetermined frequency f2 th Below, the frequency f2 is greater than the specified frequency f2 th . Specified frequency f2 th Examples are 3000 Hz, 4000 Hz, 5000 Hz, 6000 Hz, etc. In addition, when the energy of the sound signal input to the sound absorbing material is set to E in , the energy of the sound signal reflected by the sound absorbing material or the energy of the sound signal penetrating the sound absorbing material is set to Eout In the case of in -E out ) / E in Examples of such sound absorbing materials include paper such as Japanese paper and Japanese writing paper, nonwoven fabrics, silk, cotton, and the like.

[0159] <Example 4-1>

[0160] The sound absorbing material 13 may also be disposed in at least one of the sound holes 123a (second sound holes). Fig.16A As shown in the example, at least one of the sound holes 123a may be filled with the sound absorbing material 13. At least one of the inside and the outside of at least one of the sound holes 123a may be covered with the sound absorbing material 13.

[0161] <Example 4-2>

[0162] The sound absorbing material 13 may also be disposed in the area on the other side 112 (the D2 direction side) of the driving unit 11 inside the housing 12. Fig. 16B As shown in FIG. 1 , the sound absorbing material 13 may be fixed to the region AR2 of the wall portion 122 disposed on the other side 112 (the side in the direction D2 ) of the drive unit 11 . The sound absorbing material 13 may be fixed inside the wall portion 123 .

[0163] <Example 4-3>

[0164] Alternatively, the sound absorbing material 13 may be disposed in at least one of the sound holes 123a (second sound holes), and the sound absorbing material 13 may be disposed in the area on the other side 112 (the D2 direction side) of the driving unit 11 inside the housing 12. Fig. 16C As illustrated in FIG. 1 , the sound absorbing material 13 may be filled in at least one of the sound holes 123 a , and the sound absorbing material 13 may be fixed to the region AR2 of the wall portion 122 .

[0165] <Experimental Results>

[0166] The experimental results showing the sound leakage suppression effect of the acoustic signal output device 10 of this modification are shown. In this experiment, the acoustic signal output device 10 of the first embodiment was used (no acoustic absorbent) and the acoustic signal output device 10 in which the sound hole 123a was covered with an acoustic absorbent as shown in this modification (with acoustic absorbent). Japanese paper was used as the acoustic absorbent. In this experiment, Figure 5BAs shown, the sound signal output device 10 is worn on both ears of a simulation head 1100 imitating a human head, and sound signals are observed at positions P1 and P2. Position P1 is a position near the left ear 1120 of the simulation head 1100 (near the sound signal output device 10), and position P2 is a position 15 cm away from position P1.

[0167] Fig.17 Example in Figure 5B The frequency characteristics of the acoustic signal observed at position P1, Fig.18 Example in Figure 5B The frequency characteristics of the acoustic signal observed at position P2, Fig.19 The difference between the frequency characteristics of the acoustic signal observed at position P1 and the frequency characteristics of the acoustic signal observed at position P2 is illustrated. The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the sound pressure level (SPL) [dB]). The solid line graph illustrates the frequency characteristics when the acoustic signal output device 10 in which the sound hole 123a is covered with an acoustic absorbent material is used (with acoustic absorbent), and the dotted line graph illustrates the frequency characteristics when the acoustic signal output device 10 of the first embodiment is used (without acoustic absorbent). Fig.19 As shown in the example, it can be seen that in the frequency band of 2000 Hz or more, the difference in sound pressure between the acoustic signal observed at the position P1 and the acoustic signal observed at the position P2 is greater when the acoustic signal output device 10 in which the sound hole 123a is covered with the sound absorbing material is used than when the acoustic signal output device 10 without the sound absorbing material is used. This means that in the frequency band of 2000 Hz or more, the sound leakage at the position P2 can be suppressed more when the acoustic signal output device 10 in which the sound hole 123a is covered with the sound absorbing material is used.

[0168] [Variation 5 of the first embodiment]

[0169] Fig. 20A For example, a case where a sine wave acoustic signal AC1 is emitted from the sound hole 121a (first sound hole), and an acoustic signal AC2 (second acoustic signal) which is an inverted signal (phase inversion signal) of the acoustic signal AC1 is emitted from the sound hole 123a (second sound hole). Fig. 20A The horizontal axis shows the phase (Phase [degree]), and the vertical axis shows the magnitude (for example, amplitude, power) of the acoustic signals AC1 and AC2. The sound hole 121a and the sound hole 123a are separated by a distance D pn . D pnAs described above, part of the acoustic signal AC1 emitted from the sound hole 121a is offset by part of the acoustic signal AC2 emitted from the sound hole 123a, thereby suppressing the leakage of the acoustic signal AC1. However, the acoustic signals AC1 and AC2 have a distance D based on the distance D. pn The phase difference. Fig. 20B Show distance D pn The relationship between the phase difference and the frequency when the phase difference is 1.5 cm. Here, Fig. 20B The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the phase difference (Phase difference [degree]). Fig. 20B As shown in FIG. 1 , the higher the frequency, the further the phase difference is from 180°. Due to the influence of this phase difference, the acoustic signal AC1 emitted from the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a will not be completely in opposite phase. In particular, the acoustic signals AC1 and AC2 that satisfy D pn =(λ / 2)+nλ, the phases of the components of wavelength λ are consistent with each other, so the leakage sound is emphasized. Where n is a positive integer. That is, the closer it is to satisfy D pn =(λ / 2)+nλ, the larger the wavelength of the acoustic signal component λ, the more difficult it is to suppress sound leakage. Fig. 20C Example at distance D pn When the distance is 1.5 cm, the relationship between the maximum value of the sum of the magnitudes of the acoustic signal AC1 and the acoustic signal AC2 observed at a position 15 cm away from the acoustic signal output device and the frequencies of the acoustic signals AC1 and AC2. Fig. 20C The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the ratio of the maximum value of the sum of the magnitudes of the acoustic signal AC1 and the acoustic signal AC2 to the acoustic signal AC1. Fig. 20C In the example of , it can be seen that due to the above influence, from about 3000 Hz onwards, the ratio of the maximum value of the sum of the magnitudes of the acoustic signal AC1 and the acoustic signal AC2 to the acoustic signal AC1 exceeds 1, and sound leakage cannot be fully suppressed. pn , then it can make Fig. 20C However, due to mechanical constraints such as the configuration and shape of the sound holes 121a and 123a, the adjustable distance D pn There is also a limit, and it is not always possible to fully suppress sound leakage in the desired frequency band.

[0170] Therefore, the problem is solved by controlling the resonant frequency based on Helmholtz resonance. Fig.21AAs shown in the example, the sound signal output device 10 can be modeled as a Helmholtz resonator (enclosure), in which the length of the depth direction of the sound hole 121a (first sound hole) and the sound hole 123a (second sound hole) (duct length, for example, the depth of the sound holes 121a and 123a) is set to L [mm], and the sum of the opening areas of the sound hole 121a (first sound hole) and the sound hole 123a (second sound hole) is set to S [mm 2 ], the volume (capacity) of the internal space of the housing 12 (for example, the area AR) is set to V [mm 3 ] Based on the resonance frequency f of the Helmholtz resonance of the housing 12 modeled in this way H [Hz] is as follows.

[0171] [Mathematical formula 1]

[0172]

[0173] Where c is the speed of sound, S = S1 + ... + S K , S k (k=1, ..., K) is the opening area of ​​each sound hole 121a, 123a, K is the total number of sound holes 121a, 123a. F is a function, and F(S) is the function value of the F function based on S. The F function depends on the shape of the sound holes 121a, 123a. For example, when the sound holes 121a, 123a are rectangular, F(S)=S 1 / 2 . Fig.21B Example resonance frequency f H The relationship between the magnitude of the acoustic signal AC2 (inverted phase signal) in the housing 12. Here, Fig.21B The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the magnitude of the acoustic signal AC2 emitted from the drive unit 11 to the internal space (area AR) of the housing 12. Fig.21B As shown in the example, the magnitude of the acoustic signal AC2 emitted from the driver unit 11 to the internal space of the housing 12 is within the resonance frequency f H Furthermore, the phase of the acoustic signal AC2 emitted from the driver unit 11 to the internal space of the housing 12 is at the resonance frequency f H A big change before and after. Fig. 21C The relationship between the phase and frequency of the acoustic signal AC2 emitted from the driver unit 11 to the internal space of the housing 12 is illustrated. Here, Fig. 21CThe horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the phase (Phase [degree]) of the sound signal AC2 emitted from the sound hole 123a to the outside relative to the phase of the sound signal AC2 emitted from the driver unit 11 to the internal space of the housing 12 (based on the sound signal AC2 at the time when it is emitted from the driver unit 11 to the internal space of the housing 12). Fig. 21C As shown in the example, the phase of the acoustic signal AC2 emitted from the driver unit 11 to the internal space of the housing 12 is at the resonance frequency f H The higher the frequency, the closer the phase is to the phase delay of 180°. By controlling the resonance frequency f based on the Helmholtz resonance of the shell 12 H [Hz], adjusts the phase of the acoustic signal AC2 emitted from the sound hole 123a to the outside, and suppresses sound leakage at a desired frequency.

[0174] That is, Fig.22A As shown in the example, the acoustic signal AC1 emitted to one side (the D1 direction side) of the driving unit 11 is emitted from the sound hole 121a to the outside of the acoustic signal output device 10, and a part of it reaches the position P2 on the other side (the D2 direction side) of the acoustic signal output device 10. In addition, the acoustic signal AC2 emitted to the other side (the D2 direction side) of the driving unit 11 is emitted from the sound hole 123a to the outside of the acoustic signal output device 10 with a phase delay in the above manner based on the Helmholtz resonance of the housing 12, and a part of it reaches the position P2. Here, based on the above-mentioned formula (1), the length L of the sound holes 121a and 123a in the depth direction, the sum S of the opening areas of the sound holes 121a and 123a, and the volume V of the internal space of the housing 12 are adjusted to appropriately adjust the resonance frequency f based on the Helmholtz resonance of the housing 12. H , thereby adjusting the phase of the acoustic signal AC2 emitted from the drive unit 11 to the internal space of the housing 12. Thus, at a desired frequency, the phase difference between the acoustic signal AC1 and the acoustic signal AC2 at the position P2 can be made close to 180°, and sound leakage can be fully suppressed. Fig. 22B The example adjusts the distance D pn The resonance frequency f of the Helmholtz resonance of the housing 12 of 1.5 cm is H The relationship between the phase difference and frequency of the acoustic signal AC1 and the acoustic signal AC2 at the position P2 in [Hz]. Here, Fig. 22B The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the phase difference (Phase difference [degree]). Fig. 22CThe relationship between the maximum value of the sum of the magnitudes of the acoustic signal AC1 and the acoustic signal AC2 observed at the position P2 and the frequencies of the acoustic signals AC1 and AC2 is illustrated. Fig. 22C The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the ratio of the maximum value of the sum of the magnitudes of the acoustic signal AC1 and the acoustic signal AC2 to the acoustic signal AC1. Fig. 22B As shown in the example, it can be seen that by adjusting the length L, the total opening area S, and the volume V, the resonance frequency f H becomes about 6000Hz, so Fig. 22C As shown in the example, the maximum value of the sum of the magnitudes of the acoustic signal AC1 and the acoustic signal AC2 relative to the acoustic signal AC1 can be made less than 1 in a wide frequency band, and sound leakage can be fully suppressed. Sound leakage should be suppressed for frequencies within the audible frequency band, so the length L, the sum of the opening areas S, and the volume V (the length L of the sound holes 121a and the sound holes 123a in the depth direction, the sum of the opening areas S of the sound holes 121a and the sound holes 123a, and the volume V of the internal space of the housing 12) are designed so that at least the resonance frequency f H A specified frequency band within the audible band.

[0175] Let's explain it in more detail. Fig.23A As shown in the example, it is assumed that the sound hole 121a and the sound hole 123a are separated by a distance D pn , suppressing the sound leakage environment at position P2. Let y be the magnitude of the observation signal at position P2, ω be the frequency of the acoustic signals AC1 and AC2, t be the time, A be a positive constant representing the maximum value of the magnitude of the acoustic signal, and φ init Assuming that the constant represents the initial phase of the acoustic signals AC1 and AC2, the distance D pn The phase difference of the sound signals AC1 and AC2 is set to φ Dpn . Assuming that except for the distance D pn In the absence of any other factors causing the delay of the acoustic signal AC2 relative to the acoustic signal AC1 , the following relationship holds.

[0176] y=Asin(ωt-φ init +φ Dpn )+Asin(ωt-π-φ init ) (2)

[0177] φ Dpn =-(D pn ω) / c (3)

[0178] Since the phase difference φ Dpn , the acoustic signal AC2 will not be the opposite phase of the acoustic signal AC1, according to the phase difference φDpn , sometimes the sound leakage at position P2 cannot be fully suppressed. Therefore, the phase difference φ Dpn Phase difference (phase delay) φ c is introduced into the acoustic signal AC2 emitted to the outside of the acoustic signal output device 10. c In this case, the following relationship holds.

[0179] y=Asin(ωt-φ init +φ Dpn )+Asin(ωt-π-φ init +φ c ) (4)

[0180] By introducing a close phase difference φ Dpn The phase difference φ c , the size of y in equation (4) can be reduced, and the sound leakage at position P2 can be suppressed. In this modified example, the resonance frequency f based on the Helmholtz resonance of the housing 12 is adjusted by optimizing the length L, the total opening area S, and the volume V. H , which will be close to the phase difference φ Dpn The phase difference φ c is introduced into the acoustic signal AC2 emitted to the outside of the acoustic signal output device 10. By introducing such a phase difference φ c (with φ c (withφ c )), with no phase difference φ c Case (without φ c (withoutφ c )) can make the phase difference between the acoustic signal AC1 and the acoustic signal AC2 at the position P2 close to 180° in the frequency band where sound leakage is to be suppressed. Fig. 23B ). As a result, it is possible to sufficiently suppress sound leakage in this frequency band.

[0181] This is explained by the transfer function model. Fig.24A As shown in the example, it is assumed that the sound hole 121a and the sound hole 123a are separated by a distance D pn , suppress the sound leakage environment at position P2. Set the frequency domain signal of the observation signal at position P2 to Y lis (ω) Let the transfer function from one side (D1 direction side) of the driver unit 11 to the inner area of ​​the sound hole 121a be H pos,in (ω), the transfer function from the sound hole 121a to the outer area of ​​the position P2 is H pos,out (ω) Let the transfer function from the other side (D2 direction side) of the driver unit 11 to the inner area of ​​the sound hole 123a be H neg,in(ω), the transfer function from the sound hole 123a to the outer area of ​​the position P2 is H neg,out (ω). In addition, let S be the frequency domain signal of the acoustic signal AC1 emitted from one side (the D1 direction side) of the driving unit 11. pos (ω) Let the frequency domain signal of the acoustic signal AC2 emitted from the other side (the D2 direction side) of the driving unit 11 be S neg (ω). In this case, the following relationship holds.

[0182] Y lis (ω)=H pos,out (ω)H pos,in (ω)S pos (ω)+H neg,out (ω)H neg,in (ω)S neg (ω) (5)

[0183] Here, the frequency domain signal of the sound signal emitted by the sound source inside the driving unit 11 is represented by S sou (ω), let the transfer function on one side (the D1 direction side) of the sound source inside the driver unit 11 be H pos,spk (ω), let the transfer function on the other side (D2 direction side) of the sound source inside the driver unit 11 be H neg,spk (ω). Therefore, the following holds.

[0184] S pos (ω)=H pos,spk (ω)S sou (ω) (6)

[0185] S neg (ω)=-H neg,spk (ω)S sou (ω) (7)

[0186] According to the above formulas (5), (6), and (7), in order to obtain |Y lis (ω)|=0, it is sufficient to design the length L, the total opening area S, and the volume V so that the transfer function H of the area from the other side (D2 direction side) of the driver unit 11 to the sound hole 123a is neg,in (ω) only needs to satisfy the following.

[0187] H neg,in (ω)=H pos,out (ω)H pos,in (ω)H pos,spk (ω) / H neg,out (ω)H neg,spk (ω) (8)

[0188] Here, it is assumed that at the frequency ω to suppress sound leakage, H pos,spk(ω)=H neg,spk (ω) is established, H pos,in (ω) can be approximated to 1, and equation (8) can be transformed as follows.

[0189] H neg,in (ω)=H pos,out (ω) / H neg,out (ω) (9)

[0190] Here, assuming a free sound field and that the echo of the housing 12 can be ignored, the transfer function H pos,out (ω), H neg,out The phase characteristic of (ω) is considered to be linear. That is, the transfer function H pos,out (ω), H neg,out (ω) is considered to depend only on the distance-based delay. In this case, Fig. 24B As shown in the example, H in formula (9) neg,in The phase characteristic of (ω) can also be considered to be linear with respect to the frequency ω. Therefore, ideally, in the frequency band where the sound leakage at the position P2 is to be suppressed, the length L, the total opening area S, and the volume V are appropriately designed so that the phase characteristic H neg,in (ω) satisfies the right side of equation (9) or is close to equation (9), and sound leakage can be fully suppressed in the frequency band. For example, by designing the length L, the total opening area S, and the volume V, any one of Examples 1 to 7 that satisfies the following conditions can fully suppress sound leakage in the frequency band.

[0191] <Example 1 of conditions>

[0192] For any frequency ω, H neg,in (ω) and H pos,out (ω) / H neg,out (ω) is consistent or approximate (Formula (9)). Here, the frequency ω belongs to a predetermined frequency band of the audible frequency band. The predetermined frequency band is, for example, a frequency band in which sound leakage at the position P2 is to be suppressed.

[0193] <Example 2 of conditions>

[0194] |Y lis (ω)|<|H pos,out (ω)H pos,in (ω)S pos (ω)|(10a)

[0195] and

[0196] |Y lis (ω)|<|H neg,out (ω)H neg,in (ω)S neg (ω)|(10b)

[0197] <Example 3 of conditions>

[0198] |Y lis (ω)|<|H pos,out (ω)H pos,in (ω)S pos (ω)|(10a)

[0199] or

[0200] |Y lis (ω)|<|H neg,out (ω)H neg,in (ω)S neg (ω)|(10b)

[0201] <Example 4 of conditions>

[0202] |Y lis (ω)|<|H pos,out (ω)S pos (ω)|(11a)

[0203] and

[0204] |Y lis (ω)|<|H neg,out (ω)H neg,in (ω)S neg (ω)|(10b)

[0205] <Example 5 of conditions>

[0206] |Y lis (ω)|<|H pos,out (ω)S pos (ω)|(11a)

[0207] or

[0208] |Y lis (ω)|<|H neg,out (ω)H neg,in (ω)S neg (ω)|(10b)

[0209] <Example 6 of conditions>

[0210] The following design condition 1 and / or design condition 2 are satisfied.

[0211] Design condition 1:

[0212] When the sound signal AC1 (first sound signal) is emitted from the sound hole 121a (first sound hole) and the sound signal AC2 (second sound signal) is emitted from the sound hole 123a (second sound hole), the sound pressure level of the sound signal AC1 (first sound signal) at the position P2 (second location) is lower than the sound pressure level of the sound signal AC1 (first sound signal) at the position P2 (second location) when the sound signal AC1 (first sound signal) is emitted from the sound hole 121a (first sound hole) but the sound signal AC2 (second sound signal) is not emitted from the sound hole 123a (second sound hole) (for example, equations (10a) (11a)).

[0213] Design condition 2:

[0214] When the sound signal AC1 (first sound signal) is emitted from the sound hole 121a (first sound hole) and the sound signal AC2 (second sound signal) is emitted from the sound hole 123a (second sound hole), the sound pressure level of the sound signal AC1 (first sound signal) at the position P2 (second location) becomes lower than the sound pressure level of the sound signal AC1 (first sound signal) at the position P2 (second location) when the sound signal AC1 (first sound signal) is not emitted from the sound hole 121a (first sound hole) but the sound signal AC2 (second sound signal) is emitted from the sound hole 123a (second sound hole) (for example, formula (10b)).

[0215] <Example 7 of conditions>

[0216] The resonance frequency of the Helmholtz resonance of the housing 12 belongs to a frequency band of 3000 Hz to 8000 Hz.

[0217] Hereinafter, the structure of the sound signal output device 10 is described in which at least one of the length L of the sound holes 121a and 123a in the depth direction, the total opening area S of the sound holes 121a and 123a, and the volume V of the internal space of the housing 12 is adjusted. However, these are merely examples and do not limit the present invention.

[0218] <Design Example 1>

[0219] Fig.25A A design example is shown in which a cylindrical passage 123aa for adjusting L is further provided in the sound hole 123a provided in the housing 12 of the acoustic signal output device 10. Fig.25A The channel 123aa extends from the sound hole 123a toward the inside, thereby adjusting the length L in the depth direction of the sound hole 123a.

[0220] <Design Example 2>

[0221] Fig.25BAnother design example is shown in which a cylindrical passage 123aa for adjusting L is further provided in the sound hole 123a provided in the housing 12 of the acoustic signal output device 10. Fig.25A The difference of the example is that the channel 123aa extends from the sound hole 123a to the inner direction and the outer direction of the housing 12. In this way, the length L of the depth direction of the sound hole 123a can also be adjusted.

[0222] <Design Example 3>

[0223] Fig.25C The following is a design example in which an additional member 124 is provided in the region AR inside the housing 12 of the acoustic signal output device 10. By adjusting the capacity of the additional member 124, the volume V of the internal space (region AR) of the housing 12 can be adjusted.

