Audio signal output device

Abstract

Provided is an acoustic signal output device including: a housing that emits an acoustic signal; and a worn section that holds the housing and is configured so as to be worn on the auricle. The worn section includes a fixing section for holding a concave inner wall surface configured so as to be fitted into the upper part of the auricle, and a shielding wall configured so as to cover only part of the auricle when the inner wall surface side of the fixing section is fitted into the upper part of the auricle.

Description

[Technical field]

[0001] The present invention relates to an acoustic signal output device, and more particularly to an ear-worn acoustic signal output device. [Background technology]

[0002] In recent years, the increased burden on the ears caused by ear-worn acoustic signal output devices such as earphones and headphones has become a problem. Under these circumstances, in addition to conventional acoustic signal output devices that block the ear canal when worn, open-ear acoustic signal output devices that do not seal the ear canal are also known as devices that reduce the burden on the ear (see, for example, Non-Patent Document 1, etc.). If such acoustic signal output devices are classified by the wearing method, examples include an insertion type that is worn by inserting an earpiece into the ear canal, an ear-hook type that is worn by hooking an arm around the outer base of the auricle, and a clamping type that is worn by clamping one point of the auricle with an arm. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] “WHAT ARE OPEN-EAR HEADPHONES?”, [online], Bose Corporation, [Retrieved September 13, 2021], Internet<https: / / www.bose.com / en_us / better_with_bose / open-ear-headphones.html> Summary of the Invention [Problem to be solved by the invention]

[0004] However, conventional insert, ear-hook and clip-on types have the problem of placing a heavy burden on the ears. First, with the insertion type, the inserted earpiece may press against the ear canal, causing pain or damage. With the ear-hook type, the arm may press against the outer ear canal, causing pain or damage. With the conventional clamping type, the load is concentrated at one point on the pinched ear canal, causing pain or damage. Furthermore, with the clamping and ear-hook types, the earphones may shift out of position, making it impossible to stably wear them in the desired position.

[0005] The present invention has been made in consideration of the above points, and has an object to provide an ear-mounted acoustic signal output device that places less strain on the ears and can be worn stably. [Means for solving the problem]

[0006] There is provided an acoustic signal output device having a housing that emits an acoustic signal and a mounting part that holds the housing and is configured to be mounted on an auricle, wherein the mounting part includes a fixing part having a concave inner wall surface that is configured to be fitted into an upper part of the auricle, and a shielding wall that is configured to cover only a part of the auricle when the inner wall surface side of the fixing part is fitted into the upper part of the auricle. Effect of the Invention

[0007] Such an acoustic signal output device places less strain on the ears and can be worn stably. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a transparent perspective view illustrating the configuration of an acoustic signal output device according to a first embodiment. [Diagram 2] Fig. 2A is a transparent plan view illustrating the configuration of the acoustic signal output device of the first embodiment, Fig. 2B is a transparent front view illustrating the configuration of the acoustic signal output device of the first embodiment, and Fig. 2C is a bottom view illustrating the configuration of the acoustic signal output device of the first embodiment. [Diagram 3] Figure 3A is an end view 2BA-2BA of Figure 2B, Figure 3B is an end view 2A-2A of Figure 2A, and Figure 3C is an end view 2BC-2BC of Figure 2B. [Figure 4] FIG. 4 is a conceptual diagram illustrating the arrangement of sound holes. [Diagram 5] Fig. 5A is a diagram illustrating a state in which the acoustic signal output device of the first embodiment is used, and Fig. 5B is a diagram illustrating conditions for observing an acoustic signal emitted from the acoustic signal output device of the first embodiment. [Figure 6] FIG. 6 is a graph illustrating the frequency characteristics of an acoustic signal observed at position P1 in FIG. 5B. [Figure 7] FIG. 7 is a graph illustrating the frequency characteristics of an acoustic signal observed at position P2 in FIG. 5B. [Figure 8] FIG. 8 is a graph showing an example of the difference between an acoustic signal observed at a position P1 and an acoustic signal observed at a position P2. [Figure 9] 9A and 9B are graphs illustrating the relationship between the area ratio of the sound holes and sound leakage. [Figure 10] Fig. 10A is a front view illustrating the arrangement of sound holes, and Fig. 10B is a conceptual diagram illustrating the arrangement of sound holes. [Figure 11] Fig. 11A is a front view illustrating the arrangement of sound holes, and Fig. 11B is a conceptual diagram illustrating the arrangement of sound holes. [Figure 12] 12A to 12C are front views illustrating modified examples of the arrangement of sound holes. [Figure 13] 13A and 13B are transparent plan views illustrating modified examples of the arrangement of sound holes. [Figure 14] 14A and 14B are conceptual diagrams illustrating modified examples of the arrangement of sound holes. [Figure 15] Fig. 15A is a see-through front view illustrating modified examples of the arrangement of sound holes, and Fig. 15B is an end view illustrating modified examples of the arrangement of sound holes and modified examples of the distance between the driver unit and the housing. [Figure 16] 16A to 16C are end views illustrating modified examples of the acoustic signal output device of the first embodiment. [Figure 17]FIG. 17 is a graph comparing the frequency characteristics of the acoustic signal observed at position P1 in FIG. 5B. [Figure 18] FIG. 18 is a graph illustrating the frequency characteristics of the acoustic signal observed at position P2 in FIG. 5B. [Figure 19] FIG. 19 is a graph illustrating an example of the difference between an acoustic signal observed at a position P1 and an acoustic signal observed at a position P2. [Figure 20] FIG. 20 is a see-through perspective view illustrating the configuration of an acoustic signal output device according to the second embodiment. [Figure 21] Fig. 21A is a transparent plan view illustrating the configuration of an acoustic signal output device of a second embodiment, Fig. 21B is a transparent front view illustrating the configuration of an acoustic signal output device of a first embodiment, and Fig. 21C is a bottom view illustrating the configuration of an acoustic signal output device of the first embodiment. [Figure 22] Fig. 22A is an end view taken along line 21A-21A of Fig. 21B. Fig. 22B is a cross-sectional view taken along line 21B-21B of Fig. 21A. [Diagram 23] 23A and 23B are views for illustrating a state in which the acoustic signal output device of the second embodiment is used. [Figure 24] FIG. 24 is a see-through perspective view illustrating a modified example of the acoustic signal output device of the second embodiment. [Diagram 25] Fig. 25A is a transparent plan view illustrating a modified example of the acoustic signal output device of the second embodiment, Fig. 25B is a transparent front view illustrating a modified example of the acoustic signal output device of the second embodiment, and Fig. 25C is a bottom view illustrating a modified example of the acoustic signal output device of the second embodiment. [Figure 26] FIG. 26 is an end view of 25A-25A of FIG. 25B. [Figure 27] FIG. 27 is a perspective view illustrating the configuration of an acoustic signal output device according to the third embodiment. [Figure 28] FIG. 28 is a see-through perspective view illustrating the configuration of an acoustic signal output device according to the third embodiment. [Figure 29] FIG. 29 is a conceptual diagram illustrating the arrangement of sound holes. [Diagram 30]30A to 30C are block diagrams illustrating the configuration of the circuit unit. [Diagram 31] FIG. 31 is a diagram illustrating a usage state of the acoustic signal output device of the third embodiment. [Diagram 32] Fig. 32A is a perspective view illustrating a modified example of an acoustic signal output device of the third embodiment, and Fig. 32B is a conceptual diagram illustrating a modified example of the arrangement of sound holes. [Diagram 33] Fig. 33A is a see-through perspective view illustrating a modified example of the acoustic signal output device of the third embodiment. Fig. 33B is a view illustrating a modified example of the acoustic signal output device of the third embodiment. [Diagram 34] Fig. 34A is a diagram illustrating a configuration of an acoustic signal output device according to a fourth embodiment, and Fig. 34B is a diagram illustrating a modified example of the acoustic signal output device according to the fourth embodiment. [Diagram 35] Fig. 35A is a see-through front view for illustrating the configuration of an acoustic signal output device of the fifth embodiment, Fig. 35B is a see-through plan view for illustrating the configuration of an acoustic signal output device of the fifth embodiment, and Fig. 35C is a see-through right side view for illustrating the configuration of an acoustic signal output device of the fifth embodiment. [Diagram 36] Fig. 36A is a plan view illustrating the fixing part of the fifth embodiment, Fig. 36B is a right side view illustrating the fixing part of the fifth embodiment, Fig. 36C is a front view illustrating the fixing part of the fifth embodiment, and Fig. 36D is a cross-sectional view taken along line 36A-36A of Fig. 36A. [Figure 37] Fig. 37A is a see-through front view illustrating a modified example of the acoustic signal output device of the fifth embodiment, Fig. 37B is a see-through plan view illustrating a modified example of the acoustic signal output device of the fifth embodiment, and Fig. 37C is a see-through right side view illustrating a modified example of the acoustic signal output device of the fifth embodiment. [Figure 38] FIG. 38 is a front view illustrating a modification of the acoustic signal output device of the fifth embodiment. [Figure 39] 39A and 39B are front views illustrating a modification of the acoustic signal output device of the fifth embodiment. [Diagram 40]Fig. 40A is a plan view illustrating a modified example of the acoustic signal output device of the fifth embodiment, and Fig. 40B is a conceptual diagram illustrating a modified example of the arrangement of sound holes. [Diagram 41] Fig. 41A is a plan view illustrating a modified example of the acoustic signal output device of the fifth embodiment, and Fig. 41B is a conceptual diagram illustrating a modified example of the arrangement of sound holes. [Diagram 42] FIG. 42 is a see-through front view for illustrating the configuration of the acoustic signal output device of the fifth embodiment. [Diagram 43] Fig. 43A is a rear view illustrating the configuration of the acoustic signal output device of the fifth embodiment, and Fig. 43B is a cross-sectional view taken along line 43A-43A in Fig. 43A. [Diagram 44] FIG. 44 is a see-through front view illustrating a modified example of the acoustic signal output device of the fifth embodiment. [Diagram 45] FIG. 45 is a see-through front view illustrating a modified example of the acoustic signal output device of the fifth embodiment. [Diagram 46] Fig. 46A is a see-through front view illustrating a modified example of the acoustic signal output device of the fifth embodiment, Fig. 46B is a see-through bottom view illustrating a modified example of the acoustic signal output device of the fifth embodiment, and Fig. 46C is a plan view illustrating a modified example of the acoustic signal output device of the fifth embodiment. [Figure 47] 47A and 47B are conceptual diagrams illustrating modified examples of the arrangement of sound holes. [Figure 48] 48A and 48B are conceptual diagrams illustrating modified examples of the arrangement of sound holes. [Figure 49] Fig. 49A is a front view illustrating a modification of the acoustic signal output device of the sixth embodiment, and Fig. 49B is a perspective view illustrating the modification of the acoustic signal output device of the sixth embodiment. [Figure 50] Fig. 50A is a perspective view illustrating a modification of the acoustic signal output device of the sixth embodiment, and Fig. 50B is a plan view illustrating the modification of the acoustic signal output device of the sixth embodiment. [Figure 51]Fig. 51A is a plan view illustrating a modified example of the acoustic signal output device of the sixth embodiment, and Fig. 51B is a plan view illustrating a modified example of the acoustic signal output device of the sixth embodiment. [Figure 52] Fig. 52A is a plan view illustrating a modified example of the acoustic signal output device of the sixth embodiment, and Fig. 52B is a see-through perspective view illustrating the modified example of the acoustic signal output device of the sixth embodiment. [Figure 53] Fig. 53A is a plan view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 53B is a right side view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 53C is a front view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 53D is a rear view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 53E is a front view illustrating a state in which the modified example of the acoustic signal output device of the sixth embodiment is in use. [Figure 54] Fig. 54A is a perspective view illustrating a modified example of the acoustic signal output device of the sixth embodiment, Fig. 54B is a perspective view illustrating a modified example of the acoustic signal output device of the sixth embodiment, and Fig. 54C is a perspective view illustrating a state in which the modified example of the acoustic signal output device of the sixth embodiment is used. [Figure 55] 55A and 55B are front views illustrating a state in which a modified example of the acoustic signal output device of the sixth embodiment is used. [Figure 56] Fig. 56A is a front view illustrating a modified example of the acoustic signal output device of the sixth embodiment, Fig. 56B is a rear view illustrating the modified example of the acoustic signal output device of the sixth embodiment, and Fig. 56C is a front view illustrating the modified example of the acoustic signal output device of the sixth embodiment in use. [Figure 57]Fig. 57A is a plan view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 57B is a right side view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 57C is a front view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 57D is a rear view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 57E is a front view illustrating a state in which the modified example of the acoustic signal output device of the sixth embodiment is in use. [Figure 58] Fig. 58A is a plan view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 58B is a front view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 58C is a rear view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 58D is a front view illustrating a state in which the modified example of the acoustic signal output device of the sixth embodiment is used. [Figure 59] Fig. 59A is a plan view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 59B is a front view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 59C is a rear view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 59D is a front view illustrating a state in which the modified example of the acoustic signal output device of the sixth embodiment is used. [Figure 60] Fig. 60A is a left side view illustrating a modified example of the acoustic signal output device of the sixth embodiment, Fig. 60B is a front view illustrating a modified example of the acoustic signal output device of the sixth embodiment, and Fig. 60C is a front view illustrating a state in which the modified example of the acoustic signal output device of the sixth embodiment is used. [Figure 61] Fig. 61A is a plan view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 61B is a right side view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 61C is a front view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 61D is a rear view illustrating a modified example of the acoustic signal output device of the sixth embodiment. Fig. 61E is a front view illustrating a state in which the modified example of the acoustic signal output device of the sixth embodiment is in use. [Figure 62]62A and 62B are conceptual diagrams illustrating a modification of the acoustic signal output device of the sixth embodiment. [Figure 63] 63A and 63B are conceptual diagrams illustrating a modification of the acoustic signal output device of the sixth embodiment. [Figure 64] 64A and 64B are conceptual diagrams illustrating a modification of the acoustic signal output device of the sixth embodiment. [Figure 65] 65A to 65C are conceptual diagrams illustrating modified examples of the acoustic signal output device of the sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, a basic configuration of an audio signal output device will be illustrated, and then a wearing method of the audio signal output device that puts less strain on the ears and allows stable wearing will be illustrated. [First embodiment] First, a first embodiment of the present invention will be described. <Configuration> The acoustic signal output device 10 of this embodiment is a device for listening to sound (for example, open-ear type earphones, headphones, etc.) that is worn without sealing the ear canal of the user. As illustrated in Fig. 1, Fig. 2A to Fig. 2C, and Fig. 3A to Fig. 3C, the acoustic signal output device 10 of this embodiment has a driver unit 11 that converts an output signal (electrical signal representing an acoustic signal) output from a playback device into an acoustic signal and outputs the acoustic signal, and a housing 12 that houses the driver unit 11 inside.