[0224] <Design Example 4>

[0225] Fig.26A A design example in which a cylindrical passage 121 aa for adjusting L is provided in a sound hole 121 a provided in the housing 12 of the acoustic signal output device 10 is shown. Fig.26A The channel 121aa extends from the sound hole 121a toward the inside, thereby adjusting the length L in the depth direction of the sound hole 121a.

[0226] <Design Example 5>

[0227] Fig.26B The design example is also a design example in which a cylindrical passage 121aa for adjusting L is provided in the sound hole 121a provided in the housing 12 of the sound signal output device 10. Fig.26A The difference of the example is that the sound hole 121a is set at a position offset from the center of the sound signal output device 10, the inner diameter of the channel 121aa expands in a tapered shape from the inner side of the housing 12 to the outer side, and the channel 121aa extends from the sound hole 121a to the inner direction and the outer direction of the housing 12. In this way, the length L of the depth direction of the sound hole 121a can also be adjusted.

[0228] <Design Example 6>

[0229] Fig.26C The example of design is shown in which not only the sound hole 121a but also the sound hole 123a is provided on the D1 side of the driver unit 11 of the acoustic signal output device 10. In this way, the arrangement of the sound hole 123a is changed, the distance between the sound holes 121a and 123a is adjusted, and the volume V of the internal space of the housing 12 is also adjusted.

[0230] <Design Example 7>

[0231] Fig.27AThe following design example is shown: the sound hole 121a is not arranged on the D1 direction side (the emission direction side of the acoustic signal AC1) of the driver unit 11, but is arranged on the D6 direction side orthogonal to the D1 direction, and the sound hole 123a is also arranged on the same D6 direction side. In this way, the distance between the sound hole 121a and the sound hole 123a is adjusted, and the volume V of the internal space of the housing 12 is also adjusted.

[0232] <Design Example 8>

[0233] Fig.27B is Fig.27A In addition to the structure of , the sound hole 123a is also arranged on the D2 direction side. Thereby, the distance between the sound hole 121a and the sound hole 123a can be further adjusted.

[0234] <Design Example 9>

[0235] Fig.27C is Fig.27B Based on the structure of , a design example is provided in which a cylindrical passage 121aa is further provided in the sound hole 123a provided on the D2 direction side. Thereby, the length L in the depth direction of the sound hole 123a provided on the D2 direction side can be further adjusted.

[0236] <Design Example 10>

[0237] Fig.28A The present invention shows a design example in which a cylindrical horn 121ab is provided at the opening of the sound hole 121a of the housing 12 to improve the directivity of the sound signal AC1 emitted from the sound hole 121a in the direction D1. The inner diameter of the horn 121ab expands in a conical shape from the inside to the outside of the housing 12. Fig.28B As shown in the example, for example, the outer side (D1 direction side) of the speaker 121ab is arranged toward the right ear 1010 of the user 1000. The speaker 121ab can suppress the sound signal AC1 from wrapping around to the position P2, and can also adjust the phase difference between the sound signal AC1 emitted from the sound hole 121a and the sound signal AC2 emitted from the sound hole 123a. Furthermore, the length L of the depth direction of the sound hole 121a can also be adjusted by the speaker 121ab.

[0238] <Design Example 11>

[0239] Fig.29A yes Fig.28AA modified example of the structure is a design example in which a sound hole 121aba is provided on the side of the speaker 121ab. Since the higher the frequency component, the higher the straightness, the high-frequency component in the sound signal AC1 is difficult to be released from the sound hole 121aba on the side of the speaker 121ab, and the low-frequency component is easy to be released from the sound hole 121aba. Thus, the phase difference between the sound signal AC1 and the sound signal AC2 at the position P2 can be adjusted according to the frequency.

[0240] <Design Example 12>

[0241] Fig.29B yes Fig.29A A modified example is a design example in which a sound absorbing material 13 for absorbing high-frequency sound signals is provided in the sound hole 121aba provided on the side of the speaker 121ab and the sound hole 123a provided in the housing 12. Thus, the ratio of the magnitudes of the sound signal AC1 and the sound signal AC2 at the position P2 can be adjusted according to the frequency.

[0242] <Design Example 13>

[0243] Fig. 30A Too Fig.28A In a modified example, not only the sound hole 121a but also the sound hole 123a is provided on the D1 direction side of the driving unit 11 of the sound signal output device 10, and in addition to providing the speaker 121ab on the outside of the sound hole 121a of the housing 12, a cylindrical speaker 123ab surrounding the outside of the speaker 121ab is provided. The inner diameter of the speaker 123ab expands in a cone shape from the inside of the housing 12 toward the outside, and the speaker 121ab is arranged on the inside of the speaker 123ab. The opening of the sound hole 123a is arranged in the area between the speaker 123ab and the speaker 121ab (the area outside the speaker 123ab and inside the speaker 121ab). The sound signal AC2 emitted to the outside from the sound hole 123a is emitted to the outside through the gap 123aba between the speaker 123ab and the speaker 121ab. The speakers 123ab and 121ab can suppress the acoustic signals AC1 and AC2 from circling around the position P2, and can adjust the phase difference between the acoustic signal AC1 emitted from the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a. Furthermore, the speakers 121ab and 123ab can also adjust the length L of the sound holes 121a and 123a in the depth direction.

[0244] <Design Example 14>

[0245] Fig. 30B yes Fig.27AIn a modified example, the sound hole 121a is not arranged on the D1 direction side (the emission direction side of the acoustic signal AC1) of the driver unit 11, but is arranged on the D6 direction side orthogonal to the D1 direction, and the sound hole 123a is also arranged on the same D6 direction side. Fig. 30B In the design example, a cylindrical speaker 121ab for improving the directivity of the acoustic signal AC1 emitted from the sound hole 121a in the direction D6 is provided at the opening of the sound hole 121a of the housing 12, and a cylindrical speaker 123ac for improving the directivity of the acoustic signal AC2 emitted from the sound hole 123a in the direction D6 is provided at the opening of the sound hole 123a of the housing 12. By means of these speakers 121ab and 123ac, it is possible to suppress the sound signals AC1 and AC2 from circling around the aforementioned position P2, and it is also possible to adjust the phase difference between the acoustic signal AC1 emitted from the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a. Furthermore, the length L of the sound holes 121a and 123a in the depth direction is also adjusted by the speakers 121ab and 123ac.

[0246] <Experimental Results>

[0247] FIG. 2 shows the experimental results showing the sound leakage suppression effect of the acoustic signal output device 10 of this modification. Figure 5B As shown, the sound signal output device 10 is worn on both ears of a simulation head 1100 imitating a human head, and the sound signal is observed at positions P1 and P2. Position P1 in this example is near the left ear 1120 of the simulation head 1100 (near the sound signal output device 10), and position P2 is 15 cm away from position P1.

[0248] First, the frequency characteristics based on the difference in the total opening area S of the sound hole 121 a and the sound hole 123 a are exemplified. Fig.31A Illustrated in Figure 5B The frequency characteristics of the acoustic signal observed at position P1, Fig.31B Illustrated in Figure 5B The frequency characteristics of the acoustic signal observed at position P2, Fig.31C The difference between the frequency characteristics of the acoustic signal observed at position P1 and the frequency characteristics of the acoustic signal observed at position P2 (the difference in sound pressure level at each frequency) is illustrated. The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the sound pressure level (SPL) [dB]). Here, the opening area of ​​the sound hole 121a is set to be fixed, and the acoustic signal output device 10 with five types of opening areas of the sound hole 123a is evaluated. Any acoustic signal output device 10 has one sound hole 121a and four sound holes 123a. In addition, "standard" means that the total opening area of ​​the four sound holes 123a is 56mm 2In the sound signal output device 10, "0.5 times", "0.75 times", "1.25 times" and "1.5 times" respectively indicate that the total opening area of ​​the four sound holes 123a is 56 mm 2 The acoustic signal output device 10 is 0.5 times, 0.75 times, 1.25 times, and 1.5 times of S. Assume F(S) = S 1 / 2 The resonance frequencies f of the housing 12 of the acoustic signal output device 10 at "0.5 times", "0.75 times", "standard", "1.25 times", and "1.5 times" obtained according to formula (1) are: H [Hz] is as follows.

[0249] [Table 1]

[0250] condition <![CDATA[Resonant frequency f H [Hz]]]> 0.5 times 4260 0.75 times 4829 standard 5266 1.25 times 5626 1.5 times 5934

[0251] like Fig.31A as well as Fig.31B As shown in the example, due to the difference in the total opening area S, the frequency characteristics of the acoustic signal observed at position P1 and the acoustic signal observed at position P2 are different. Fig.31C As shown in the example, the frequency characteristics of the difference between the sound pressure of the acoustic signal observed at position P1 and the sound signal observed at position P2 are different according to the difference in the total opening area S, and the sound leakage suppression performance at position P2 is also different. For example, in the acoustic signal output device 10 of "standard", "1.25 times", and "1.5 times", at each resonance frequency f H At slightly higher frequencies, the sound leakage is very small, which is consistent with Fig. 22C The relationships illustrated are consistent.

[0252] Next, frequency characteristics based on the difference in volume V of the region AR (internal space) of the casing 12 will be exemplified. Fig.32A Illustrated in Figure 5B The frequency characteristics of the acoustic signal observed at position P1, Fig.32B Illustrated in Figure 5B The frequency characteristics of the acoustic signal observed at position P2, Fig.32C The difference between the frequency characteristics of the sound signal observed at position P1 and the frequency characteristics of the sound signal observed at position P2 (the difference in sound pressure level at each frequency) is shown in the figure. The horizontal axis shows the frequency (Frequency [Hz]) and the vertical axis shows the sound pressure level (SPL) [dB]). Here, the volume V is evaluated based on Fig.25CThe three types of acoustic signal output devices 10 shown in the example have different heights of the additional component 124. In addition, "standard" represents an acoustic signal output device 10 in which the height of the additional component 124 is a reference value, and "height + 1.0 mm" and "height + 2.0 mm" represent acoustic signal output devices 10 in which the height of the additional component 124 is 1.0 mm and 2.0 mm higher than "standard", respectively. Assume that F(S) = S 1 / 2 The resonance frequencies f of the housing 12 of the acoustic signal output device 10 at “standard”, “height + 1.0 mm”, and “height + 2.0 mm” obtained according to equation (1) are: H [Hz] are as follows.

[0253] [Table 2]

[0254] condition <![CDATA[Resonant frequency f H [Hz]]]> standard 5266 Height + 1.0 mm 4563 Height +2.0mm 4083

[0255] like Fig.32A as well as Fig.32B As shown in FIG. 1 , due to the difference in volume V of the internal space of the housing 12, the frequency characteristics of the acoustic signal observed at the position P1 and the acoustic signal observed at the position P2 are different. As a result, Fig.32C As shown in the example, the frequency characteristics of the difference between the sound pressure of the acoustic signal observed at position P1 and the sound signal observed at position P2 are different according to the difference in volume V of the internal space of the housing 12, and the sound leakage suppression performance at position P2 is also different. For example, in the acoustic signal output device 10 of "standard" and "height +1.0mm", at each resonance frequency f H At slightly higher frequencies, the sound leakage is very small, which is consistent with Fig. 22C The relationships illustrated are consistent.

[0256] Next, the frequency characteristics of the sound signal output device 10 of the embodiment (reference: having a housing as the area AR surrounded by the walls 122 and 123) and an open type (no housing) sound signal output device are illustrated. In addition, the open type sound signal output device does not have the wall 122 on the D1 direction side of the driving unit 11 of the sound signal output device 10, and the area AR is open to the D2 direction side. Fig.33A Illustrated in Figure 5B The frequency characteristics of the acoustic signal observed at position P1, Fig.33B Illustrated in Figure 5B The frequency characteristics of the acoustic signal observed at position P2, Fig.33C The difference between the frequency characteristics of the sound signal observed at position P1 and the frequency characteristics of the sound signal observed at position P2 (the difference in sound pressure level at each frequency) is shown. The horizontal axis shows the frequency (Frequency [Hz]), and the vertical axis shows the sound pressure level (SPL) [dB]). Fig.33A as well as Fig.33B As shown in the example, the frequency characteristics of the acoustic signal observed at position P1 and the acoustic signal observed at position P2 are different depending on whether there is a housing. Fig.33C As illustrated in FIG. 1 , it can be seen that the acoustic signal output device 10 according to the embodiment having a casing can suppress sound leakage at the position P2 in a wider frequency band than the acoustic signal output device not having a casing.

[0257] As described above, it can be seen that by appropriately adjusting the resonance frequency f of the Helmholtz resonance of the housing 12 H , it is possible to adjust the phase of the acoustic signal AC2 emitted from the driver unit 11 to the internal space of the housing 12, thereby being able to sufficiently suppress sound leakage in a desired frequency band.

[0258] [Variation 6 of the first embodiment]

[0259] In the fifth modification of the first embodiment, the phase relationship between the acoustic signal AC1 emitted from the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a is adjusted by controlling the resonance frequency based on the Helmholtz resonance. However, a waveguide (waveguide path of the acoustic signal) for adjusting at least one of the path length from the position of the drive unit 11 to the emission position of the acoustic signal AC1 (first acoustic signal) to the outside of the acoustic signal output device 10 and / or the path length from the position of the drive unit 11 to the emission position of the acoustic signal AC2 (second acoustic signal) to the outside of the acoustic signal output device 10 may be provided to adjust the phase relationship.

[0260] For example, the waveguide may be designed to satisfy any one of the above-mentioned conditions in Examples 1 to 6. Furthermore, when the phase relationship between the acoustic signal AC1 emitted from the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a is adjusted by the waveguide, the length L in the depth direction of the sound holes 121a and 123a, the total S of the opening areas of the sound holes 121a and 123a, and the volume V of the internal space of the housing 12 may be designed so as to reduce the influence of the resonance frequency based on the Helmholtz resonance of the housing 12. That is, when the phase relationship is adjusted by the waveguide, it may be difficult to adjust the phase in the frequency band where the sound leakage is to be suppressed due to the influence of the resonance frequency based on the Helmholtz resonance of the housing 12. In this case, the length L of the sound hole 121a and the sound hole 123a in the depth direction, the sum S of the opening areas of the sound hole 121a and the sound hole 123a, and the volume V of the internal space of the shell 12 may be designed so that the resonant frequency based on the Helmholtz resonance of the shell 12 is outside the specified frequency band within the audible band (for example, outside the band above 3000 Hz and below 8000 Hz. For example, a frequency band higher than 8000 Hz). Alternatively, the phase relationship between the acoustic signal AC1 emitted from the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a may be adjusted by both the waveguide and the resonant frequency based on the Helmholtz resonance of the shell 12. In this case, the length L of the sound hole 121a and the sound hole 123a in the depth direction, the sum S of the opening areas of the sound hole 121a and the sound hole 123a, and the volume V of the internal space of the shell 12 can also be designed so that the resonant frequency based on the Helmholtz resonance of the shell 12 belongs to a specified frequency band within the audible frequency band (for example, a band above 3000 Hz and below 8000 Hz).

[0261] Hereinafter, the structure of the acoustic signal output device 10 provided with the above-mentioned waveguide will be exemplified. However, these are examples and do not limit the present invention.

[0262] <Design Example 21>

[0263] Fig.34AThe design example of waveguides 125 and 126 for adjusting the path length from the position of the driving unit 11 to the release position of the acoustic signal AC2 (second acoustic signal) to the outside of the acoustic signal output device 10 is shown on the D2 direction side of the driving unit 11 in the housing 12 of the acoustic signal output device 10. The waveguides 125 and 126 are hollow paths (for example, sound tubes), one of which is arranged on the D2 direction side of the driving unit 11, and the other is arranged on the opening side of the sound hole 123a. The acoustic signal AC2 released to the D2 direction side of the driving unit 11 is released to the outside from the sound hole 123a via the waveguides 125 and 126. By adjusting the lengths of the waveguides 125 and 126, it is possible to adjust the phase difference at position P2 between the acoustic signal AC1 (first acoustic signal) emitted from the D1 direction side of the driver unit 11 and emitted from the sound hole 121a to the outside and the acoustic signal AC2 (second acoustic signal) emitted from the sound hole 123a to the outside via the waveguides 125 and 126. As a result, it is possible to sufficiently suppress sound leakage at a desired frequency at position P2.

[0264] <Design Example 22>

[0265] like Fig.34B In that case, a portion of the waveguide may also be arranged outside the housing 12. Fig.34B In the example, the front end portion 125 a of the waveguide 125 is arranged outside the housing 12 .

[0266] <Design Example 23>

[0267] Fig.34A The following design example is shown: a speaker 121ab functioning as a waveguide is provided on the D1 direction side of the driving unit 11 of the sound signal output device 10, and waveguides 125 and 126 for adjusting the path length from the position of the driving unit 11 to the release position of the sound signal AC2 (second sound signal) to the outside of the sound signal output device 10 are provided on the D2 direction side of the driving unit 11 in the housing 12 of the sound signal output device 10. Thus, both the path length from the position of the driving unit 11 to the release position of the sound signal AC1 (first sound signal) to the outside of the sound signal output device 10 and the path length from the position of the driving unit 11 to the release position of the sound signal AC2 (second sound signal) to the outside of the sound signal output device 10 can be adjusted.

[0268] In addition, the waveguide is not limited to a sound tube or a speaker, and may be any structure as long as it is a mechanical structure for adjusting at least one of the path length from the position of the drive unit 11 to the release position of the sound signal AC1 to the outside of the sound signal output device 11 and / or the path length from the position of the drive unit 11 to the release position of the sound signal AC2 to the outside of the sound signal output device 10.

[0269] [Variation 7 of the first embodiment]

[0270] In the fifth modification of the first embodiment, the phase relationship between the acoustic signal AC1 emitted from the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a is adjusted by controlling the resonance frequency based on the Helmholtz resonance. However, the phase relationship may be adjusted by arranging a vibrating body having a resonance frequency in a predetermined frequency band within the audible frequency band on the path of the acoustic signal AC2 emitted to the other side 112 (D2 direction side) of the drive unit 11, that is, on the path from the other side 112 (D2 direction side) of the acoustic signal output device 10 to the position P2 on the other side 112 (D2 direction side) of the acoustic signal output device 10, and setting it on the frame 12.

[0271] For example, the vibrator may be designed to satisfy any one of Examples 1 to 6 of the conditions described in Variation 5 of the first embodiment. Also, similar to Example 7 of the conditions described in Variation 5 of the first embodiment, the resonant frequency of the vibrator may be within a frequency band of 3000 Hz to 8000 Hz.

[0272] Hereinafter, the structure of the acoustic signal output device 10 provided with the above-mentioned vibrating body will be exemplified. However, these are merely examples and do not limit the present invention.

[0273] <Design Example 31>

[0274] exist Fig.35A The following is a design example in which a diaphragm 127 is provided as a vibrating body in the region AR inside the housing 12 of the sound signal output device 10. In this case, the diaphragm 127 is arranged between the other side 112 (D2 direction side) of the sound signal output device 10 and the sound hole 123a, which is the path of the sound signal AC2 to the other side 112 (D2 direction side) of the driver unit 11. The sound signal AC2 emitted to the D2 direction side of the driver unit 11 is emitted to the outside from the sound hole 123a via the above path. By providing the diaphragm 127 on this path, the phase difference at the position P2 between the sound signal AC1 (first sound signal) emitted from the D1 direction side of the driver unit 11 and emitted to the outside from the sound hole 121a and the sound signal AC2 (second sound signal) emitted to the outside from the sound hole 123a via the path where the diaphragm 127 is arranged can be adjusted. As a result, the sound leakage at the desired frequency can be sufficiently suppressed at the position P2.

[0275] <Design Example 32>

[0276] like Fig.35B As shown, the vibration membrane 127 can also be arranged in the sound hole 123a. Fig.35BIn the example, the diaphragm 127 is disposed in all the sound holes 123a.

[0277] <Design Example 33>

[0278] In addition, if Fig.35C As shown, the vibration membrane 127 may be disposed in a portion of the sound hole 123a.

[0279] <Design Example 34>

[0280] In addition, if Fig.36A As shown, the diaphragm 127 may also have air holes.

[0281] <Design Example 35>

[0282] In addition, if Fig.36B As shown, the frame 12 can also be configured in such a way that the wall 122, i.e., the second end face, on the other side 112 (D2 direction side) of the driver unit 11 is entirely formed into a sound hole 123a, and the second end face is replaced by a vibration membrane 127. In this case, the vibration membrane 127 maintains a certain dustproof and waterproof performance.

[0283] The vibration membrane 127 may be a film made of, for example, PET (polyethylene terephthalate). In addition, the vibrating body is not limited to the vibration membrane, and any vibrating body may be used as long as it receives a sound of a specified frequency and resonates. For example, a tuning fork may be used.

[0284] <Experimental Results>

[0285] The experimental results of the sound leakage suppression effect of the acoustic signal output device 10 of this modification are shown. Figure 5B When the sound signal output device 10 is installed on both ears of the dummy head 1100 simulating a human head, the sound signal is simulated at P2. More specifically, the simulation is performed by a circuit equivalent to the operation of three vibration membranes of different thicknesses (10 μm PET membrane, 20 μm PET membrane, 30 μm PET membrane).