[0010] <Driver unit 11> The driver unit (speaker driver unit) 11 is a device (device having a speaker function) that emits (emits sound) 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) that is an inverse phase signal (phase inversion signal) of the acoustic signal AC1 or an approximation signal of the inverse phase signal to the other side (D2 direction side). That is, the acoustic signal emitted from the driver unit 11 to one side (D1 direction side) is called the acoustic signal AC1 (first acoustic signal), and the acoustic signal emitted from the driver unit 11 to the other side (D2 direction side) is called the acoustic signal AC2 (second acoustic signal). For example, the driver unit 11 includes a diaphragm 113 that emits the acoustic signal AC1 from one surface 113a in the D1 direction by vibration and emits the acoustic signal AC2 from the other surface 113b in the D2 direction by this vibration (FIG. 2B). In this example, the driver unit 11 emits an acoustic signal AC1 from one surface 111 in the direction D1 by vibrating the diaphragm 113 based on an input output signal, and emits an acoustic signal AC2, which is an inverse phase signal of the acoustic signal AC1 or an approximation of the inverse phase signal, from the other surface 111. surface112 toward the D2 direction. That is, the acoustic signal AC2 is emitted secondarily in association with the emission of the acoustic signal AC1. Note that the D2 direction (other side) is, for example, the opposite direction to the D1 direction (one side), but the D2 direction does not need to be strictly the opposite direction to the D1 direction, as long as the D2 direction is different from the D1 direction. The relationship between the one side (D1 direction) and the other side (D2 direction) depends on the type and shape of the driver unit 11. Also, depending on the type and shape of the driver unit 11, the acoustic signal AC2 may be a signal that is strictly the opposite phase of the acoustic signal AC1, or the acoustic signal AC2 may be an approximation of the opposite phase signal of the acoustic signal AC1. For example, the approximation signal of the opposite phase signal of the acoustic signal AC1 may be (1) a signal obtained by shifting the phase of the opposite phase signal of the acoustic signal AC1, (2) a signal obtained by changing (amplifying or attenuating) the amplitude of the opposite phase signal of the acoustic signal AC1, or (3) a signal obtained by shifting the phase of the opposite phase signal of the acoustic signal AC1 and further changing the amplitude. The phase difference between the opposite phase signal of the acoustic signal AC1 and its approximation signal is desirably δ1% or less of one period of the opposite phase signal of the acoustic signal AC1. Examples of δ1% are 1%, 3%, 5%, 10%, 20%, etc. Also, the difference between the amplitude of the opposite phase signal of the acoustic signal AC1 and the amplitude of its approximation signal is desirably δ2% or less of the amplitude of the opposite phase signal of the acoustic signal AC1. Examples of δ2% are 1%, 3%, 5%, 10%, 20%, etc. The type of the driver unit 11 can be exemplified by a dynamic type, a balanced armature chair type, a hybrid type of a dynamic type and a balanced armature type, a condenser type, etc. In addition, there is no limitation on the shapes of driver unit 11 and diaphragm 113. In this embodiment, for the sake of simplicity of explanation, an example is shown in which driver unit 11 has an outer shape of a substantially cylindrical shape having both end faces, and diaphragm 113 has an outer shape of a substantially disc shape, but this does not limit the present invention. For example, driver unit 11 may have an outer shape of a rectangular parallelepiped, and diaphragm 113 may have a dome shape. Examples of the acoustic signal include music, voice, sound effects, and environmental sounds.

[0011] <Case 12> The housing 12 is a hollow member having a wall on the outside, and houses the driver unit 11 inside. For example, the driver unit 11 is fixed to the end of the housing 12 on the D1 direction side. However, this does not limit the present invention. There is no limitation on the shape of the housing 12, but for example, it is desirable that the shape of the housing 12 is rotationally symmetric (line symmetric) or approximately rotationally symmetric about the axis A1 extending along the D1 direction. This makes it easy to provide a sound hole 123a (described in detail later) so that the variation in the energy of the sound emitted from the housing 12 for each direction is reduced. As a result, it becomes easy to reduce sound leakage uniformly in each direction. For example, the housing 12 has a first end face which is a wall portion 121 arranged on one side (D1 direction side) of the driver unit 11, a second end face which is a wall portion 122 arranged on the other side (D2 direction side) of the driver unit 11, and a side face which is a wall portion 123 which surrounds the space between the first end face and the second end face and is centered on an axis line A1 passing through the first end face and the second end face (FIGS. 2B and 3B). In this embodiment, for the sake of simplicity of explanation, an example is shown in which the housing 12 has a substantially cylindrical shape with both end faces. For example, the distance between the wall portion 121 and the wall portion 122 is 10 mm, and the walls 121 and 122 are circles with a radius of 10 mm. However, these are merely examples and do not limit the present invention. For example, the housing 12 may have a substantially dome shape with walls at the ends, may have a hollow substantially cubic shape, or may have other three-dimensional shapes. In addition, there is no limitation on the material that constitutes the housing 12. The housing 12 may be made of a rigid body such as synthetic resin or metal, or may be made of an elastic body such as rubber.