[0286] First, the frequency characteristics of the leaked sound at the position P2 are exemplified. Fig.37A is a diagram illustrating the sound pressure level at position P2 of the acoustic signal AC1 at each frequency. Fig.37B is a diagram illustrating the sound pressure level at position P2 of the acoustic signal AC2 at each frequency. Fig.37CThe following are graphs showing the sound pressure level at position P2 of the acoustic signal after the acoustic signal AC1 at each frequency is cancelled out by the acoustic signal AC2. The horizontal axis represents the frequency (Frequency [Hz]) and the vertical axis represents the sound pressure level (SPL) [dB]). As can be seen from these graphs, the frequency characteristics of the sound leakage at position P2 change by changing the thickness of the diaphragm.

[0287] Next, the frequency characteristics of the leaked sound at the position P2 which also includes the low frequency band will be exemplified. Fig.38A The sound pressure level of the acoustic signal AC1 at each frequency is shown as an example. Fig.38B The sound pressure level of the acoustic signal AC2 at each frequency is shown as an example. Fig.38C The sound pressure level of the acoustic signal after the acoustic signal AC1 is offset by the acoustic signal AC2 at each frequency is shown. The horizontal axis represents the frequency (Frequency [Hz]), and the vertical axis represents the sound pressure level (SPL) [dB]). As can be seen from these figures, by changing the thickness of the diaphragm, the lowest resonance frequency of the diaphragm changes. The thinner the diaphragm, the lower the frequency band of the acoustic signal output.

[0288] Finally, the frequency characteristics regarding the phase at the position P2 are illustrated. Fig.39A The phase of the acoustic signal AC1 at each frequency is shown as an example. Fig.39B The phase of the acoustic signal AC2 at each frequency is illustrated. Fig.39C The phase of the acoustic signal after the acoustic signal AC1 is offset by the acoustic signal AC2 at each frequency is illustrated. The horizontal axis represents the frequency (Frequency [Hz]), and the vertical axis represents the phase (Phase [degree]). As can be seen from these figures, by changing the thickness of the vibrating membrane, the resonance frequency of the membrane changes, and the frequency of the phase inversion of the sound signal changes.

[0289] [Second embodiment]

[0290] Next, a second embodiment of the present invention will be described. The second embodiment is a modified example of the first embodiment. The following description will focus on the differences from the matters described so far, and the same reference numerals are used for matters already described to simplify the description.

[0291] In order to improve the sound quality of the sound signal output device 10 of the first embodiment or its modified examples, it is sometimes necessary to increase the size of the driving unit 11. However, in the first embodiment or its modified examples, if the size of the driving unit 11 becomes larger, the size and weight of the sound signal output device 10 itself also become larger. However, wearing a large-sized and heavy sound signal output device 10 near the external auditory canal will increase the burden on the ear and the foreign body sensation. Therefore, the shell with a sound hole and the driving unit 11 can also be set as separate bodies, and they can be connected by a waveguide. In this way, the size of the driving unit 11 can be increased without increasing the size and weight of the shell worn near the external auditory canal. The following is a detailed explanation.

[0292] The sound signal output device 20 of this embodiment is also a device for sound listening that is worn without sealing the external auditory canal of the user. Fig.40 As shown in the example, the sound signal output device 20 of the present embodiment includes: a drive unit 11; a shell 22 having hollow portions AR21, AR22 (first and second hollow portions); a shell 23 accommodating the drive unit 11 internally; hollow waveguides 24, 25 (first and second waveguides) connecting the shell 22 and the shell 23; and hollow joining members 26, 27 connecting the waveguides 24, 25 to the shell 22.

[0293] <Drive unit 11>

[0294] like Fig.40 As shown in the example, the drive unit 11 is a device that emits an acoustic signal AC1 (first acoustic signal) based on an input output signal to one side (D3 direction side), and emits an acoustic signal AC2 (second acoustic signal) that is an inverted signal of the acoustic signal AC1 or a signal similar to the inverted signal to the other side (D4 direction side). The structure of the drive unit 11 is the same as that of the first embodiment, except that the D1 direction is replaced by the D3 direction, and the D2 direction is replaced by the D4 direction.

[0295] <Casing 23>

[0296] like Fig.40As shown in the example, the housing 23 is a hollow member having a wall on the outside, and the drive unit 11 is accommodated inside. The shape of the housing 23 is not limited. For example, the shape of the housing 23 is preferably rotationally symmetrical (line symmetrical) or roughly rotationally symmetrical with the axis A2 extending in the D3 direction as the center. In the present embodiment, in order to simplify the description, an example is shown in which the housing 23 is roughly cylindrical with two end faces. However, this is an example and does not limit the present invention. For example, the housing 23 can be a roughly dome-shaped shape with a wall at the end, or a hollow roughly cubic shape, or other three-dimensional shapes. One end 241 of the waveguide 24 is installed on the wall 231 of the housing 23 on the side of the surface 111 of one side (D3 direction side) of the drive unit 11. In this way, the waveguide 24 (first waveguide) connected at one end 241 to the one side (D3 direction side) of the drive unit 11 will lead the sound signal AC1 emitted from the surface 111 of the drive unit 11 to one side (D3 direction side) to the outside of the housing 23. One end 251 of the waveguide 25 is mounted on the wall portion 232 of the housing 23 disposed on the side of the surface 112 on the other side (the D4 direction side) of the drive unit 11. In this way, the waveguide 25 (second waveguide) whose one end 251 is connected to the other side (the D4 direction side) of the drive unit 11, guides the acoustic signal AC2 emitted from the surface 112 of the drive unit 11 to the other side (the D4 direction side) to the outside of the housing 23. In addition, the material constituting the housing 23 is not limited. The housing 23 may be composed of a rigid body such as synthetic resin and metal, or may be composed of an elastic body such as rubber.

[0297] <Wave guide tubes 24, 25>

[0298] like Fig.40As shown in the example, the waveguides 24 and 25 are hollow members configured in a tubular shape, for example, and transmit the acoustic signals AC1 and AC2 input from one end 241 and 251 to the other end 242 and 252, respectively, and emit them from the other end 242 and 252. However, the waveguides 24 and 25 are not limited to being tubular, and may be any structure as long as they are structures that guide the acoustic signals collected at one end 241 and 251 (first position) to the other end 242 and 252 (second position) different from the one end 241 and 251 (first position). The length of the waveguides 24 and 25 is not limited, and it is preferred that the length of the acoustic channel of the waveguide 24 is equal to the length of the acoustic channel of the waveguide 25, or the difference between the length of the acoustic channel of the waveguide 24 and the length of the acoustic channel of the waveguide 25 is an integer multiple of the wavelength of the acoustic signals AC1 and AC2. That is, when the length of the sound channel of the waveguide 24 (first waveguide) is L1, the length of the sound channel of the waveguide 25 (second waveguide) is L2, and n is an integer, and the acoustic signal AC1 (first acoustic signal) and the acoustic signal AC2 (second acoustic signal) include an acoustic signal of wavelength λ, it is preferable to satisfy L1=L2+nλ. In addition, the sound channel refers to a passage of sound, and in the case of the waveguides 24 and 25 having the same inner diameter, a specific example of the length of the sound channel of the waveguides 24 and 25 is the length of the waveguides 24 and 25. In addition, the material constituting the waveguides 24 and 25 is not limited. The waveguides 24 and 25 may be composed of a rigid body such as synthetic resin and metal, or may be composed of an elastic body such as rubber.

[0299] <Joint member 26>

[0300] The joint member 26 is a hollow member having an open end 261 located on one side, a bottom surface, i.e., a wall portion 262, located on the other side of the open end 261, and a side surface, i.e., a wall portion 263, surrounding the space between the open end 261 and the wall portion 263 with the axis A1 as the center. The axis A1 of the present embodiment passes through the open end 261 and the wall portion 263. Preferably, the axis A1 is perpendicular or substantially perpendicular to the wall portion 262. In addition, preferably, the joint member 26 is rotationally symmetrical with respect to the axis A1. In the present embodiment, in order to simplify the description, an example in which the wall portion 263 is cylindrical is shown, but the wall portion 263 may also be other shapes such as a prism shape. The other end 242 of the waveguide 24 is mounted on the wall portion 263, and the acoustic signal AC1 emitted from the other end 242 of the waveguide 24 is introduced into the interior of the joint member 26 (the space between the open end 261 and the wall portion 263). The acoustic signal AC1 introduced into the interior of the joint member 26 is emitted from the open end 261. In addition, there is no limitation on the material constituting the joint member 26. The joint member 26 may be composed of a rigid body such as synthetic resin or metal, or may be composed of an elastic body such as rubber.

[0301] <Joint member 27>

[0302] Similarly, the joint member 27 is a hollow member having an open end 271 located on one side, a bottom surface located on the other side of the open end 271, namely a wall portion 272, and a side surface, namely a wall portion 273, which surrounds the space between the open end 271 and the wall portion 273 with the axis A1 as the center. The axis A1 of this embodiment passes through the open end 271 and the wall portion 273. Preferably, the axis A1 is perpendicular or substantially perpendicular to the wall portion 272. In addition, it is preferred that the joint member 27 is rotationally symmetrical with respect to the axis A1. In this embodiment, in order to simplify the description, an example in which the wall portion 273 is cylindrical is shown, but the wall portion 273 may also be other shapes such as a prism shape. The other end 252 of the waveguide 25 is installed on the wall portion 273, and the acoustic signal AC2 released from the other end 252 of the waveguide 25 is introduced into the interior of the joint member 27 (the space between the open end 271 and the wall portion 273). The acoustic signal AC2 introduced into the interior of the joint member 27 is released from the open end 271. The material constituting the joint member 27 is not limited. The joint member 27 may be composed of a rigid body such as synthetic resin or metal, or may be composed of an elastic body such as rubber.

[0303] <Casing 22>

[0304] like Fig.40 , Figure 41A-41C , Fig.42A as well as Fig.42B As shown in the example, the shell 22 of this embodiment has: a wall portion 221, which is located on one side (the D1 direction side); a wall portion 222, which is located on the other side (the D2 direction side); a wall portion 223, which surrounds the space between the wall portion 221 and the wall portion 222; and a wall portion 224, which separates the space surrounded by the wall portion 221, the wall portion 222 and the wall portion 223 into a hollow portion AR21 (a first hollow portion) and a hollow portion AR22 (a second hollow portion). In this embodiment, the hollow portion AR21 and the hollow portion AR22 are arranged on an axis A1 extending along the same D1 direction, for example, the central area of ​​the hollow portion AR21 and the central area of ​​the hollow portion AR22 are arranged on the same axis A1. Preferably, the internal space of the hollow portion AR21 is separated from the internal space of the hollow portion AR22 by the wall portion 224.

[0305] The joining member 26 to which the other end 242 of the waveguide 24 is mounted is fixed or integrated to the wall portion inside the hollow portion AR21, and the open end 261 side of the joining member 26 faces the wall portion 221 side. For example, the wall portion 262 side of the joining member 26 is fixed or integrated to the wall portion 224 inside the hollow portion AR21, and the open end 261 side faces the wall portion 221 side. In the example of this embodiment, the center of the wall portion 262 and the open end 261 of the joining member 26 is arranged on the axis A1. Thus, the other end 242 of the waveguide 24 is connected to the hollow portion AR21 via the joining member 26, and the acoustic signal AC1 transmitted to the joining member 26 is released from the open end 261 to the wall portion 221 side (D1 direction side). That is, for example, the joining member 26 is arranged on the axis A1, and the open end 261 of the joining member 26 opens in the direction D1 (first direction) along the axis A1, and the acoustic signal AC1 introduced from the other end 242 of the waveguide 24 is released in the direction D1 inside the hollow portion AR21.

[0306] A through hole 222a is provided in the wall portion 222 of the hollow portion AR22. The through hole 222a is preferably arranged on the axis A1, and more preferably, the center of the through hole 222a is arranged on the axis A1. In addition, the shape of the through hole 222a is not limited, and it is preferred that the open portion of the through hole 222a is rotationally symmetrical with respect to the axis A1, and it is more preferred that the edge of the open portion of the through hole 222a is a circle. The joining member 27 to which the other end 252 of the waveguide 25 is mounted is fixed or integrated with the outer side of the wall portion 222 of the shell 22, and the open end 271 side of the joining member 27 faces the through hole 222a. In the example of the present embodiment, the wall portion 272 of the joining member 27, the open end 271 and the center of the through hole 222a are arranged on the axis A1. Thus, the other end 252 of the waveguide 25 is connected to the hollow portion AR22 via the joint member 27, and the acoustic signal AC2 transmitted to the joint member 27 is released from the open end 271 to the internal space of the hollow portion AR22. For example, the acoustic signal AC2 is released from the open end 271 to the wall portion 224 side (the D1 direction side). That is, for example, the joint member 27 is arranged on the axis A1, and the open end 271 of the joint member 27 opens toward the direction D1 (first direction) along the axis A1, and the acoustic signal AC2 introduced from the other end 252 of the waveguide 25 is released toward the direction D1 inside the hollow portion AR22.

[0307] The shape of the shell 22 is not limited. For example, the shape of the shell 22 is preferably rotationally symmetrical or approximately rotationally symmetrical about the axis A1. In the present embodiment, in order to simplify the description, an example is shown in which the external shape of the shell 22 is a roughly cylindrical shape having walls 221 and 222 as two end faces and a wall 223 as a side. In addition, in the present embodiment, an example is shown in which the walls 221, 222, and 224 are perpendicular or approximately perpendicular to the axis A1, and the wall 223 is parallel or approximately parallel to the axis A1. However, these are examples and do not limit the present invention. For example, the external shape of the shell 22 can be a roughly dome-shaped shape with a wall at the end, a hollow roughly cubic shape, or other three-dimensional shapes. In addition, the material constituting the shell 22 is also not limited. The shell 22 can be composed of a rigid body such as a synthetic resin or metal, or an elastic body such as rubber.

[0308] <Sound holes 221a, 223a>

[0309] A sound hole 221a (first sound hole) is provided on the wall portion 221 of the hollow portion AR21 (first hollow portion) to guide the acoustic signal AC1 (first acoustic signal) introduced into the hollow portion AR21 through the waveguide 24 (first waveguide) to the outside. In addition, a sound hole 221a (second sound hole) is provided on the wall portion 223 of the hollow portion AR22 (second hollow portion) to guide the acoustic signal AC2 (second acoustic signal) introduced into the hollow portion AR22 through the waveguide 25 (second waveguide) to the outside. The sound holes 221a and 223a are, for example, through holes that penetrate the wall portion of the housing 12, similarly to the sound holes 121a and 123a of the first embodiment, but this does not limit the present invention. As long as the acoustic signal AC1 and the acoustic signal AC2 can be guided to the outside, respectively, the sound holes 221a and 223a may not be through holes.

[0310] The sound signal AC1 emitted from the sound hole 221a reaches the external auditory canal of the user and is heard by the user. On the other hand, the sound signal AC2 which is an inverted signal of the sound signal AC1 or a signal similar to the inverted signal is emitted from the sound hole 223a. A part of the sound signal AC2 cancels a part of the sound signal AC1 emitted from the sound hole 221a (the sound leakage component). Thus, the sound leakage can be suppressed.

[0311] The arrangement structure of the sound holes 221a and 223a is illustrated.

[0312] The sound hole 221a (first sound hole) of the present embodiment is provided in the wall portion 221 ( D1 direction side) of the hollow portion AR21 disposed on one side of the joint member 26 (the side where the acoustic signal AC1 is emitted). Fig.40 , Fig.41A , Fig.41B , Fig.42A ). In addition, the sound hole 223a (second sound hole) of this embodiment is provided in the wall portion 223 connected to the hollow portion AR22. That is, if the direction between the D1 direction (first direction) and the direction opposite to the D1 direction is set as the D12 direction (second direction) ( Fig.42A ), the sound hole 221a (first sound hole) is arranged on the D1 direction side (first direction side) of the shell 22, and the sound hole 223a (second sound hole) is arranged on the D12 direction side (second direction side) of the shell 22. That is, the sound hole 221a opens toward the D1 direction (first direction) along the axis A1, and the sound hole 223a opens toward the D12 direction (second direction). For example, when the outer shape of the shell 22 has: a wall portion 221, i.e., a first end face, arranged on one side (D1 direction side) of the joining member 26; a wall portion 222, i.e., a second end face, arranged on the other side (D2 direction side) of the joining member 26; and a wall portion 223, i.e., a side face, surrounding a space sandwiched by the first end face and the second end face with the axis A1 along the emission direction (D1 direction) of the acoustic signal AC1 passing through the first end face and the second end face as the center ( Fig.41B , Fig.42A ), the sound hole 221a (first sound hole) is provided on the first end surface, and the sound hole 223a (second sound hole) is provided on the side surface. In addition, in the present embodiment, no sound hole is provided on the wall portion 222 side of the housing 22. This is because if a sound hole is provided on the wall portion 222 side of the housing 22, the sound pressure level of the acoustic signal AC2 emitted from the housing 22 exceeds the level required to offset the sound leakage component of the acoustic signal AC1, and the excess is perceived as sound leakage.

[0313] like Fig.41AAs shown in the examples in the examples in the drawings, the sound hole 221a of the present embodiment is arranged on or near the axis A1 along the emission direction (D1 direction) of the acoustic signal AC1. The axis A1 of the present embodiment passes through the center of the area of ​​the wall portion 221 arranged on one side (D1 direction side) of the coupling member 26 or near the center. For example, the axis A1 is an axis that passes through the central area of ​​the shell 22 and extends in the D1 direction. That is, the sound hole 221a of the present embodiment is set at the central position of the area of ​​the wall portion 221 of the shell 22. In the present embodiment, in order to simplify the description, an example is shown in which the shape of the edge of the open end of the sound hole 221a is a circle (the open end is circular). However, this does not limit the present invention. For example, the shape of the edge of the open end of the sound hole 221a can also be other shapes such as an ellipse, a quadrilateral, a triangle, etc. In addition, the open end of the sound hole 221a can also be mesh-shaped. In other words, the open end of the sound hole 221a can also be composed of a plurality of holes. In addition, in this embodiment, for the sake of simplicity of description, an example is shown in which one sound hole 221 a is provided in the wall portion 221 of the housing 22. However, this does not limit the present invention. For example, two or more sound holes 221 a may be provided in the wall portion 221 of the housing 22.

[0314] As in the first embodiment, Fig.41B , Fig.42B As shown in the example, the sound holes 223a (second sound holes) of this embodiment are provided along a circumference C1 centered on the axis A1 along the emission direction of the acoustic signal AC1 (first acoustic signal). In this embodiment, for the sake of simplicity, an example is shown in which the plurality of sound holes 223a are provided on the circumference C1. However, the plurality of sound holes 223a only need to be provided along the circumference C1, and all the sound holes 223a do not need to be strictly arranged on the circumference C1.

[0315] In addition, similarly to the first embodiment, it is preferred that, when the circumference C1 is equally divided into a plurality of unit arc regions, the sum of the opening areas of the sound holes 223a (second sound holes) provided along a first arc region as any one of the unit arc regions is the same as or substantially the same as the sum of the opening areas of the sound holes 223a (second sound holes) provided along a second arc region as any one of the unit arc regions other than the first arc region. Fig.42B ).

[0316] As in the first embodiment, it is more preferable that the plurality of sound holes 223a are provided along the circumference C1 in the same shape, the same size, and the same intervals. However, this does not limit the present invention.

[0317] In the present embodiment, in order to simplify the description, the shape of the edge of the open end of the sound hole 223a is a quadrilateral, but this does not limit the present invention. For example, the shape of the edge of the open end of the sound hole 223a may also be other shapes such as a circle, an ellipse, a triangle, etc. In addition, the open end of the sound hole 223a may also be mesh-shaped. In other words, the open end of the sound hole 223a may also be composed of a plurality of holes. In addition, the number of the sound holes 223a is also not limited, and a single sound hole 223a may be provided on the wall portion 223 of the housing 22, or a plurality of sound holes 223a may be provided.

[0318] Similar to the first embodiment, the ratio S2 / S1 of the total opening area S2 of the sound holes 223a (second sound holes) to the total opening area S1 of the sound holes 221a (first sound holes) preferably satisfies 2 / 3≤S2 / S1≤4. In addition, when the outer shape of the housing 22 has: a wall portion 221, i.e., a first end face, arranged on one side (D1 direction side) of the coupling member 26; a wall portion 222, i.e., a second end face, arranged on the other side (D2 direction side) of the coupling member 26; and a wall portion 223, i.e., a side face, surrounding a space sandwiched by the first end face and the second end face with the axis A1 along the emission direction (D1 direction) of the acoustic signal AC1 passing through the first end face and the second end face as the center ( Fig.41B , Fig.42A ), the ratio S2 / S3 of the total opening area S2 of the sound hole 123a to the total area S3 of the side surface is preferably 1 / 20≤S2 / S3≤1 / 5.

[0319] <Usage Status>

[0320] use Fig.43A as well as Fig.43B , illustrating the usage state of the sound signal output device 20. Fig.43AIn the example of FIG. 1 , an acoustic signal output device 20 is worn on the right ear 1010 and the left ear (not shown) of the user 1000. In order to wear the acoustic signal output device 20 on the ears, an arbitrary wearing mechanism is used. The housing 22 of the acoustic signal output device 20 is arranged on the external auditory canal 1011 side of the right ear 1010 and the left ear, and the D1 direction side is respectively oriented to the external auditory canal 1011 side of the user 1000. In addition, the playback device 210 including the housing 23 is respectively arranged on the back side of the auricle of the right ear 1010 and the left ear, and as mentioned above, the housing 23 and the housing 22 are connected by the waveguide 24 and 25. The acoustic signal AC1 introduced from the driving unit 11 in the housing 23 into the hollow part AR21 of the housing 22 is released from the sound hole 221a, and the released acoustic signal AC1 is heard by the user 1000. On the other hand, the acoustic signal AC2 introduced from the driving unit 11 in the housing 23 into the hollow part AR22 of the housing 22 is released from the sound hole 123a. A part of the acoustic signal AC2 is an inverted phase signal of the acoustic signal AC1 or a signal approximating the inverted phase signal, and cancels a part of the acoustic signal AC1 (leakage sound component) emitted from the sound hole 221a.

[0321] like Fig.43B As in the example, the playback device 210 including the housing 23 is arranged on the head in front of the auricle of the right ear 1010 and the left ear. As mentioned above, the housing 23 and the housing 22 can also be connected by waveguides 24 and 25. Fig.43A Same as the example.

[0322] [Modification 1 of the Second Embodiment]

[0323] In the second embodiment, an example is shown in which a plurality of sound holes 223a (second sound holes) of the same shape, size, and spacing are arranged along the circumference C1. However, this does not limit the present invention. For example, the housing 22 may be provided with sound holes 223a (second sound holes) having the same arrangement structure as the sound holes 123a in the first modification of the first embodiment. FIG. 10A to FIG. 12C ).

[0324] [Variation 2 of the Second Embodiment]

[0325] In the second embodiment, a structure in which one sound hole 221a is arranged at the central position of the wall portion 221 of the housing 22 is illustrated. However, as in the second variation of the first embodiment, a plurality of sound holes 221a may be arranged in the region of the wall portion 221 of the housing 22, or the sound hole 221a may be arranged at an eccentric position offset from the center of the region of the wall portion 221 of the housing 22. For example, the housing 22 may be provided with sound holes 221a ( Fig.13A as well as Fig. 13B ).

[0326] In addition, similar to the second variation of the first embodiment, when the position of a single or multiple sound holes 221a is biased toward an eccentric position, the distribution and opening area of ​​the sound holes 223a may also be offset accordingly. That is, when the circumference C1 is equally divided into a plurality of unit arc regions, the sum of the opening areas of the sound holes 223a (second sound holes) arranged along a first arc region that is any one of the unit arc regions may also be smaller than the sum of the opening areas of the sound holes 123a arranged along a second arc region that is any one of the unit arc regions that is closer to the eccentric position than the first arc region. For example, a sound hole 223a (second sound hole) having the same configuration structure as that of the sound hole 123a in the second variation of the first embodiment may be provided in the housing 22. Fig.14A as well as Fig. 14B ). In addition, the resonance frequency of the housing 22 may be controlled by controlling the size of the openings of the sound holes 221a and 223, the thickness of the wall of the housing 22, and at least a portion of the volume inside the housing 22.

[0327] [Variation 3 of the Second Embodiment]

[0328] The acoustic signal output device 20 may be provided with a sound absorbing material having a higher sound absorption rate for an acoustic signal of frequency f1 than for an acoustic signal of frequency f2 (f1>f2) as described in the fourth modification of the first embodiment. The sound absorbing material may be provided on the other side 112 (the D4 direction side) of the driver unit 11 inside the housing 23, inside the waveguide 25 (the second waveguide), at the end (open end portion) of the waveguide 25, at least one of the sound holes 223a (the second sound hole), or inside the hollow portion AR22 (the second hollow portion). For example, the following structure may be adopted: in the examples 4-1 to 4-3 of the fourth modification of the first embodiment, the housing 12 is replaced by the hollow portion AR22, the sound hole 123a is replaced by the sound hole 223a, the area on the other side 112 of the driver unit 11 is replaced by the area inside the hollow portion AR22, and the area AR2 of the wall portion 122 is replaced by the area of ​​the wall portion 222.

[0329] [Variation 4 of the Second Embodiment]

[0330] By providing the coupling members 26 and 27 as in the second embodiment, it is possible to control the emission directions of the acoustic signals AC1 and AC2 in the hollow portions AR21 and AR22. For example, the acoustic signal AC1 introduced from the other end 242 of the waveguide 24 can be emitted from the inside of the hollow portion AR21 in the direction D1 along the axis A1, and the acoustic signal AC2 introduced from the other end 252 of the waveguide 25 can be emitted from the inside of the hollow portion AR22 in the direction D1. In this case, the sound pressure distributions of the acoustic signal AC1 emitted from the sound hole 221a and the acoustic signal AC2 emitted from the sound hole 223a can be set to be rotationally symmetrical or approximately rotationally symmetrical with respect to the axis A1. Thereby, sound leakage can be appropriately suppressed. However, this does not limit the present invention. For example, as Fig.44 , Fig.45A , Fig.45B , Fig.45C as well as Fig.46 As shown in the example, the acoustic signal output device 20 may not include the joint member 26, and the other end 242 of the waveguide 24 may be directly connected to the wall 223 of the hollow portion AR21, and the acoustic signal AC1 delivered to the other end 242 of the waveguide 24 may be released into the hollow portion AR21. Similarly, the acoustic signal output device 20 may not include the joint member 27, and the other end 252 of the waveguide 25 may be directly connected to the wall 223 of the hollow portion AR22, and the acoustic signal AC2 delivered to the other end 252 of the waveguide 25 may be released into the hollow portion AR22.

[0331] In the second embodiment, an example is shown in which the internal space of the hollow portion AR21 of the housing 22 is separated from the internal space of the hollow portion AR22 by the wall portion 224. Fig.40 , Fig.41B , Fig.42A ). However, the internal space of the hollow portion AR21 of the housing 22 may not be separated from the internal space of the hollow portion AR22. In this case, it is preferred that the open end 261 of the joint member 26 faces the wall portion 221 side (D1 direction side) of the housing 22 (for example, the sound hole 221a side), and the open end 271 of the joint member 27 faces the wall portion 222 side (D2 direction side) of the housing 22. Even with such a structure, the sound signal AC1 is released from the sound hole 221a, and the sound signal AC2 is released from the sound hole 223a.

[0332] [Third Embodiment]

[0333] It is also possible to provide a plurality of the sound signal output devices 10 described in the first embodiment or its modified example, and control them independently. Thus, the sound pressure level of the sound signal AC1 emitted from a certain sound signal output device 10 and the sound pressure level of the sound signal AC2 emitted from another sound signal output device 10 can be independently controlled. For example, it is also possible to drive a certain sound signal output device 10 and another sound signal output device 10 in reverse phase or substantially reverse phase, and independently control the level (power) at each frequency. Thus, as illustrated in the first embodiment, the leakage sound component of the sound signal AC1 of each sound signal output device 10 is canceled by a part of the sound signal AC2, and a part of the sound signal AC1 and a part of the sound signal AC2 respectively outputted from different sound signal output devices 10 can be canceled. As a result, the leakage sound component can be more appropriately canceled. In this embodiment, in order to simplify the description, an example is shown in which two sound signal output devices 10 are provided for one ear and they are independently controlled. However, this does not limit the present invention, and three or more sound signal output devices 10 may be provided for one ear and they may be independently controlled. In addition, for matters that have been described, the same reference numbers are used and the description is omitted, but the suffixes are used to distinguish between multiple components with the same structure. For example, two sound signal output devices 10 are described as sound signal output device 10-1 and sound signal output device 10-2, but the structures of sound signal output devices 10-1 and 2 are the same as those of sound signal output device 10.

[0334] The sound signal output device 30 of the present embodiment is a device for sound listening that is worn without sealing the external auditory canal of the user. Fig.47 as well as Fig.48 As illustrated in FIG. 1 , the sound signal output device 30 of the present embodiment includes the sound signal output devices 10 - 1 and 2 , a circuit unit 31 , and a connection unit 32 .

[0335] <Audio signal output device 10-1>

[0336] The structure of the sound signal output device 10-1 is the same as that of the sound signal output device 10 illustrated in the first embodiment and its modified example. That is, the sound signal output device 10-1 includes a driving unit 11-1 (first driving unit) and a housing 12-1 (first housing portion) that accommodates the driving unit 11-1. The driving unit 11-1 emits an acoustic signal AC1-1 (first acoustic signal) to the D1-1 direction side (one side) based on the input output signal I (electrical signal representing an acoustic signal), and emits an acoustic signal AC2-1 (second acoustic signal) that is an inverted signal of the acoustic signal AC1-1 (first acoustic signal) or an approximate signal of the inverted signal to the D2-1 direction side (the other side). A single or multiple sound holes 121a-1 (first sound holes) that guide the acoustic signal AC1-1 (first acoustic signal) emitted from the driving unit 11-1 to the outside are provided on the wall portion 121-1 of the housing 12-1. A single or multiple sound holes 123a-1 (second sound holes) for outputting the sound signal AC2-1 (second sound signal) emitted from the driving unit 11-1 to the outside are provided on the wall portion 123-1 of the housing 12-1. The details of the structure of the sound signal output device 10-1 are the same as those of the sound signal output device 10 described in the first embodiment. For example, the sound hole 123a-1 (second sound hole) is provided with multiple (first circumference) along a circle C1-1 (first circumference) centered on the axis A1-1 (first axis) which is parallel or substantially parallel to a straight line extending in the direction D1-1 (first direction). Fig.49 ). For example, in the case where the circumference C1-1 (first circumference) is equally divided into a plurality of first unit arc regions, the sum of the opening areas of the sound holes 123a-1 (second sound holes) arranged along the first arc region which is any one of the first unit arc regions is the same as or substantially the same as the sum of the opening areas of the sound holes 123a-1 (second sound holes) arranged along the second arc region which is any one of the first unit arc regions other than the first arc region.

[0337] <Audio signal output device 10-2>

[0338] The structure of the sound signal output device 10-2 is also the same as the sound signal output device 10 illustrated in the first embodiment and its modified example. That is, the sound signal output device 10-2 has a driving unit 11-2 (second driving unit) and a housing 12-2 (second housing portion) that accommodates the driving unit 11-2. Based on the input output signal II (electrical signal representing the sound signal), the driving unit 11-2 emits the sound signal AC1-2 (fourth sound signal) to the D1-2 direction side (one side), and emits the sound signal AC2-2 (third sound signal) which is an inverted signal of the sound signal AC1-2 or an approximate signal of the inverted signal to the D2-2 direction side (the other side). The phase of the sound signal AC1-2 (fourth sound signal) is the same as or similar to the phase of the sound signal AC2-1 (second sound signal). The phase of the sound signal AC2-2 (third sound signal) is the same as or similar to the phase of the sound signal AC1-1 (first sound signal). In addition, the drive unit 11-2 may be of the same design as the drive unit 11-1, or of a different design from the drive unit 11-1. For example, the drive unit 11-2 may be smaller than the drive unit 11-1, or the performance of the drive unit 11-2 may be inferior to that of the drive unit 11-1. A single or multiple sound holes 123a-2 (third sound holes) for exporting the sound signal AC2-2 (third sound signal) emitted from the drive unit 11-2 to the outside are provided on the wall portion 123-2 of the housing 12-2. A single or multiple sound holes 121a-2 (fourth sound holes) for exporting the sound signal AC1-2 (fourth sound signal) emitted from the drive unit 11-2 to the outside are provided on the wall portion 121-2 of the housing 12-2. The details of the structure of the sound signal output device 10-2 are the same as those of the sound signal output device 10 described in the first embodiment. For example, the sound hole 123a-2 (third sound hole) is provided with a plurality of ( Fig.49 ). For example, in the case where the circumference C1-2 (fourth circumference) is equally divided into a plurality of fourth unit arc regions, the sum of the opening areas of the sound holes 123a-2 (third sound holes) arranged along the third arc region which is any one of the fourth unit arc regions is the same as or substantially the same as the sum of the opening areas of the sound holes 123a-2 (third sound holes) arranged along the fourth arc region which is any one of the fourth unit arc regions other than the third arc region.

[0339] <Connection section 32>

[0340] like Fig.47 , Fig.48 as well as Fig.49As shown in the example in FIG. 1 , the connecting portion 32 fixes the housing 12 - 1 of the sound signal output device 10 - 1 and the housing 12 - 2 of the sound signal output device 10 - 2 to each other. Fig.48 In the example, the outer side of the wall portion 123-1 of the housing 12-1 of the sound signal output device 10-1 and the outer side of the wall portion 123-2 of the housing 12-2 of the sound signal output device 10-2 are joined. The sound hole 121a-1 (first sound hole) opens toward the direction D1-1 (first direction) along the axis A1-1. In addition, the direction D1-1 is the direction along the axis A1-1. The sound hole 123a-1 (second sound hole) opens toward the direction D12-1 (second direction) between the direction D1-1 (first direction) and the opposite direction of the direction D1-1 (first direction). The sound hole 121a-2 (fourth sound hole) opens toward the direction D1-2 (fourth direction) that is the same as or similar to the direction D1-1 (first direction). In addition, the direction D1-2 is the direction along the axis A1-2. The sound hole 123a-2 (third sound hole) opens toward D12-2 (third direction) between the direction D1-2 (fourth direction) and the direction opposite to the direction D1-2 (fourth direction). However, this arrangement is an example and does not limit the present invention.

[0341] like Fig.47 , Fig.48 as well as Fig.49 As shown in the example, it is preferred that the sound hole 121a-1 (first sound hole) and the sound hole 121a-2 (fourth sound hole) are plane-symmetrical or substantially plane-symmetrical with respect to the reference plane P31 including a straight line parallel or substantially parallel to the straight line (axis A1-1) extending in the direction D1-1 (first direction). Similarly, the sound hole 123a-1 (second sound hole) and the sound hole 123a-2 (third sound hole) are preferably plane-symmetrical or substantially plane-symmetrical with respect to the reference plane P31. It is more preferred that the housing 12-1 (first housing portion) and the housing 12-2 (second housing portion) are plane-symmetrical or substantially plane-symmetrical with respect to the reference plane P31.

[0342] <Circuit section 31>

[0343] The circuit unit 31 is a circuit that receives an input signal, which is an electrical signal representing an acoustic signal, as an input, and outputs an output signal I, which is an electrical signal for driving the drive unit 11-1, and an output signal II, which is an electrical signal for driving the drive unit 11-2. The output signal I and the output signal II are electrical signals representing the acoustic signal, and the output signal II is an inverted signal of the output signal I or a signal approximating the inverted signal. The following is an example of the structure of the circuit unit 31.

[0344] <Configuration Example 1 of Circuit Section 31>

[0345] Fig.50AThe circuit unit 31 illustrated in the figure has a phase inversion unit 311 as a phase inversion circuit. The input signal input to the circuit unit 31 is directly output as an output signal I and supplied to the driving unit 11-1. Furthermore, the input signal input to the circuit unit 31 is also input to the phase inversion unit 311. The phase inversion unit 311 outputs an inverted signal of the input signal or an approximate signal of the inverted signal as an output signal II. The output signal II is supplied to the driving unit 11-2.

[0346] <Configuration Example 2 of Circuit Section 31>

[0347] Fig.50BThe circuit unit 31 illustrated in the example has a level correction unit 312, a phase control unit 313 and a delay correction unit 314. The input signal input to the circuit unit 31 is input to the level correction unit 312 and the delay correction unit 314. The level correction unit 312 adjusts the level of each frequency band of the input signal and outputs the resulting band level adjustment completed signal. That is, if the designs (caliber, structure, etc.) of the drive units 11-1 and 2 are different from each other, the frequency characteristics of the sound signals output from the drive units 11-1 and 2 are also different. The difference in the frequency characteristics of the sound signals output from the drive units 11-1 and 2 is related to the cancellation effect of the leakage sound. For example, if the housing 12-1 and the housing 12-2 are plane-symmetrical with respect to the reference plane P31, in order to improve the cancellation effect of the leakage sound, it is preferred that the frequency characteristics of the sound signals output from the drive units 11-1 and 2 are the same. Therefore, it is preferred to adjust the output signal so that the frequency characteristics of the sound signals output from the drive units 11-1 and 2 are the same. On the other hand, when the housing 12-1 and the housing 12-2 are not plane-symmetrical with respect to the reference plane P31, it is preferable to adjust the balance of the frequency characteristics of the sound signals output from the driving units 11-1 and 2 according to these asymmetries so as to increase the effect of canceling the leakage sound. The level correction unit 312 achieves this by adjusting the level of each band of the input signal. The band level adjustment signal output from the level correction unit 312 is input to the phase control unit 313. The phase control unit 313 generates an inverted signal of the band level adjustment signal or an approximate signal of the inverted signal, and outputs it as an output signal II. The phase control unit 313 is, for example, a phase inversion circuit or an all-pass filter. When the phase control unit 313 is an all-pass filter, it is possible to generate an inverted signal of the band level adjustment signal or an approximate signal of the inverted signal in consideration of the phase characteristics of the level correction unit 312. The output signal II is supplied to the driving unit 11-2. In addition, the delay correction unit 314 outputs an output signal I in which the delay amount of the input signal input is adjusted. That is, when a delay is generated in the processing (filter processing) of the level correction unit 312 and the phase control unit 313, the delay correction unit 314 adjusts the delay amount. As a result, the phase of the sound signal output from the drive units 11-1 and 2 can be adjusted to improve the sound leakage suppression effect. The output signal I is supplied to the drive unit 11-1. As described above, in the configuration example 2 of the circuit unit 31, the output signal I and the output signal II based on the input signal can be independently controlled.

[0348] <Configuration Example 3 of Circuit Section 31>

[0349] As mentioned above, the higher the frequencies of the acoustic signals AC1 and AC2, the shorter their wavelengths become, and it is difficult to cancel out the sound leakage component of the acoustic signal AC1 through the acoustic signal AC2. For example, this cancellation becomes difficult in the frequency domain exceeding 6000Hz. Therefore, in such a high frequency band, the acoustic signal AC2 used to suppress the sound leakage component may actually contribute to the sound leakage. On the other hand, in headphones, etc., the level of the low-frequency sound range is weak, so the impact of the sound leakage is also small. For example, in the frequency domain below 2000Hz, the impact of the sound leakage is small. Therefore, in such a low frequency band, the importance of the acoustic signal AC2 used to suppress the sound leakage component is low. Furthermore, people have a relatively high auditory sensitivity to acoustic signals with frequencies of 2000Hz to 6000Hz. That is, the importance of the acoustic signal AC2 for suppressing the sound leakage component of the acoustic signal AC1 in such a frequency band is high.

[0350] From the above viewpoint, when the user listens to the sound signal AC1 emitted from the sound hole 121a-1 of the sound signal output device 10-1, the frequency band of the sound signal emitted from the sound signal output device 10-2 may be limited compared to the frequency band of the sound signal emitted from the sound signal output device 10-1. That is, the frequency bandwidth BW-2 of the sound signal AC2-2 and the sound signal AC1-2 (the third sound signal and the fourth sound signal) emitted from the drive unit 11-2 (the second drive unit) may be narrower than the frequency bandwidth BW-1 of the sound signals AC1-1 and AC2-1 (the first sound signal and the second sound signal) emitted from the drive unit 11-1 (the first drive unit).

[0351] Example 31-1:

[0352] For example, the magnitude of the high frequency side of the acoustic signal AC2-2 and the acoustic signal AC1-2 may be suppressed compared to the magnitude (level) of the high frequency side of the acoustic signal AC1-1 and the acoustic signal AC2-1. That is, the frequency f of the acoustic signal AC2-2 and AC1-2 (the third acoustic signal and the fourth acoustic signal) emitted from the driving unit 11-2 (the second driving unit) may be suppressed. 31 The magnitude of the component above (the first frequency) may be smaller than the frequency f of the acoustic signals AC1-1 and AC2-1 (the first acoustic signal and the second acoustic signal) emitted from the drive unit 11-1 (the first drive unit). 31 For example, the drive unit 11-2 may also output a suppressed frequency f 31 The above frequency bands are the acoustic signal AC2-2 and the acoustic signal AC1-2. 31 Specific examples are 3000Hz, 4000Hz, 5000Hz, 6000Hz, etc.

[0353] Example 31-2:

[0354] For example, the magnitude of the low-frequency side of the acoustic signal AC2-2 and the acoustic signal AC1-2 may be suppressed compared to the magnitude of the low-frequency side of the acoustic signal AC1-1 and the acoustic signal AC2-1. That is, the frequency f of the acoustic signal AC2-2 and AC1-2 (the third acoustic signal and the fourth acoustic signal) emitted from the driving unit 11-2 (the second driving unit) is 32 The magnitude of the component below (the second frequency) may be smaller than the frequency f of the acoustic signals AC1-1 and AC2-1 (the first acoustic signal and the second acoustic signal) emitted from the drive unit 11-1 (the first drive unit). 32 For example, the drive unit 11-2 may also output a suppressed frequency f 32 The following frequency bands are used to represent the acoustic signal AC2-2 and the acoustic signal AC1-2. 32 Specific examples are 1000 Hz, 2000 Hz, 3000 Hz, etc.

[0355] Example 31-3:

[0356] For example, the magnitude of the high frequency side of the acoustic signal AC2-2 and the acoustic signal AC1-2 may be suppressed compared to the magnitude of the high frequency side of the acoustic signal AC2-1 and the acoustic signal AC1-1, and the magnitude of the low frequency side of the acoustic signal AC2-2 and the acoustic signal AC1-2 may be suppressed compared to the magnitude of the low frequency side of the acoustic signal AC2-1 and the acoustic signal AC1-1. For example, the driving unit 11-2 may output the suppressed frequency f 32 The following frequency bands and frequencies f 31 The acoustic signal AC2-2 and the acoustic signal AC1-2 (for example, only the frequency f 32 With frequency f 31 The signal in the frequency band between the audio signal AC2-2 and the audio signal AC1-2).

[0357] Hereinafter, a third configuration example of the circuit unit 31 for realizing these will be described.

[0358] like Fig.50C As shown in the example, the circuit unit 31 of this example includes a level correction unit 312, a phase control unit 313, a delay correction unit 314, and a bandpass filter unit 315. The input signal input to the circuit unit 31 is input to the bandpass filter unit 315 and the delay correction unit 314. The bandpass filter unit 315 obtains a band-limited signal that limits (narrows) the band of the input signal and outputs it. In the case of the above-mentioned example 31-1, the high-frequency side of the input signal (for example, the frequency f 31In the case of the above example 31-2, the low-frequency side of the input signal (for example, the frequency f 32 In the case of the above-mentioned Example 31-3, the high-frequency side of the input signal (for example, the frequency f 31 The frequency band above) and the low frequency side (for example, the frequency f 32 A signal in the following frequency band) is output as a band-limited signal.

[0359] The band limited signal is input to the level correction unit 312. The level correction unit 312 adjusts the level of each band of the band limited signal and outputs the band level adjustment completed signal obtained thereby. The band level adjustment completed signal output from the level correction unit 312 is input to the phase control unit 313. The phase control unit 313 generates an inverted signal of the band level adjustment completed signal or an approximate signal of the inverted signal and outputs it as an output signal II. The output signal II is supplied to the driving unit 11-2. In addition, the delay correction unit 314 outputs an output signal I in which the delay amount of the input signal is adjusted.

[0360] <Usage Status>

[0361] use Fig.51 , illustrating the usage state of the sound signal output device 30. Fig.51The user 1000 wears one sound signal output device 30 on the right ear 1010 and the left ear (not shown). The D1 direction side of each sound signal output device 10-1 of the sound signal output device 30 faces the external auditory canal 1011 side of the user 1000. In addition, the sound signal output device 10-2 is arranged at a position offset from the external auditory canal 1011. For example, when the sound signal output device 30 is worn on the ear, the sound hole 121a-1 (first sound hole) is arranged in the direction of the external auditory canal 1022, and the sound hole 123a-1 (second sound hole), the sound hole 123a-2 (third sound hole) and the sound hole 121a-2 (fourth sound hole) are arranged in the direction other than the external auditory canal 1022. Any wearing mechanism is used to wear the sound signal output device 30 on the ear. The sound signal AC1-1 (first sound signal) emitted from the sound hole 121a-1 (first sound hole) of the sound signal output device 10-1 is heard by the user 1000. On the other hand, part of the acoustic signal AC2-1 (second acoustic signal) emitted from the sound hole 123a-1 (second sound hole) cancels part of the acoustic signal AC1-1 (first acoustic signal) emitted from the sound hole 121a-1 (first sound hole). In addition, part of the acoustic signal AC2-2 (third acoustic signal) emitted from the sound hole 123a-2 (third sound hole) cancels part of the acoustic signal AC1-2 (fourth acoustic signal) emitted from the sound hole 121a-2 (fourth sound hole). In addition, part of the acoustic signal AC2-2 (third acoustic signal) emitted from the sound hole 123a-2 (third sound hole) cancels part of the acoustic signal AC2-1 (second acoustic signal) emitted from the sound hole 123a-1 (second sound hole). In addition, part of the acoustic signal AC1-2 (fourth acoustic signal) emitted from the sound hole 121a-2 (fourth sound hole) cancels part of the acoustic signal AC1-1 (first acoustic signal) emitted from the sound hole 121a-1 (first sound hole). That is, in this embodiment, the sound signal AC1-1 (first sound signal) is emitted from the sound hole 121a-1 (first sound hole), the sound signal AC2-1 (second sound signal) is emitted from the sound hole 123a-1 (second sound hole), the sound signal AC2-2 (third sound signal) is emitted from the sound hole 123a-2 (third sound hole), and the sound signal AC1-2 (fourth sound signal) is emitted from the sound hole 121a-2 (fourth sound hole). In this case, the attenuation rate η of the sound signal AC1-1 (first sound signal) at the position P2 (second point) with respect to the position P1 (first point) is 11 The attenuation rate η of the acoustic signal due to air propagation at position P2 (second position) based on position P1 (first position) is smaller than that at position P2 (second position). 21 The predetermined value η thAlternatively, in this case, the attenuation amount η of the acoustic signal AC1-1 (first acoustic signal) at the position P2 (second position) based on the position P1 (first position) is 12 The attenuation η of the acoustic signal caused by air propagation at position P2 (second position) based on position P1 (first position) is greater than 22 The predetermined value ω th The above. In addition, the position P1 (first position) in the present embodiment is a predetermined position where the sound signal AC1-1 (first sound signal) emitted from the sound hole 121a-1 (first sound hole) reaches. On the other hand, the position P2 (second position) in the present embodiment is a predetermined position farther from the sound signal output device 30 than the position P1 (first position). As described above, the leakage sound component from the sound signal output device 30 is offset. In particular, in the present embodiment, the relative level of the drive unit 11-2 with respect to the drive unit 11-1 can be controlled, so that the leakage sound can be further reduced compared to the case where one drive unit 11 is used as in the first embodiment.

[0362] Furthermore, as described in the configuration example 3 of the circuit unit 31, when the user listens to the sound signal AC1 emitted from the sound hole 121a-1 of the sound signal output device 10-1, by limiting the frequency band of the sound signal emitted from the sound signal output device 10-2 compared to the frequency band of the sound signal emitted from the sound signal output device 10-1, a sufficient sound leakage suppression effect can be expected. For example, as in Example 31-1, when the magnitude of the high frequency side of the sound signal AC2-2 and the sound signal AC1-2 (for example, the high frequency side where sound leakage suppression is difficult by cancellation) is suppressed compared to the magnitude of the high frequency side of the sound signal AC2-1 and the sound signal AC1-1, it is possible to suppress the situation where sound leakage is promoted on the high frequency side. Furthermore, for example, as in Example 31-2, even if the magnitude of the low frequency side of the sound signal AC2-2 and the sound signal AC1-2 is suppressed compared to the magnitude of the low frequency side of the sound signal AC2-1 and the sound signal AC1-1, the influence of sound leakage is small in the use of the low frequency range with weak level such as headphones. Furthermore, even if the driver unit 11 - 2 is smaller or has lower performance than the driver unit 11 - 1 , a sufficient sound leakage suppression effect can be expected.

[0363] [Modification 1 of the third embodiment]

[0364] The sound signal output devices 10-1 and 2 may also be the sound signal output device 10 described in the modification of the first embodiment. Fig.52AAs shown in the example, the position of the sound hole 121a-1 (first sound hole) may be offset to a first eccentric position (a position on the axis A12-1 parallel to the axis A1-1 offset from the axis A1-1 (first central axis) extending in the direction D1-1 (first direction) through the central area of ​​the housing 12-1 (first housing portion). Furthermore, as Fig.52B As illustrated in , when the circumference C1-1 (first circumference) is equally divided into a plurality of first unit arc regions, the sum of the opening areas of the sound holes 123a-1 (second sound holes) arranged along the first arc regions as any one of the first unit arc regions may also be smaller than the sum of the opening areas of the sound holes 123a-1 (second sound holes) arranged along the second arc regions as any one of the first unit arc regions closer to the first eccentric position than the first arc regions. Similarly, for example, the position of the sound hole 121a-2 (fourth sound hole) may also be biased toward a fourth eccentric position (a position on the axis A12-2 parallel to the axis A1-2 and offset from the axis A1-2 (second central axis) extending in the direction D1-2 (fourth direction) through the central region of the shell 10-2 (second shell portion). Furthermore, as Fig.52B As shown in the example, when the circumference C1-2 (the fourth circumference) is equally divided into a plurality of second unit arc regions, the sum of the opening areas of the sound holes 121a-2 (the fourth sound holes) provided along the third arc region as any one of the second unit arc regions may be smaller than the sum of the opening areas of the fourth sound holes provided along the fourth arc region as any one of the second unit arc regions closer to the fourth eccentric position than the third arc region. Even in this case, it is preferred that the sound holes 121a-1 (the first sound holes) and the sound holes 121a-2 (the fourth sound holes) are plane-symmetrical or substantially plane-symmetrical with respect to a reference plane P31 including a straight line parallel or substantially parallel to the straight line (axis A1-1) extending in the direction D1-1 (the first direction). Similarly, the sound holes 123a-1 (the second sound holes) and the sound holes 123a-2 (the third sound holes) are preferably plane-symmetrical or substantially plane-symmetrical with respect to the reference plane P31. More preferably, the housing 12-1 (first housing portion) and the housing 12-2 (second housing portion) are plane-symmetrical or substantially plane-symmetrical with respect to the reference plane P31. In addition, the sound absorbing material described in the modification of the first embodiment may be provided in at least one of the acoustic signal output devices 10-1 and 2.

[0365] [Variation 2 of the Third Embodiment]

[0366] In the third embodiment, the housing 12-1 (first housing portion) of the sound signal output device 10-1 and the housing 12-2 (second housing portion) of the sound signal output device 10-2 may be integrated. Fig.53AAs shown in the example, the shell 12-1 of the sound signal output device 10-1 and the shell 12-2 of the sound signal output device 10-2 may be replaced with an integrated shell 12", and the area AR31 for accommodating the drive unit 11-1 and the area AR32 for accommodating the drive unit 11-2 may be separated by a wall 351 provided inside the shell 12", and the area AR31 is separated from the area AR32. In addition, when area AR31 and area AR32 are separated by the wall 351, it is possible to suppress the mutual cancellation of a part of the sound signal AC1-1 and a part of the sound signal AC1-2, and the mutual cancellation of a part of the sound signal AC2-1 and a part of the sound signal AC2-2 inside the shell 12". Therefore, it is preferred that area AR31 and area AR32 are separated by the wall 351. However, area AR31 and area AR32 may not be separated by the wall 351. That is, a part of the sound signals AC1-1 and AC2-1 emitted from the driver unit 11-1 may not be emitted from any of the sound holes 121a-1, 123a-1, 121a-2, and 123a-2, but may be cancelled out by a part of the sound signals AC1-2 and AC2-2 emitted from the driver unit 11-2 inside the shell 12". Even in this case, the components of the sound signals AC1-1, AC2-1, AC1-2, and AC2-2 that are not canceled out inside the housing 12" are released to the outside from any one of the sound holes 121a-1, 123a-1, 121a-2, and 123a-2. For example, the components of the sound signals AC1-1 and AC2-1 released from the driver unit 11-1 that are not canceled out inside the housing 12" are released to the outside from any one of 121a-1, 123a-1, 121a-2, and 123a-2. Of course, they are canceled out by a portion of the components of other sound signals that are released from any one of the driver units 11-1, 2 and released to the outside from any one of the sound holes 121a-1, 123a-1, 121a-2, and 123a-2. Therefore, even in this case, the sound leakage suppression effect can be obtained. In addition, even when the shell 12-1 and the shell 12-2 are integrated into the shell 12", the sound hole 121a-1 (first sound hole) and the sound hole 121a-2 (fourth sound hole) are preferably plane-symmetrical or approximately plane-symmetrical with respect to the reference plane P31. Similarly, the sound hole 123a-1 (second sound hole) and the sound hole 123a-2 (third sound hole) are preferably plane-symmetrical or approximately plane-symmetrical with respect to the reference plane P31. More preferably, the shell 12-1 (first shell part) and the shell 12-2 (second shell part) are plane-symmetrical or approximately plane-symmetrical with respect to the reference plane P31. In addition, the sound-absorbing material described in the modified example of the first embodiment may be provided inside the shell 12" or in any of the sound holes 121a-1, 121a-2, 123a-1, 123a-2. The rest is the same as the third embodiment or its modified example 1.

[0367] [Variation 3 of the Third Embodiment]

[0368] Instead of the sound signal output devices 10-1 and 2 of the third embodiment, sound signal output devices 20-1 and 2 having the same structure as the sound signal output device 20 of the second embodiment may be used. Fig.53B As shown in the example, the housing 22-1 and the housing 22-2 of the sound signal output device 20-1, 2 are connected by the connecting portion 32. As described in the second embodiment, the housing 22-1 and the housing 23-1 are connected by the waveguides 24-1 and 25-1, and the housing 22-2 and the housing 23-2 are connected by the waveguides 24-2 and 25-2. The circuit unit 31 supplies the output signal I to the drive unit 11-1 accommodated in the housing 23-1, and supplies the output signal II to the drive unit 11-2 accommodated in the housing 23-2. As described in the second embodiment, the sound signal AC1-1 transmitted from the housing 23-1 to the housing 22-1 through the waveguides 24-1 and 25-1 is released from the sound hole 221a-1, and the sound signal AC2-1 is released from the sound hole 223a-1. Similarly, the acoustic signal AC1-2 transmitted from the housing 23-2 to the housing 22-2 through the waveguides 24-2 and 25-2 is released from the sound hole 221a-2, and the acoustic signal AC2-2 is released from the sound hole 223a-2. Other matters are the same as those of the third embodiment or its modified examples 1 and 2, except that the housings 12-1 and 12-2, the sound holes 121a-1, 121a-2, 123a-1, 123a-2, and the walls 121-1, 121-2, 122-1, 122-2, 123-1, and 123-2 are replaced by the housings 22-1 and 22-2, the sound holes 221a-1, 221a-2, 223a-1, 223a-2, and the walls 221-1, 221-2, 222-1, 222-2, 223-1, and 223-2. In addition, the housing 23-1 may be connected to the housing 22-1 through the waveguides 24-1 and 25-1, and connected to the housing 23-1 through the waveguides 24-2 and 25-2. In this case, the circuit unit 31 supplies the output signal I to the drive unit 11-1 accommodated in the housing 23-1. The acoustic signal AC1-1 transmitted from the housing 23-1 to the housing 22-1 through the waveguides 24-1 and 25-1 is released from the sound hole 221a-1, and the acoustic signal AC2-1 is released from the sound hole 223a-1. Similarly, the acoustic signal AC1-2 transmitted from the housing 23-1 to the housing 22-2 through the waveguides 24-2 and 25-2 is released from the sound hole 221a-2, and the acoustic signal AC2-2 is released from the sound hole 223a-2. In addition, the housing 23-1 may be connected to κ housings 22-κ through the waveguides 24-κ and 25-κ. Wherein, κ=1, ..., κ max , κ maxis an integer greater than 2. In this case, the circuit unit 31 supplies the output signal I to the drive unit 11-1 housed in the shell 23-1. The acoustic signal AC1-κ transmitted from the shell 23-1 to the shell 22-κ through the waveguides 24-κ, 25-κ is released from the sound hole 221a-κ, and the acoustic signal AC2-κ is released from the sound hole 223a-κ. In this case, the shell 23-2 and the drive unit 11-2 may be omitted, and the circuit unit 31 does not output the output signal II. Alternatively, the shell 23-2 and the drive unit 11-2 may not be omitted, and the shell 23-2 is further connected to other shells 22-γ through the waveguides 24-γ, 25-γ. Among them, γ=κ max +1,…,γ max , γ max is greater than κ max In this case, the output signal II output from the circuit unit 31 is further supplied to the drive unit 11-2 housed in the housing 22-2, and the acoustic signal AC1-γ transmitted from the housing 23-2 through the waveguides 24-γ and 25-γ to the housing 22-γ is released from the sound hole 221a-γ, and the acoustic signal AC2-γ is released from the sound hole 223a-γ. That is, the acoustic signal AC1-1 (first acoustic signal) released from any one of the single or multiple drive units can be released from the sound hole 221a-1 (first sound hole) to the outside. In addition, the acoustic signal AC2-1 (second acoustic signal) released from any one of the single or multiple drive units can be released from the sound hole 123a-1 (second sound hole) to the outside. In addition, the acoustic signal AC2-2 (third acoustic signal) released from any one of the single or multiple drive units can be released from the sound hole 123a-2 (third sound hole). In addition, the sound signal AC1-2 (fourth sound signal) emitted from any one of the single or multiple drive units can be emitted to the outside from the sound hole 221a-2 (fourth sound hole). That is, the sound signal AC1-1 (first sound signal) and the sound signal AC2-2 (third sound signal) can be the same signal emitted from the same drive unit, or they can be different signals emitted from different drive units. Similarly, the sound signal AC2-1 (second sound signal) and the sound signal AC1-2 (fourth sound signal) can be the same signal emitted from the same drive unit, or they can be different signals emitted from different drive units.

[0369] [Fourth Embodiment]

[0370] In the fourth embodiment, an example is shown in which a sound signal output device that is worn on both ears without sealing the external auditory canal of the user emits a monaural sound signal with mutually reversed phases toward the left and right ears. From such a sound signal output device, a portion of the monaural sound signal is emitted not only toward the external auditory canal side of the user but also toward the outside of the user. However, since the monaural sound signals with mutually reversed phases are emitted, the monaural sound signals propagating toward the outside of the user cancel each other out, thereby reducing sound leakage.

[0371] like Fig.54A As shown in the example, the sound signal output device 4 of this embodiment has: an sound signal output unit 40-1 (first sound signal output unit) worn on the right ear (one ear) 1010 of the user 1000; an sound signal output unit 40-2 (second sound signal output unit) worn on the left ear (the other ear) 1020; and a circuit unit 41.

[0372] <Circuit section 41>

[0373] The circuit unit 41 is a circuit that uses an input signal that is an electrical signal representing a monaural sound signal as an input, generates and outputs an output signal I supplied to the sound signal output unit 40-1 and an output signal II supplied to the sound signal output unit 40-2. The circuit unit 41 of this embodiment includes signal output units 411, 412 and a phase reversal unit 413. The input signal is input to the phase reversal unit 413 and the signal output unit 412. The phase reversal unit 413 outputs an output signal I (first output signal) that is an inverted signal of the input signal or an approximate signal of the inverted signal. The signal output unit 411 (first signal output unit) outputs the output signal I (first output signal) to the sound signal output unit 40-1 (first sound signal output unit). That is, the signal output unit 411 (first signal output unit) outputs an output signal I (first output signal) which is used to output a monaural sound signal MAC1 (first monaural sound signal) from the sound signal output unit 40-1 (first sound signal output unit) worn on the right ear (one ear) 1010. In addition, the signal output unit 412 directly outputs the input signal as an output signal II (second output signal) to the sound signal output unit 40-2 (second sound signal output unit). That is, the signal output unit 412 outputs an output signal II (second output signal) which is used to output a monaural sound signal MAC2 (second monaural sound signal) from the sound signal output unit 40-2 (second sound signal output unit) worn on the left ear (the other ear) 1020.

[0374] <Acoustic Signal Output Units 40-1, 40-2>

[0375] The sound signal output units 40-1 and 40-2 are sound listening devices that are worn on both ears without sealing the external auditory canal of the user. The output signal I is input to the sound signal output unit 40-1, and the sound signal output unit 40-1 converts the output signal I into a monaural sound signal MAC1 (a phase that is the same as or substantially the same as the phase of the monaural sound signal MAC1 is expressed as "+") and emits it to the external auditory canal of the right ear 1010. The output signal II is input to the sound signal output unit 40-2, and the sound signal output unit 40-2 converts the output signal II into a monaural sound signal MAC2 (a phase that is the same as or substantially the same as the phase of the monaural sound signal MAC2 is expressed as "-") and emits it to the external auditory canal of the left ear 1020. Here, the monaural sound signal MAC2 is an inverted signal of the monaural sound signal MAC1 or a signal that is similar to the inverted signal of the monaural sound signal MAC1. However, even if the phases of the sound signals heard by the left and right ears are reversed, there is almost no problem in audio-visual experience. In addition, a part of the monaural sound signal MAC1 and the monaural sound signal MAC2 are also emitted to the outside of both ears, but since the monaural sound signal MAC1 and the monaural sound signal MAC2 are in opposite or substantially opposite phases to each other, they cancel each other out. That is, a part of the emitted monaural sound signal MAC1 (first monaural sound signal) and a part of the emitted monaural sound signal MAC2 (a part of the second monaural sound signal) cancel each other out by mutual interference on the outer side (outer side of the user 1000, i.e., the opposite side of the right ear 1010 side) of the sound signal output unit 40-1 (first sound signal output unit) worn on the right ear 1010 (one ear) and / or on the outer side (outer side of the user 1000, i.e., the opposite side of the left ear 1020 side) of the sound signal output unit 40-2 (second sound signal output unit) worn on the left ear 1020 (the other ear). That is, as described above, the monaural sound signal MAC1 (first monaural sound signal) is output from the sound signal output unit 40-1 (first sound signal output unit), and the monaural sound signal MAC2 (second monaural sound signal) is output from the sound signal output unit 40-2 (second sound signal output unit). In this case, the attenuation rate η of the monaural sound signal MAC1 (first monaural sound signal) at the position P2 (second position) with respect to the position P1 (first position) is 11 The attenuation rate η of the acoustic signal due to air propagation at position P2 (second position) based on position P1 (first position) is smaller than that at position P2 (second position). 21 The predetermined value η th Alternatively, in this case, the attenuation amount η of the first monaural sound signal at position P2 (second position) based on position P1 (first position) is 12The attenuation η of the acoustic signal caused by air propagation at position P2 (second position) based on position P1 (first position) is greater than 22 The predetermined value ω th Above. Among them, the position P1 (first position) of this embodiment is a predetermined position where the monaural sound signal MAC1 (first monaural sound signal) reaches. In addition, the position P2 (second position) of this embodiment is a position farther from the sound signal output unit 40-1 (first sound signal output unit) than the position P1 (first position). As a result, sound leakage is suppressed.

[0376] [Variation 1 of the Fourth Embodiment]

[0377] The acoustic signal output device 10 of the first embodiment or its modified example may be used instead of the acoustic signal output units 40 - 1 and 40 - 2 , and the acoustic signal output device 20 of the second embodiment or its modified example may be used instead of the acoustic signal output units 40 - 1 and 40 - 2 .

[0378] like Fig.54B As shown in the example, the sound signal output device 4' of this variant example comprises: an sound signal output device 10-1 (a first sound signal output unit) worn on the right ear (one ear) 1010 of the user 1000; an sound signal output device 10-2 (a second sound signal output unit) worn on the left ear (the other ear) 1020; and a circuit unit 41, or comprises: an sound signal output device 20-1 (a first sound signal output unit) worn on the right ear (one ear) 1010 of the user 1000; an sound signal output device 20-2 (a second sound signal output unit) worn on the left ear (the other ear) 1020; and a circuit unit 41.

[0379] The sound signal output device 10-1 or 20-1 (first sound signal output unit) includes a driving unit 11-1 (first driving unit) that emits a monaural sound signal MAC1-1 (first sound signal, first monaural sound signal) in the direction D1-1 (one side), and emits a monaural sound signal MAC2-1 (first sound signal, first monaural sound signal) which is an inverted signal of the monaural sound signal MAC1-1 or a signal similar to the inverted signal of the monaural sound signal MAC1-1 in the other side of the direction D1-1. Second sound signal); and a shell 12-1 or 22-1 (first shell), which is provided with a single or multiple sound holes 121a-1 or 221a-1 (first sound hole) on the wall for exporting the monaural sound signal MAC1-1 (first sound signal) emitted from the driving unit 11-1 to the outside, and a single or multiple sound holes 123a-1 or 223a-1 (second sound hole) for exporting the monaural sound signal MAC2-1 (second sound signal) emitted from the driving unit 11-1 to the outside.

[0380] The sound signal output device 10-2 or 20-2 (second sound signal output unit) includes: a driving unit 11-2 (second driving unit) that emits a monaural sound signal MAC1-2 (fourth sound signal, second monaural sound signal) that is the same as or similar to the monaural sound signal MAC2-1 (second sound signal) in the direction D1-2 (one side), and emits a monaural sound signal MAC1-2 (fourth sound signal, second monaural sound signal) that is the same as or similar to the monaural sound signal MAC2-1 (second sound signal) in the other side of the direction D1-2. 2-2 (third sound signal); and shells 12-2, 22-2 (second shell), provided on the wall with a single or multiple sound holes 123a-2 or 223a-2 (third sound hole) for exporting the monaural sound signal MAC2-2 (third sound signal) emitted from the driving unit 11-2 to the outside and a single or multiple sound holes 121a-2 or 221a-2 (fourth sound hole) for exporting the monaural sound signal MAC1-2 (fourth sound signal) emitted from the driving unit 11-2 to the outside.

[0381] In this modification, the acoustic signal AC1-1 (first acoustic signal) is a monaural acoustic signal MAC1-1 (first monaural acoustic signal), the acoustic signal AC2-1 is a monaural acoustic signal MAC2-1, the acoustic signal AC1-2 (fourth acoustic signal) is a monaural acoustic signal MAC1-2 (second monaural acoustic signal), and the acoustic signal AC2-2 is a monaural acoustic signal MAC2-2. The detailed structures of the other acoustic signal output devices 10-1 and 10-2 are the same as those of the acoustic signal output device 10 of the first embodiment or its modification. In addition, the detailed structures of the acoustic signal output devices 20-1 and 20-2 are the same as those of the acoustic signal output device 20 of the second embodiment or its modification.

[0382] When the sound signal output device 4' is worn on both ears, the sound hole 121a-1 or 221a-1 of the sound signal output device 10-1 or 20-1 faces the right ear 1010 (i.e., the D1-1 direction faces the right ear 1010), and the sound hole 121a-2 or 121a-2 of the sound signal output device 10-2 or 20-2 faces the left ear 1020 (i.e., the D1-2 direction faces the left ear 1020).

[0383] A monaural acoustic signal MAC1-1 (first monaural acoustic signal) is emitted from the sound hole 121a-1 or 221a-1 of the acoustic signal output device 10-1 or 20-1 (first acoustic signal output unit) to the external auditory canal of the right ear 1010. A monaural acoustic signal MAC1-2 (second monaural acoustic signal) is emitted from the sound hole 121a-2 or 221a-2 of the acoustic signal output device 10-2 or 20-2 (second acoustic signal output unit) to the external auditory canal of the left ear 1020. Here, the monaural acoustic signal MAC1-2 is an inverted phase signal of the monaural acoustic signal MAC1-1 or a signal similar to the inverted phase signal of the monaural acoustic signal MAC1-1. However, even if the phases of the acoustic signals heard by the left and right ears are reversed, there is almost no problem in audio-visual experience. In addition, a part of the monaural sound signal MAC1-1 and the monaural sound signal MAC1-2 are also emitted to the outside of both ears, but since the monaural sound signal MAC1-1 and the monaural sound signal MAC1-2 are in opposite or substantially opposite phases to each other, they cancel each other out. That is, a part of the emitted monaural sound signal MAC1-1 (first monaural sound signal) and a part of the emitted monaural sound signal MAC1-2 (second monaural sound signal) cancel each other out by mutual interference on the outer side (outer side of the user 1000, i.e., the opposite side of the right ear 1010 side) of the sound signal output device 10-1 or 20-1 (first sound signal output unit) worn on the right ear 1010 (one ear) and / or on the outer side (outer side of the user 1000, i.e., the opposite side of the left ear 1020 side) of the sound signal output device 10-2 or 20-2 (second sound signal output unit) worn on the left ear 1020 (the other ear). Furthermore, a monaural sound signal MAC2-1 is emitted from the sound hole 123a-1 or 223a-1 of the sound signal output device 10-1 or 20-1 (first sound signal output unit). A portion of the emitted monaural sound signal MAC2-1 cancels a portion of the monaural sound signal MAC1-1 emitted from the sound hole 121a-1 or 221a-1. Furthermore, a monaural sound signal MAC2-2 is emitted from the sound hole 123a-2 or 223a-2 of the sound signal output device 10-2 or 20-2 (second sound signal output unit). A portion of the emitted monaural sound signal MAC2-2 cancels a portion of the monaural sound signal MAC1-2 emitted from the sound hole 121a-2 or 221a-2. As a result, sound leakage is suppressed.

[0384] [Variation 2 of the Fourth Embodiment]

[0385] The output signal I and the output signal II in the fourth embodiment or the first variation of the fourth embodiment may be opposite. That is, the input signal input to the circuit unit 41 may be input to the phase reversal unit 413 and the signal output unit 412, the phase reversal unit 413 may output the output signal II (second output signal) which is an inverted signal of the input signal or a signal approximating the inverted signal to the sound signal output unit 40-2 (second sound signal output unit), and the signal output unit 412 may directly output the input signal as the output signal I (first output signal) to the sound signal output unit 40-1 (first sound signal output unit).

[0386] [Fifth Embodiment]

[0387] In the fifth embodiment, a wearing method of an ear-worn type sound signal output device is illustrated. As mentioned above, in the conventional wearing method, there are sometimes problems such as a heavy burden on the ear and difficulty in stable wearing. In this embodiment, a new wearing method of the sound signal output device for solving such problems is illustrated.

[0388] <Wearing method 1>

[0389] use FIG. 55A to FIG. 56D To illustrate wearing method 1. FIG. 55A to FIG. 55C As shown in the example, the sound signal output device 2100 of the wearing mode 1 includes: a housing 2112 that emits a sound signal; a wearing part 2121 (first wearing part) that holds the housing 2112 and is configured to be worn on the upper part 1022 (first auricle part) of the auricle 1020 as a part of the auricle 1020; and a wearing part 2122 (second wearing part) that holds the housing 2112 and is configured to be worn on the middle part 1023 (second auricle part) of the auricle 1020 that is different from the upper part 1022 (first auricle part) of the auricle 1020. In addition, the middle part 1023 is the middle part between the upper part 1022 (helix side) and the lower part 1024 (earlobe side) of the auricle 1020. In addition, in the present embodiment, an example is shown in which the auricle 1020 is a human auricle, but the auricle 1020 may also be the auricle of an animal other than a human (such as a chimpanzee).

[0390] The shell 2112 of this example can be any one of the shells 12, 12", 22 illustrated in the first to fourth embodiments and their modified examples, or can be the shell of an audio signal output device that emits an audio signal, such as an existing earphone. When the audio signal output device 2100 is worn, the shell 2112 is configured so that the sound hole 2112a faces the external auditory canal 1021 and does not block the external auditory canal 1021.

[0391] The wearing portion 2121 (first wearing portion) of this example has a fixing portion 2121a (first fixing portion) that grasps the helix 1022a (end portion) of the upper portion 1022 (first auricle portion) of the auricle 1020, and a supporting portion 2121b that fixes the fixing portion 2121a (first fixing portion) to the housing 2112. One end of the supporting portion 2121b holds a specific area of ​​the outer wall of the fixing portion 2121a, and the other end of the supporting portion 2121b holds a specific area H1 (first holding area) of the outer wall of the housing 2112. One end of the supporting portion 2121b can be fixed to a specific area of ​​the wall of the fixing portion 2121a, or it can be integrated with the wall of the fixing portion 2121a in the specific area. Similarly, the other end of the supporting portion 2121b can be fixed to a specific area H1 of the outer wall of the housing 2112, or it can be integrated with the outer wall of the housing 2112 in the specific area H1. In this way, the support portion 2121b holds the housing 2112 from the outer side (first outer side) of a specific region H1 of the wall portion of the housing 2112. In the case of this example, when the fixing portion 2121a is worn on the helix 1022a, the outer side (first outer side) of the region H1 becomes the upper part 1022 side of the auricle 1020. Here, the fixing portion 2121a (first fixing portion) is configured to grip the helix 1022a of the upper part 1022 (first auricle part) of the auricle 1020 from the upper side of the auricle 1020. In addition, the housing 2112 is configured to be suspended by the wearing portion 2121 (first wearing portion) including the fixing portion 2121a (first fixing portion) gripping the helix 1022a. That is, the fixing portion 2121a grips the helix 1022a from the upper side of the auricle 1020, and the housing 2112 is suspended by the other end of the supporting portion 2121b that holds the fixing portion 2121a at one end. The reaction force relative to the weight of the housing 2112 suspended in this way is supported by the inner wall surface of the fixing portion 2121a. For example, the reaction force is supported by the inner wall surface of the fixing portion 2121a that is configured to be perpendicular or approximately perpendicular to the direction of the reaction force. In the case of such a structure, even if the gripping force of the fixing portion 2121a is small, the weight of the housing 2112 can be supported. The smaller the gripping force of the fixing portion 2121a, the smaller the burden on the auricle 1020, and thus the burden on the ear can be reduced. In addition, the specific shape of the fixing portion 2121a can also be any shape. An example of the fixing portion 2121a is a member having a hollow shape with a C-shaped or U-shaped cross section, configured to hold the helix 1022a in a state where the helix 1022a contacts the inner wall surface 2121aa (for example, FIG. 56A to FIG. 56D ). For example, the fixing portion 2121a having an ear cuff type shape can be exemplified.

[0392] The wearing portion 2122 (second wearing portion) of this example has a fixing portion 2122a (second fixing portion) that grasps the end of the middle portion 1023 (second auricle portion) of the auricle 1020, and a supporting portion 2122b that fixes the fixing portion 2122a (second fixing portion) to the shell 2112. One end of the supporting portion 2122b holds a specific area of ​​the outer wall of the fixing portion 2122a, and the other end of the supporting portion 2122b holds a specific area H2 (second holding area) of the outer wall of the shell 2112. The area H2 is different from the above-mentioned area H1. One end of the supporting portion 2122b can be fixed to a specific area of ​​the wall of the fixing portion 2122a, or it can be integrated with the wall of the fixing portion 2122a in the specific area. Similarly, the other end of the supporting portion 2122b can be fixed to a specific area H2 of the outer wall of the shell 2112, or it can be integrated with the outer wall of the shell 2112 in the specific area H2. In this way, the support portion 2122b holds the housing 2112 from the outer side (the second outer side different from the first outer side) of a specific region H2 of the wall portion of the housing 2112. In the case of this example, when the fixing portion 2122a is worn at the end of the middle portion 1023 of the auricle 1020, the outer side (the second outer side) of the region H2 becomes the middle portion 1023 side of the auricle 1020. In this way, the housing 2112 is held at the upper portion 1022 of the auricle 1020 from the outer side (the first outer side) of the region H1 by the wearing portion 2121 (the first wearing portion) as described above, and is also held at the middle portion 1023 of the auricle 1020 from the outer side (the second outer side different from the first outer side) of the region H2 by the wearing portion 2122 (the second wearing portion). As a result, the position of the housing 2112 worn on the auricle 1020 is stabilized. In addition, the housing 2112 is held at different positions (upper part 1022 and middle part 1023) of the auricle 1020 by the wearing part 2121 (first wearing part) and the wearing part 2122 (second wearing part), so that the burden on the auricle 1020 caused by wearing can be dispersed. Furthermore, the housing 2112 is worn on the auricle 1020 by the wearing parts 2121 and 2122 that grasp the ends of the auricle 1020. Such wearing parts 2121 and 2122 do not interfere with the temples (temples) and the ropes of the mask hooked on the back side of the auricle 1020. In addition, the specific shape of the fixing part 2122a can also be any shape. An example of the fixing part 2122a is a member having a hollow shape with a C-shaped or U-shaped cross section and configured to grip the middle portion 1023 of the auricle 1020 when the helix 1022a is in contact with the inner wall surface 2122aa. For example, the fixing part 2122a having an earmuff shape can be exemplified.

[0393] There is no limitation on the material constituting the wearing portion 2121 and the wearing portion 2122. The wearing portion 2121 and the wearing portion 2122 may be formed of a rigid body such as synthetic resin or metal, or may be formed of an elastic body such as rubber.

[0394] <Wearing method 2>

[0395] use FIG. 57A to FIG. 57C Example wearing method 2. FIG. 57A to FIG. 57C As shown in the example, the sound signal output device 2100' of wearing mode 2 is further provided with a wearing portion 2123 (second wearing portion) in addition to the sound signal output device 2100 of wearing mode 1, and the wearing portion 2123 (second wearing portion) is configured to be worn on the lower portion 1024 (second auricle portion) which is a part of the auricle 1020 different from the upper portion 1022 (first auricle portion) and the middle portion 1023 (second auricle portion) of the auricle 1020.

[0396] The wearing portion 2123 (second wearing portion) of this example has a fixing portion 2123a (second fixing portion) that grasps the end of the lower portion 1024 (second auricle portion) of the auricle 1020 and a supporting portion 2123b that fixes the fixing portion 2123a (second fixing portion) to the shell 2112. One end of the supporting portion 2123b holds a specific area of ​​the outer wall of the fixing portion 2123a, and the other end of the supporting portion 2123b holds a specific area H3 (second holding area) of the outer wall of the shell 2112. Area H3 is different from the above-mentioned area H1 and area H2. One end of the supporting portion 2123b can be fixed to a specific area of ​​the wall of the fixing portion 2123a, or it can be integrated with the wall of the fixing portion 2123a in the specific area. Similarly, the other end of the supporting portion 2123b can be fixed to a specific area H3 of the outer wall of the shell 2112, or it can be integrated with the outer wall of the shell 2112 in the specific area H3. In this way, the support portion 2123b holds the housing 2112 from the outer side (the second outer side different from the first outer side) of a specific region H3 of the wall portion of the housing 2112. In the case of this example, when the fixing portion 2123a is worn at the end of the lower portion 1024 of the auricle 1020, the outer side (the second outer side) of the region H3 becomes the lower portion 1024 side of the auricle 1020. In this way, the housing 2112 is also held by the wearing portion 2123 (the second wearing portion) from the outer side (the second outer side different from the first outer side) of the region H3 to the lower portion 1024 of the auricle 1020. As a result, the position of the housing 2112 worn on the auricle 1020 is more stable. In addition, the housing 2112 is held at different parts of the auricle 1020 (upper part 1022, middle part 1023 and lower part 1024) through the wearing part 2121 (first wearing part), the wearing part 2122 (second wearing part) and the wearing part 2123 (second wearing part), so that the burden on the auricle 1020 caused by wearing can be dispersed. Furthermore, the housing 2112 is worn on the auricle 1020 through the wearing parts 2121, 2122, 2123 that grasp the end of the auricle 1020. Such wearing parts 2121, 2122, 2123 do not interfere with the glasses legs or the rope of the mask hooked on the back side of the auricle 1020. In addition, the specific shape of the fixing part 2123a can also be any shape. An example of the fixing part 2123a is a member having a hollow shape with a C-shaped or U-shaped cross section, and configured to grip the lower part 1024 of the auricle 1020 in a state where the helix 1022a is in contact with the inner wall surface 2123aa. For example, the fixing part 2123a having an earmuff shape can be exemplified. The material constituting the wearing part 2123 is also not limited.

[0397] <Wearing method 3>

[0398] The acoustic signal output device 2100 ′ of wearing style 2 may be configured such that the wearing portion 2122 is omitted.

[0399] <Wearing method 4>

[0400] like Fig.58 As in the example of the sound signal output device 2200 in FIG. 1 , the wearing portion 2121 of the sound signal output device 2100 of the wearing mode 1 may be replaced by a wearing portion 2224 of a type (glasses-leg type) that is hooked on the back side of the upper portion 1022 of the auricle 1020. The wearing portion 2224 is a rod-shaped member. One end side of the wearing portion 2224 is bent to be hooked on the back side of the upper portion 1022 of the auricle 1020, and the other end holds a specific area H1 (first holding area) of the outer wall of the housing 2112. The other end of the wearing portion 2224 may be fixed to the specific area H1 of the outer wall of the housing 2112, or may be integrated with the outer wall of the housing 2112 in the specific area H1. Similarly, the wearing portion 2121 of the sound signal output device 2100' of the wearing modes 2 and 3 may be replaced by a wearing portion 2224 of a type that is hooked on the back side of the upper portion 1022 of the auricle 1020. In addition, the material constituting the wearing portion 2224 is not limited.

[0401] <Wearing method 5>

[0402] like Fig.59A, the wearing portion 2122 of the sound signal output device 2100 of wearing mode 1 may be replaced by a wearing portion 2124 (second wearing portion) that clamps the end of the middle portion 1023 (second auricle portion) of the auricle 1020. The wearing portion 2124 (second wearing portion) includes a fixing portion 2124a (second fixing portion) that clamps the end of the middle portion 1023 (second auricle portion) of the auricle 1020 and a supporting portion 2124b that fixes the fixing portion 2124a (second fixing portion) to the housing 2112. One end of the supporting portion 2124b holds the end of the fixing portion 2124a, and the other end of the supporting portion 2124b holds a specific area H2 (second holding area) of the outer wall of the housing 2112. One end of the supporting portion 2124b may be fixed to the end of the fixing portion 2124a, or may be integrated with the end of the fixing portion 2124a. Similarly, the other end of the support portion 2124b can be fixed to a specific region H2 of the outer wall of the housing 2112, or can be integrated with the outer wall of the housing 2112 in the specific region H2. In this way, the support portion 2124b holds the housing 2112 from the outer side (the second outer side different from the first outer side) of the specific region H2 of the wall of the housing 2112. In this way, the housing 2112 is held on the upper part 1022 of the auricle 1020 from the outer side (the first outer side) of the region H1 by the wearing portion 2121 (the first wearing portion) as described above, and is also held on the middle part 1023 of the auricle 1020 from the outer side (the second outer side different from the first outer side) of the region H2 by the wearing portion 2124 (the second wearing portion). As a result, the position of the housing 2112 worn on the auricle 1020 is stabilized. In this case, the shell 2112 is also held at different positions (upper part 1022 and middle part 1023) of the auricle 1020 by the wearing part 2121 (first wearing part) and the wearing part 2124 (second wearing part), so that the burden on the auricle 1020 caused by wearing can be dispersed. Furthermore, the wearing parts 2121 and 2124 will not interfere with the glasses legs or the ropes of the mask hooked on the back side of the auricle 1020. In addition, the clamping fixing part 2124a (second fixing part) can also be configured to clamp the lower part 1024 of the auricle 1020 instead of the middle part 1023 of the auricle 1020. In addition, the specific shape of the fixing part 2124a can also be any shape. For example, the fixing part 2124a can be a clamp-shaped clamping mechanism or an integrated leaf spring. In addition, the material constituting the wearing part 2124 is not limited.

[0403] <Wearing method 6>

[0404] like Fig.59BAs in the example of the sound signal output device 2400 shown in FIG. 1 , the wearing portion 2121 of the sound signal output device 2300 of the wearing mode 5 may be replaced with a wearing portion 2224 of a type that is hooked on the back side of the upper portion 1022 of the auricle 1020. The structure of the wearing portion 2224 is the same as that of the wearing mode 4.

[0405] <Wearing method 7>

[0406] In the case where the shell 2112 is the shell 12, 12", 22 illustrated in the first to fourth embodiments and their variations, the opening area of ​​the sound holes 123a, 223a (second sound holes) arranged in the area (blocking area) where the sound signal AC1 (first sound signal) emitted from the sound holes 121a, 221a (first sound hole) of the shell 12, 12", 22 is blocked by the wearing part 2121, 2122, 2123, 2124, 2224 or in the vicinity thereof can be set to be smaller than the opening area of ​​the sound holes 123a, 223a (second sound holes) arranged at a position away from the blocking area. As described above, a portion of the sound signal AC1 (first sound signal) emitted from the sound holes 121a, 221a (first sound hole) of the housing 12, 12", 22 is offset by the sound signal AC2 (second sound signal) emitted from the sound holes 123a, 223a (second sound hole), thereby suppressing sound leakage. Here, in the shielding area, the sound pressure of the sound signal AC1 (first sound signal) leaking to the outside is smaller than that in other areas. By correspondingly reducing the opening area of ​​the sound holes 123a, 223a (second sound hole) provided in the shielding area or in the vicinity thereof, the sound leakage to the outside can be reduced. The distribution of the sound pressure of the acoustic signal AC1 (first acoustic signal) is balanced with the distribution of the sound pressure of the acoustic signal AC2 (second acoustic signal) released from the sound holes 123a and 223a (second sound holes). That is, the acoustic signal AC1 (first acoustic signal) is released from the sound holes 121a and 221a (first sound holes), and the acoustic signal AC2 (second acoustic signal) is released from the sound holes 123a and 223a (second sound holes). The distribution of the sound pressure can be balanced so that the attenuation rate η of the acoustic signal AC1 (first acoustic signal) at the position P2 (second position) based on the position P1 (first position) in this case is 11 The attenuation rate η of the acoustic signal due to air propagation at position P2 (second position) based on position P1 (first position) is smaller than that at position P2 (second position). 21 The predetermined value η th Alternatively, the balance of the sound pressure distribution can be achieved so that the attenuation amount η of the acoustic signal AC1 (first acoustic signal) at the position P2 (second position) based on the position P1 (first position) in this case is 12The attenuation η of the acoustic signal caused by air propagation at position P2 (second position) based on position P1 (first position) is greater than 22 The predetermined value ω th The above. In addition, the position P1 (first position) here is a predetermined position where the sound signal AC1 (first sound signal) emitted from the sound hole 221a (first sound hole) reaches. In addition, the position P2 (second position) here is a predetermined position farther from the sound signal output device than the position P1 (first position). As a result, sound leakage can be effectively suppressed.

[0407] The following example is described below: the shell 2112 is the shell 12 of the first embodiment or its modified example, and the shell 12 (shell 2112) is held in the wearing part 2121, 2122 of the wearing method 1. However, this does not limit the present invention. The shell 2112 may also be the shell 12, 12", 22 illustrated in the second to fourth embodiments and their modified examples, and the shell 12, 12", 22 may also be held in the wearing part 2121, 2122, 2123, 2124, 2224 of any one of the wearing methods 2 to 6. In this case, the following structure can also be applied.

[0408] like Fig.60AAs shown in the example, the sound signal output device 2100 in this case includes a driving unit 11 that emits a sound signal AC1 (first sound signal) to one side (the D1 direction side) and emits a sound signal AC2 (second sound signal) that is an inverted signal of the sound signal AC1 (first sound signal) or a signal similar to the inverted signal to the other side (the D2 direction side). As described above, the walls 121 and 123 of the housing 12 are provided with a single or multiple sound holes 121a (first sound holes) that lead the sound signal AC1 (first sound signal) emitted from the driving unit 11 to the outside, and a single or multiple sound holes 123a (second sound holes) that lead the sound signal AC2 (second sound signal) emitted from the driving unit 11 to the outside. As described above, a part of the sound signal AC2 (second sound signal) emitted from the sound hole 123a (second sound hole) cancels a part of the sound signal AC1 (first sound signal) emitted from the sound hole 121a (first sound hole), thereby suppressing sound leakage. As described above, the support portion 2121b of the wearing portion 2121 (first wearing portion) holds the region H1 (first holding region) of the wall portion 123 of the shell 12 (shell 2112), and the support portion 2122b of the wearing portion 2122 (second wearing portion) holds the region H2 (second holding region) of the wall portion 123 of the shell 12 (shell 2112). Here, the sound hole 121a (first sound hole) is arranged on one side (D1 direction side) of the space divided by the virtual plane P51 passing through the region H1 (first holding region) and the wearing portion 2122 (second wearing portion). On the other hand, the sound hole 123a (second sound hole) is arranged on the other side (D2 direction side) of the space divided by the virtual plane P51. Here, the opening area of ​​the sound hole 123a (second sound hole) is reduced, and the sound hole 123a (second sound hole) is set in or near the blocking area AR51 where the sound signal AC1 (first sound signal) is blocked by the support part 2121b of the wearing part 2121 (first wearing part) or the support part 2122b of the wearing part 2122 (second wearing part). Fig.60BAs shown in the example, the sound hole 123a (second sound hole) is set along the aforementioned circumference C1. In addition, it is assumed that the surface of the wall portion 123 of the shell 12 is equally divided into a plurality of unit area regions (in this example, unit area regions C5-1, C5-2, C5-3, and C5-4) along the circumference C1. In this example, the number of sound holes 123a (second sound holes) set in the first unit area region (in this example, unit area regions C5-2 and C5-3) that is any one of the unit area regions including the shielding area AR51 is less than the number of sound holes 123a (second sound holes) set in the second unit area region (in this example, unit area regions C5-1 and C5-4) that is any one of the unit area regions not including the shielding area AR51. In this case, the total opening area of ​​the sound hole 123a (second sound hole) provided in the first unit area (in this example, the unit area C5-2 and C5-3) which is any one of the unit area including the shielding area AR51 is smaller than the total opening area of ​​the sound hole 123a (second sound hole) provided in the second unit area (in this example, the unit area C5-1 and C5-4) which is any one of the unit area not including the shielding area AR51. Thus, sound leakage can be effectively suppressed.

[0409] like Fig.61A as well as Fig.61B As shown in the example, the number of sound holes 123a (second sound holes) provided in the first unit area region (in this example, the unit area regions C5-2 and C5-3) including the shielding area AR51 may be less than the number of sound holes 123a (second sound holes) provided in the second unit area region (in this example, the unit area regions C5-1 and C5-4) not including the shielding area AR51, and further, the sound holes 123a having an opening area larger than that of the first unit area region may be provided in the second unit area region. In addition, the number of sound holes 123a in the first unit area region and the second unit area region may be equal, and the opening area of ​​each sound hole 123a provided in the first unit area region may be smaller than the opening area of ​​each sound hole 123a provided in the second unit area region. In this case, the total opening area of ​​the sound holes 123a (second sound holes) provided in the first unit area region (in this example, the unit area regions C5-2 and C5-3) is smaller than the total opening area of ​​the sound holes 123a (second sound holes) provided in the second unit area region (in this example, the unit area regions C5-1 and C5-4). In this way, sound leakage can also be effectively suppressed.

[0410] <Wearing method 8>

[0411] use Fig.62 , Fig.63A , Fig.63B Example wearing method 8. Fig.62 as well as Fig.63A As illustrated in FIG. 8 , the sound signal output device 2500 of wearing style 8 includes a housing 2112 for emitting sound signals and a wearing portion 2221 that holds the housing 2112 and is configured to be worn on the auricle 1020 .

[0412] The wearing portion 2221 includes: a fixing portion 2221a having a concave inner wall surface 2221aa configured to fit with the upper portion 1022 of the auricle 1020; and a shielding wall 2221b configured to cover only a portion of the auricle 1020 when the inner wall surface 2221aa side of the fixing portion 2221a fits with the upper portion 1022 of the auricle 1020. The fixing portion 2221a of this example has a hollow structure that accommodates at least a portion of the upper portion 1022 of the auricle 1020 (for example, the helix 1022a). If the burden on the auricle 1020 is considered, the inner wall surface 2221aa of the fixing portion 2221a is preferably a curved surface. However, this does not limit the present invention. The shielding wall 2221b is a plate having a flat or curved wall surface. The shielding wall 2221b of this example is configured in such a shape that when the inner wall surface 2221aa side of the fixing portion 2221a is fitted with the upper portion 1022 of the auricle 1020, the shielding wall 2221b covers the upper portion 1022 of the auricle 1020 and opens the lower portion 1024 of the auricle 1020 to the outside. That is, the end 2221c (the end on the opposite side from the fixing portion 2221a) side of the shielding wall 2221b is the opening portion O51. The opening portion O51 is provided at a position where the lower portion 1024 of the auricle 1020 is opened to the outside when the upper portion 1022 of the auricle 1020 is fitted with the inner wall surface 2221aa side of the fixing portion 2221a. The material constituting the wearing portion 2221 is also not limited.

[0413] The housing 2112 of this example may be any of the housings 12, 12", 22 illustrated in the first to fourth embodiments and their modified examples, or may be the housing of an audio signal output device that emits an audio signal, such as an existing earphone. The housing 2112 is held on the inner wall surface 2221bb side of the shielding wall 2221b, and the sound hole 2112a that emits the audio signal opens in the direction opposite to the inner wall surface 2221bb. When the audio signal output device 2500 is worn on the auricle 1020, the outer wall surface 2221ba side of the shielding wall 2221b faces outward, and the inner wall surface 2221bb side of the shielding wall 2221b faces inward ( The sound hole 2112a of the shell 2112 held on the inner wall surface 2221bb faces the external auditory canal 1021, and the shell 2112 is configured so as not to block the external auditory canal 1021. At this time, since the sound hole 2112a is configured on the inner side of the shielding wall 2221b, the influence of external noise can be suppressed, and the leakage of the sound signal emitted from the sound hole 2112a can also be suppressed. Furthermore, since the shielding wall 2221b only covers a part of the auricle 1020 (the lower part 1024 side of the auricle 1020 is not blocked), the external sound is not completely blocked, and the user can also hear the external sound.

[0414] <Wearing Style 9>

[0415] like Fig.64 As shown in the example, the sound signal output device 2500' of the wearing mode 9 is a modified example of the sound signal output device 2500 of the wearing mode 8, and the wearing portion 2221 of the sound signal output device 2500 is replaced by the wearing portion 2221'. The wearing portion 2221' is a member in which the shielding wall 2221b of the wearing portion 2221 is replaced by the shielding wall 2221b'. The shielding wall 2221b' is configured in a shape in which a part of the upper part 1022 of the auricle 1020 is further opened to the outside when the inner wall surface 2221aa side of the fixing portion 2221a is engaged with the upper part 1022 of the auricle 1020. That is, the end 2221c (the end on the opposite side to the fixing portion 2221a) side of the shielding wall 2221b' is the open portion O51, and further, a part of the shielding wall 2221b' on the fixing portion 2221a side is also the open portion O52 (through hole). The opening portion O52 is provided at a position where a part of the upper part 1022 of the auricle 1020 is opened to the outside. The rest is the same as the wearing method 8. Since the shielding wall 2221b' only covers a part of the auricle 1020 (a part of the lower part 1024 side and the upper part 1022 side of the auricle 1020 are not blocked), the external sound is not completely blocked, and the user can also hear the external sound.

[0416] <Wearing method 10>

[0417] like Fig.65 , Fig.66A , Fig.66B as well as Fig.66C As illustrated in the figure, when the shell 2112 is the shell 12, 12", 22 illustrated in the first to fourth embodiments and their modified examples, the sound holes 121a, 221a (first sound holes) of the shell 12, 12", 22 are preferably arranged on the inner side of the shielding wall 2221b, and the sound holes 123a, 223a (second sound holes) are arranged on the outer side of the shielding wall 2221b. Thus, it is possible to suppress the acoustic signal AC1 from being offset by the acoustic signal AC2 on the inner side of the shielding wall 2221b, and to offset a portion of the acoustic signal AC1 (first acoustic signal) leaking to the outer side of the shielding wall 2221b by a portion of the acoustic signal AC2 emitted from the sound holes 123a, 223a (second sound holes). As a result, it is possible to effectively suppress the leakage of the acoustic signal AC1 to the outside without greatly reducing the user's listening efficiency of the acoustic signal AC1.

[0418] In this case, the sound pressure of the acoustic signal AC1 leaking to the outside from the openings O51 and O52 of the shielding walls 2221b and 2221b' is greater than the sound pressure of the acoustic signal AC1 leaking to the outside from the shielding walls 2221b and 2221b' other than the openings O51 and O52. Therefore, the opening area per unit area of ​​the sound holes 123a and 223a (second sound holes) arranged on the side where the openings O51 and O52 are provided is preferably greater than the opening area per unit area of ​​the sound holes 123a and 223a (second sound holes) arranged on the side where the openings O51 and O52 are not provided. As a result, the distribution of the sound pressure of the acoustic signal AC2 (second acoustic signal) released from the sound holes 123a and 223a (second sound holes) can be made close to the distribution of the sound pressure of the acoustic signal AC1 leaking to the outside of the shielding wall 2221b, and the acoustic signal AC1 can be appropriately offset by the acoustic signal AC2. That is, the sound signal AC1 (first sound signal) is emitted from the sound holes 121a and 221a (first sound holes), and the sound signal AC2 (second sound signal) is emitted from the sound holes 123a and 223a (second sound holes). The distribution of the sound pressure can be balanced so that the attenuation rate η of the sound signal AC1 (first sound signal) at the position P2 (second point) based on the position P1 (first point) in this case is 11 The attenuation rate η of the acoustic signal due to air propagation at position P2 (second position) based on position P1 (first position) is smaller than that at position P2 (second position). 21 The predetermined value η th Alternatively, the balance of the sound pressure distribution can be achieved so that the attenuation amount η of the acoustic signal AC1 (first acoustic signal) at the position P2 (second position) based on the position P1 (first position) in this case is 12The attenuation η of the acoustic signal caused by air propagation at position P2 (second position) based on position P1 (first position) is greater than 22 The predetermined value ω th Above. In addition, the position P1 (first position) here is a predetermined position where the sound signal AC1 (first sound signal) emitted from the sound hole 221a (first sound hole) reaches. In addition, the position P2 (second position) here is a predetermined position farther from the sound signal output device than the position P1 (first position). Thus, sound leakage can be effectively suppressed.

[0419] The following describes an example in which the shell 2112 is the shell 12 of the first embodiment or its modified example, and the shell 12 (shell 2112) is held on the wearing portion 2221 of the wearing method 8. However, this does not limit the present invention. The shell 2112 may also be the shell 12, 12", 22 illustrated in the second to fourth embodiments and their modified examples, and the shell 12, 12", 22 may also be held on the wearing portion 2221' of the wearing method 9. In this case, the following structure can also be applied.

[0420] like Fig.66B As shown in the example, the sound signal output device 2600 in this case has a driving unit 11 that emits a sound signal AC1 (first sound signal) to one side (the D1 direction side) and emits a sound signal AC2 (second sound signal) that is an inverted signal of the sound signal AC1 (first sound signal) or a signal similar to the inverted signal to the other side (the D2 direction side). As described above, the walls 121 and 123 of the housing 12 are provided with a single or multiple sound holes 121a (first sound holes) for outputting the sound signal AC1 (first sound signal) emitted from the driving unit 11 to the outside, and a single or multiple sound holes 123a (second sound holes) for outputting the sound signal AC2 (second sound signal) emitted from the driving unit 11 to the outside. Fig.66B as well as Fig.66C As described above, part of the acoustic signal AC2 (second acoustic signal) emitted from the sound hole 123a (second sound hole) cancels part of the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole), thereby suppressing sound leakage. Fig.66BAs shown in the example, the sound hole 121a (first sound hole) of the housing 12 is arranged on the inner side (D1 direction side) of the shielding wall 2221b, and the sound hole 123a (second sound hole) is arranged on the outer side (D2 direction side) of the shielding wall 2221b. As a result, it is possible to suppress the acoustic signal AC1 from being offset by the acoustic signal AC2 on the inner side of the shielding wall 2221b, and to offset a part of the acoustic signal AC1 (first acoustic signal) leaking to the outer side of the shielding wall 2221b by a part of the acoustic signal AC2 released from the sound hole 123a (second sound hole). As a result, it is possible to effectively suppress the leakage of the acoustic signal AC1 to the outside without greatly reducing the user's listening efficiency of the acoustic signal AC1.

[0421] As described above, an opening portion O51 is provided at a portion of the shielding wall 2221b (end portion 2221c side), and when the upper portion 1022 of the auricle 1020 is engaged with the inner wall surface 2221aa side of the fixing portion 2221a, the opening portion O51 partially opens the portion of the auricle 1020 (lower portion 1024) to the outside ( Fig.66A as well as Fig.66B That is, the opening portion O51 of this example is provided at a position where the lower portion 1024 of the auricle 1020 is opened to the outside when the upper portion 1022 of the auricle 1020 is fitted with the inner wall surface 2221aa of the fixing portion 2221a. Here, the opening area per unit area of ​​the sound hole 123a (second sound hole) arranged on the side where the opening portion O51 is provided ( Fig.66B ) is larger than the opening area per unit area of ​​the sound hole 123a (second sound hole) arranged on the side where the opening portion is not provided ( Fig.66C ). That is, Fig.66B , Fig.66C , Fig.67AAs shown in the example, the sound hole 123a (second sound hole) is provided along the aforementioned circumference C1. Here, it is assumed that the surface of the wall portion 123 of the shell 12 is equally divided into unit area regions (in this example, unit area regions C5-1 and C5-2) along the circumference C1. In this example, the number of sound holes 123a (second sound holes) arranged on the side where the opening portion O51 is provided (unit area region C5-1) is greater than the number of sound holes 123a (second sound holes) arranged on the side where the opening portion O51 is not provided (unit area region C5-2). Therefore, the opening area per unit area of ​​the sound holes 123a (second sound holes) arranged on the side where the opening portion O51 is provided (unit area region C5-1) is greater than the opening area per unit area of ​​the sound holes 123a (second sound holes) arranged on the side where the opening portion O51 is not provided (unit area region C5-2). Thus, the sound pressure distribution of the sound signal AC2 (second sound signal) emitted from the sound holes 123a, 223a (second sound holes) can be made close to the sound pressure distribution of the sound signal AC1 leaking to the outside of the shielding wall 2221b, and the sound signal AC1 can be appropriately offset by the sound signal AC2, thereby effectively suppressing sound leakage.

[0422] In addition, if Fig.67B As shown in the example, the average opening area of ​​the sound hole 123a (second sound hole) arranged on the side with the opening portion O51 (unit area region C5-1) may be larger than the average opening area of ​​the sound hole 123a (second sound hole) arranged on the side without the opening portion (unit area region C5-2). Fig.68A As shown in the example, two sound holes 123a (second sound holes) may be arranged at equal intervals in the direction orthogonal to the circumference C1 on the side (unit area C5-1) where the opening portion O51 is provided, and one sound hole 123a (second sound hole) may be arranged at equal intervals in the direction of the circumference C1 on the side (unit area C5-2) where no opening portion is provided. Or, Fig.68B As shown in the example, the sound hole 123a (second sound hole) may be arranged on the side (unit area region C5-1) where the opening portion O51 is provided, but the sound hole 123a (second sound hole) may not be arranged on the side (unit area region C5-2) where the opening portion is not provided. In this way, sound leakage can also be effectively suppressed.

[0423] [Sixth Embodiment]

[0424] In the sixth embodiment, another wearing method of the ear-worn type sound signal output device is exemplified.

[0425] <Wearing Style 11>

[0426] like Fig.69AAs in the acoustic signal output device 3100 illustrated in FIG. 1 , the configuration may be such that the wearing portion 2121 of the acoustic signal output device 2100 in the wearing mode 1 is omitted.

[0427] <Wearing method 12>

[0428] like Fig.69B As in the example of the sound signal output device 3200 shown in the figure, the wearing portion 2123 of the sound signal output device 2100 of the wearing mode 1 may be omitted, and the shell 2112 may be any one of the aforementioned shells 12, 12", 22. However, in this example, the structure is such that when the sound signal output device 3200 is worn on the auricle 1020, the opening direction (D1) of the sound holes 121a, 221a of the shells 12, 12", 22 is approximately perpendicular to the direction of the external auditory canal 1021.

[0429] <Wearing method 13>

[0430] like Fig.70A As in the example of the sound signal output device 3300 shown in the figure, the wearing portion 2121 of the sound signal output device 2300 of the wearing mode 5 may be omitted, and the shell 2112 may be any one of the aforementioned shells 12, 12", 22. In this example, when the sound signal output device 3300 is worn on the auricle 1020, the sound holes 121a, 221a of the shells 12, 12", 22 face the external auditory canal 1021 side.

[0431] <Wearing method 14>

[0432] like Fig.70B As in the example of the sound signal output device 3600 shown in FIG. 1 , the sound signal output device 2500 of the wearing mode 8 may be replaced with the wearing portion 2221′. The wearing portion 2221′ includes a shielding wall 2221b configured to cover only the upper portion 1022 of the auricle 1020 when the inner wall surface side of the fixing portion 2221a is engaged with the upper portion 1022 of the auricle 1020. In addition, the end 2221c′ of the shielding wall 2221b is configured to be curved, and the area covered by the shielding wall 2221b on the helix 1022a side of the auricle 1020 is smaller than the area covered by the shielding wall 2221b on the root side of the auricle 1020.

[0433] <Wearing method 15>

[0434] like Fig.71A As in the acoustic signal output device 4100 illustrated in FIG. 1 , the wearing portion 2122 of the acoustic signal output device 2200 of the wearing mode 4 may be omitted.

[0435] <Wearing method 16>

[0436] like Fig.71B 2 , the structure may be as follows: the wearing part 2122 of the sound signal output device 2200 of the wearing mode 4 is omitted, and a wearing part 4421 configured to contact the concha cavity 1025 of the auricle 1020 when worn is further provided. One end of the wearing part 4421 holds the housing 2112, and the other end of the wearing part 4421 is configured to support the concha cavity 1025 in a manner not to block the external auditory canal. In this way, more stable wearing can be achieved.

[0437] <Wearing method 17>

[0438] Fig.72A The audio signal output device 4200 illustrated in the example comprises: a shell 2112; a columnar wearing portion 4210, which holds the shell 2112 and is configured to be arranged on the root side of the auricle 1020 when worn; and an arc-shaped wearing portion 4220, which is held at both ends of the wearing portion 4210 and is worn in the area from the back side of the upper part 1022 of the auricle 1020 to the lower part 1024.

[0439] <Wearing method 18>

[0440] like Fig.72B As in the example of the sound signal output device 4300 shown in the figure, the wearing portion 2122 of the sound signal output device 2200 of the wearing mode 4 may be omitted, and the shell 2112 may be any one of the aforementioned shells 12, 12", 22. However, in this example, the structure is such that when the sound signal output device 4300 is worn on the auricle 1020, the opening direction (D1) of the sound holes 121a, 221a of the shells 12, 12", 22 is approximately perpendicular to the direction of the external auditory canal 1021.

[0441] <Wearing method 19>

[0442] FIG. 73A to FIG. 73E The sound signal output device 5110 of the wearing method 19 illustrated in the figure has a housing 5111 for emitting sound signals and a wearing part 5112 of a type that holds the housing 5111 and is hooked on the back side of the upper part 1022 of the auricle 1020 when worn. The wearing part 5112 is a curved rod-shaped member, and the housing 5111 is mounted on one end thereof in a manner that allows rotation in the R5 direction. Fig.73EAs shown in the example, the housing 5111 is worn in a state where the sound hole for emitting the sound signal faces the external auditory canal without blocking the external auditory canal. At this time, the auricle 1020 is sandwiched between the housing 5111 and the wearing portion 5112, so that the sound signal output device 5110 is fixed to the auricle 1020. In addition, since the housing 5111 can rotate in the R5 direction relative to one end of the wearing portion 5112, the wearing position and the position of the sound hole can be adjusted to match the size and shape of each auricle 1020.

[0443] <Wearing method 20>

[0444] FIG. 74A to FIG. 74C The sound signal output device 5120 of the wearing method 20 illustrated in FIG. 1 includes a housing 5121 for emitting sound signals, and a wearing portion 5122 of a type that holds the housing 5121 and is hooked on the back side of the upper portion 1022 of the auricle 1020 when worn. Unlike the wearing method 19, the housing 5121 cannot rotate relative to the wearing portion 5122. Fig.74C As shown in the example, the housing 5121 is worn without blocking the external auditory canal and with the sound hole for emitting the sound signal facing the external auditory canal. At this time, the auricle 1020 is sandwiched between the housing 5121 and the wearing part 5122, so that the sound signal output device 5120 is fixed to the auricle 1020.

[0445] <Wearing method 21>

[0446] Fig.75A as well as Fig.75B The sound signal output devices 5130 and 5140 of the wearing method 21 illustrated in the example have housings 5131 and 5141 for emitting sound signals, and wearing parts 5132 and 5142 of the type that hold the housings 5131 and 5141 and are hooked on the back side of the upper part 1022 of the auricle 1020 when worn. Fig.75B The acoustic signal output device 5140 illustrated in FIG. 1 is provided with a wearing portion 5143 configured to be in contact with the concha cavity 1025 of the auricle 1020 when worn. This enables more stable wearing.

[0447] <Wearing method 22>

[0448] Fig.76A , Fig.76B , Fig.76CThe audio signal output device 5150 illustrated in the example comprises: a housing 5151 for emitting an audio signal; a rod-shaped wearing portion 5152 for holding the housing 5151 and being of a type that is hooked on the back side of the upper portion 1022 of the auricle 1020 when worn; a columnar supporting portion 5154 for holding the housing 5151 at one end and holding the wearing portion 5152 at the other end; a rod-shaped wearing portion 5153 for being of a type that is hooked on the back side of the middle portion 1023 and the upper portion 1022 from the middle portion 1023 side of the auricle 102 when worn; and a columnar supporting portion 5155 for holding the housing 5151 at one end and holding the wearing portion 5153 at the other end. Fig.76C As shown in the example, the housing 5151 is worn without blocking the external auditory canal and with the sound hole for emitting the sound signal facing the external auditory canal. At this time, the auricle 1020 is sandwiched between the housing 5151 and the wearing parts 5152 and 5153, so that the sound signal output device 5150 is fixed to the auricle 1020.

[0449] <Wearing method 23>

[0450] Figures 77A to 77E The sound signal output device 5160 illustrated in the example comprises: a housing 5161 for emitting a sound signal; a columnar wearing portion 5164 for holding the housing 5161 and configured to be arranged at the root side of the auricle 1020 when worn; a rod-shaped wearing portion 5162 held at one end of the wearing portion 5164 and hooked on the back side of the upper portion 1022 of the auricle 1020 when worn; and a rod-shaped wearing portion 5163 held at the other end of the wearing portion 5164 and hooked on the back side of the lower portion 1024 of the auricle 1020 when worn. Fig.77E As shown in the example, the housing 5161 is worn without blocking the external auditory canal and with the sound hole for emitting the sound signal facing the external auditory canal. At this time, the auricle 1020 is sandwiched between the housing 5161 and the wearing portion 5164 and the wearing portions 5152 and 5153, thereby fixing the sound signal output device 5160 to the auricle 1020.

[0451] <Wearing method 24>

[0452] FIG. 78A to FIG. 78D as well as FIG. 79A to FIG. 79D The sound signal output devices 5170 and 5180 illustrated in the example respectively include: a housing 5171 and 5181 for emitting sound signals; a columnar wearing portion 5172 and 5182 configured to be arranged on the back side of the middle portion 1023 of the auricle 102 when worn; and a curved belt-shaped supporting portion 5173 and 5183, one end of which holds the housing 5171 and 5181 and the other end of which holds the wearing portion 5172 and 5182. Fig.78D as well as Fig.79DAs shown in the example, the shells 5171 and 5181 are worn without blocking the external auditory canal and with the sound hole for emitting the sound signal facing the external auditory canal. At this time, the auricle 1020 is sandwiched between the shells 5171 and 5181 and the wearing parts 5172 and 5182, so that the sound signal output devices 5170 and 5180 are fixed to the auricle 1020.

[0453] <Wearing method 25>

[0454] FIG. 80A to FIG. 80C The sound signal output device 5190 illustrated in the example has a housing 5191 for emitting sound signals, and a rod-shaped wearing portion 5192 that holds the housing 5191 and is configured to be arranged on the back side of the auricle 102 when worn. The wearing portion 5192 holds the housing 5191 at one end on the side of the lower part 1024 of the auricle 1020 when worn. Fig.80C As shown in the example, the housing 5191 is worn without blocking the external auditory canal and with the sound hole for emitting the sound signal facing the external auditory canal. At this time, the auricle 1020 is sandwiched between the housing 5191 and the wearing part 5192, so that the sound signal output device 5190 is fixed to the auricle 1020.

[0455] <Wearing method 26>

[0456] Figures 81A to 81E The sound signal output device 5200 illustrated in FIG. 5 includes a housing 5201 for emitting sound signals, and a ring-shaped wearing portion 5202 for holding the housing 5201. Fig.81E As shown in the example, the housing 5201 is worn in a state where the sound hole for emitting the sound signal faces the external auditory canal without blocking the external auditory canal. When worn, the auricle 1020 is inserted into the annular wearing portion 5202, and the wearing portion 5202 is arranged on the back side of the upper part 1022, the middle part 1023, and the lower part 1024 of the auricle 1020. At this time, the auricle 1020 is sandwiched between the housing 5201 and the wearing portion 5202, and thus the sound signal output device 5200 is fixed to the auricle 1020.

[0457] <Wearing method 27>

[0458] like Fig.82A as well as Fig.84B As illustrated in the figure, the sound signal output device may be a type in which any of the housings 12, 12", and 22 illustrated in the first to fourth embodiments and their modified examples are fixed to the temple (temple).

[0459] exist Fig.82A as well as Fig.82BIn the audio signal output devices 5310 and 5320 illustrated in the example, one end of the support portion 5312 is held at the middle portion of the temple 5311, and the other end of the support portion 5312 holds the housing 12. In any of the audio signal output devices 5310 and 5320, the temple 5311 is disposed on the back side of the upper portion 1022 of the auricle 1020 when worn. Fig.82A In the acoustic signal output device 5310 illustrated in FIG. 1 , the opening direction of the sound hole 121a of the housing 12 is arranged to be inclined relative to the external auditory canal 1021 when worn. Fig.82B In the example of the sound signal output device 5320 illustrated in FIG, the sound hole 121a of the housing 12 is arranged to face the external auditory canal 1021 side when worn.

[0460] exist Fig.83A as well as Fig.83B In the audio signal output devices 5340 and 5350 illustrated in the example, the housing 12 is directly held at the middle portion of the temple 5311. In any of the audio signal output devices 5340 and 5350, the temple 5311 is arranged on the back side of the upper portion 1022 of the auricle 1020 when worn. Fig.83A In the audio signal output device 5340 illustrated in the example, the housing 12 is held on the temple 5311 in such a manner that the opening direction of the sound hole 121a of the housing 12 is substantially perpendicular to the temple 5311, and is configured so that the opening direction of the sound hole 121a of the housing 12 is substantially perpendicular to the external auditory canal 1021 when worn. Fig.83B In the audio signal output device 5350 illustrated in the example, the shell 12 is held on the temple 5311 in a manner such that the opening direction of the sound hole 121a of the shell 12 is approximately parallel to the temple 5311, and is configured such that the opening direction of the sound hole 121a of the shell 12 is toward the upper part 1022 of the auricle 1020 when worn.

[0461] Fig.84A as well as Fig.84B The acoustic signal output devices 5360 and 5370 illustrated in the examples directly hold the housing 12 at the tip portions of the temples 5361 and 5371. In any of the acoustic signal output devices 5360 and 5370, the temples 5361 are arranged on the back side of the upper portion 1022 of the auricle 1020 when worn. Fig.84A In the audio signal output device 5360 illustrated in the example, the sound hole 121a of the housing 12 is configured so that the opening direction is from the root side of the lower part 1024 of the auricle 1020 to the external auditory canal 10 side when worn. Fig.84BIn the audio signal output device 5370 illustrated in the example, the sound hole 121a of the housing 12 is configured so that the opening direction is from the outside of the lower part 1024 of the auricle 1020 toward the external auditory canal 10 side when worn.

[0462] <Wearing method 28>

[0463] In addition, if Fig.85A As in the example of the sound signal output device 5380 illustrated in FIG. 1 , any one of the housings 12, 12″, 22 illustrated in the first to fourth embodiments and their modified examples may be fixed to a rod-shaped wearing portion 5381 bent into a shape worn on the neck or shoulder of the user 1000. In addition, as Fig.85B As in the example of the sound signal output device 5390 shown in FIG. 1 , any one of the housings 12, 12″, and 22 may be fixed to a rod-shaped wearing portion 5391 bent into a shape worn on the top of the head of the user 1000. Fig.85C As in the acoustic signal output device 5400 illustrated in the example, any one of the housings 12, 12", and 22 may be fixed to a rod-shaped wearing portion 5401 that is bent into a shape to be worn on the back of the user's head and the auricle 1020.

[0464] <Other wearing methods>

[0465] In addition, the wearing method of the existing open-type headphones can also be applied to the sound signal output devices 4, 4', 10, 20, 30 illustrated in the first to fourth embodiments and their modified examples. For example, as illustrated in reference 1 (https: / / www.sony.jp / headphone / products / STH40D / feature_1.html), a ring body serving as a stopper can be added to the D1 direction side of the housing 12, 12", 22 or the sound signal output unit 40-1, 40-2, and a U-shaped wearing portion can be added to the housing 12, 12", 22 or the sound signal output unit 40-1, 40-2 on the opposite side of the D1 direction. In this case, the annular body is placed against the peripheral portion of the external auditory canal (for example, the concha), and the lower part of the auricle is clamped by the U-shaped wearing portion, so that the shell 12, 12", 22 or the sound signal output portion 40-1, 40-2 is worn on the auricle. In particular, when the wearing method of reference 1 is applied to the sound signal output device 20 of the second embodiment, the following structure is sufficient: a annular body serving as a stopper is added to the D1 direction side of the shell 22, and the U-shaped wearing portion added to the D2 direction side of the shell 22 also serves as the waveguide 24, 25 and the shell 23 ( Fig.40 ).

[0466] For example, as illustrated in reference 2 (https: / / www.bose.com / en_us / products / headphones / earbuds / sport-open-earbuds.html#v=sport_open_earbuds_black), the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 can also be set to a roughly elliptical column shape, and a J-shaped wearing portion is provided on the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2. In this case, the D1 direction side of the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 is placed against the surface side (external auditory hole side) of the upper part of the auricle, and the J-shaped wearing portion is hooked on the back side of the upper part of the auricle, so that the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 is worn on the auricle.

[0467] For example, as illustrated in reference 3 (https: / / ambie.co.jp / soundearcuffs / tws / ), the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 may be configured to be roughly spherical, and the opposite side of the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 in the D1 direction is held by one end side of a C-shaped wearing portion. The other end of the C-shaped wearing portion may also be configured to be roughly spherical. In this case, the D1 direction side of the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 is placed against the peripheral portion of the external auditory hole (for example, the concha), and the middle portion of the auricle is grasped (clamped) by the C-shaped wearing portion, so that the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 is worn on the auricle.

[0468] For example, as illustrated in reference 4 (https: / / www.jabra.jp / bluetooth-headsets / jabra-elite-active-45e##100-99040000-40), a sound channel tube for directing the sound signal emitted from the sound holes 121a, 221a toward the external auditory canal may be added to the sound holes 121a, 221a of the housing 12, 12," 22 or the sound signal output units 40-1, 40-2.

[0469] For example, as illustrated in reference 5 (https: / / www.audio-technica.co.jp / product / ATH-EW9), a semicircular wearing portion (ear hanger) may be provided, which has an adjustment mechanism (slide fit) for adjusting the position of the housing 12, 12", 22 or the audio signal output portion 40-1, 40-2 relative to the auricle. In this case, the D1 direction side of the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 is placed against the front side of the upper part of the auricle, and the semicircular wearing portion is hooked on the back side of the upper part of the auricle, so that the shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 is worn on the auricle. By operating the adjustment mechanism in this state, the position of the worn shell 12, 12", 22 or the sound signal output unit 40-1, 40-2 relative to the auricle can be adjusted.

[0470] For example, as illustrated in reference 6 (https: / / www.mu6.live / ), a headband-type wearing portion may be provided on the shell 12, 12", 22 or the sound signal output portion 40-1, 40-2. For example, the shell 12, 12", 22 or the sound signal output portion 40-1, 40-2 may be held at both ends of the headband-type wearing portion. At this time, the shell 12, 12", 22 or the sound signal output portion 40-1, 40-2 may also be able to rotate relative to both ends of the headband-type wearing portion, respectively. In this case, the D1 direction side of the shell 12, 12", 22 or the sound signal output portion 40-1, 40-2 is placed against the auricle or near the auricle, and the headband-type wearing portion is worn on the head. At this time, by rotating the shell 12, 12", 22 or the audio signal output unit 40-1, 40-2 relative to the headband-type wearing part, the wearing position of the headband-type wearing part and the position of the shell 12, 12", 22 or the audio signal output unit 40-1, 40-2 relative to the auricle can be adjusted.

[0471] [Other modifications, etc.]

[0472] In addition, the present invention is not limited to the above-mentioned embodiments. For example, in the above-mentioned embodiments and their variations, examples are shown in which the present invention is applied to an audio listening device that is worn on the ear without sealing the external auditory canal of the user (for example, open earphones, headphones, etc.). However, this does not limit the present invention, and the present invention can also be applied to an audio listening device that is worn on a body part other than the ear without sealing the external auditory canal of the user, such as a bone conduction earphone and a neck speaker earphone.

[0473] Furthermore, for example, the present invention can also be used as a sound signal output device as follows: even if a sound-absorbing material is not provided at the sound hole through which the sound signal emitted from the driving unit passes, the attenuation rate of the sound signal emitted to the outside can be controlled. Furthermore, for example, the present invention can also be used as a sound signal output device as follows: even if directional control based on physical shape or signal processing is not performed, the sound signal emitted from the driving unit can be attenuated to the point where it cannot be heard at a specified position. Furthermore, for example, the present invention can also be used as a sound signal output device as follows: even if a speaker is not provided at the location where the sound signal is to be attenuated, the sound signal at that location can be attenuated. Furthermore, for example, the present invention can also be used as a sound signal output device as follows: even if the periphery of a specific local area is not covered by a sound-absorbing material, the sound signal in the local area can be played locally.

[0474] Description of Reference Numerals

[0475] 4, 4', 10, 20, 30, 2100-2600, 3100-3300, 3600, 4100-4300, 5110-5200, 5310-5400 sound signal output device

[0476] 11 drive units

[0477] 113 vibration plate

[0478] 12, 12", 22, 23, 2112, 5021, 5111, 5121, 5131, 5151, 5161, 5171, 5191, 5201 housing

[0479] 121a, 123a, 221a, 223a sound holes

[0480] 13Sound-absorbing materials

[0481] 24, 25 waveguide

[0482] 31, 41 circuit department

[0483] 40-1, 40-2 Sound signal output unit

[0484] AC1, AC2 audio signal

[0485] AR21, AR22 hollow part

[0486] C1 Circumference

[0487] C1-1, C1-2, C1-3, C1-4 unit arc area

[0488] MAC1, MAC2 mono audio signal

[0489] 2121, 2122, 2123, 2124, 2221, 2224, 4210, 4220, 4421, 5112, 5122, 5132, 5152, 5153, 5162, 5163, 5164, 5172, 5192, 5202, 5381, 5391, 5401 wearing part

[0490] 2121a, 2122a, 2123a, 2124a, 2221a fixed part

[0491] 2221b shielding wall.

Claims

1. An audio signal output device, comprising: a drive unit; and a housing, accommodating the drive unit internally, the sound signal emitted from the driving unit to one side is regarded as a first sound signal, and the sound signal emitted from the driving unit to the other side is regarded as a second sound signal, A single or multiple first sound holes for exporting the first sound signal to the outside, and a single or multiple second sound holes for exporting the second sound signal to the outside are provided on the wall of the housing. A vibrating body having a resonance frequency belonging to a predetermined frequency band within the audible frequency band is provided in the housing so as to be arranged on a path of the second acoustic signal. The sound signal output device is designed so that, when the first sound signal is emitted from the first sound hole and the second sound signal is emitted from the second sound hole, an attenuation rate of the first sound signal at a second location farther from the sound signal output device than the first location with respect to a predetermined first location at which the first sound signal arrives becomes less than a predetermined value or less than an attenuation rate due to air propagation of the sound signal at the second location with respect to the first location, or The acoustic signal output device is designed so that the attenuation of the first acoustic signal at the second point based on the first point becomes greater than a predetermined value or more than the attenuation of the acoustic signal due to air propagation at the second point based on the first point.

2. The sound signal output device according to claim 1, wherein: For the vibrating body, The sound pressure level at the second location when the first sound signal is emitted from the first sound hole and the second sound signal is emitted from the second sound hole is lower than the sound pressure level at the second location when the first sound signal is emitted from the first sound hole but the second sound signal is not emitted from the second sound hole, and / or The sound pressure level at the second location when the first sound signal is emitted from the first sound hole and the second sound signal is emitted from the second sound hole is lower than the sound pressure level at the second location when the first sound signal is not emitted from the first sound hole and the second sound signal is emitted from the second sound hole.

3. The sound signal output device according to claim 1, wherein: ω is the frequency, H neg,in (ω) is a transfer function from the other side of the driving unit in the internal space of the housing to a release position of the second acoustic signal to the outside of the acoustic signal output device, H pos,out (ω) is a transfer function from the release position of the first acoustic signal to the outside of the acoustic signal output device to the second point, H neg,out (ω) is a transfer function from the emission position of the second acoustic signal to the outside of the acoustic signal output device to the second point, The vibrator is responsive to any frequency ω in the predetermined frequency band. neg,in (ω) and H pos,out (ω) / H neg,out (ω) consistent or approximate.

4. The sound signal output device according to claim 1, wherein: The predetermined frequency band is a band of 3000 Hz to 8000 Hz.

5. The sound signal output device according to claim 1, wherein: The vibrating body is a vibrating membrane.

6. The sound signal output device according to claim 1, wherein: The first sound hole is located at an eccentric position offset from the center of the area of ​​the wall portion disposed on the one side of the driver unit. A person's auditory sensitivity to an acoustic signal having a resonant frequency above a predetermined frequency of the shell when the position of the first sound hole is biased toward the eccentric position is lower than a person's auditory sensitivity to an acoustic signal having a resonant frequency above the predetermined frequency of the shell when the first sound hole is assumed to be provided at a central position in the center of the area of ​​the wall portion disposed on the one side of the drive unit, and / or The sharpness of the peak of the first sound signal emitted from the first sound hole of the shell that is deviated from the position of the first sound hole toward the eccentric position and / or the second sound signal emitted from the second sound hole above the specified frequency is blunter than the sharpness of the peak of the first sound signal emitted from the first sound hole of the shell that is assumed to be set at the central position and / or the second sound signal emitted from the second sound hole above the specified frequency.

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