[0012] <Sound holes 121a, 123a> The wall of the housing 12 is provided with a sound hole 121a (first sound hole) for guiding the acoustic signal AC1 (first acoustic signal) emitted from the driver unit 11 to the outside, and a sound hole 123a (second sound hole) for guiding 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 signals AC1 and AC2 can be respectively guided to the outside, the sound holes 121a and 123a do not have to be through holes.

[0013] The acoustic signal AC1 emitted from the sound hole 121a reaches the ear canal of the user and is heard by the user. On the other hand, an acoustic signal AC2, which is an inverse phase signal of the acoustic signal AC1 or an approximation signal of the inverse phase signal, is emitted from the sound hole 123a. A part of this acoustic signal AC2 cancels out a part (sound leakage component) of the acoustic signal AC1 emitted from the sound hole 121a. 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 position P2 (second position) based on position P1 (first position) is 11 Set the predetermined value η th 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 expressed as follows: 12 A predetermined value ω th Here, the position P1 (first point) is a predetermined point where the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) arrives. On the other hand, the position P2 (second point) is a predetermined point that is farther away from the acoustic signal output device 10 than the position P1 (first point). The predetermined value η th is the attenuation rate η of any or a specific acoustic signal (sound) due to air propagation at position P2 (second point) relative to position P1 (first point). 21 In addition, the predetermined value ω this the attenuation of any or specific acoustic signal (sound) due to air propagation at position P2 (second point) relative to position P1 (first point), η 22 That is, the acoustic signal output device 10 of the present embodiment has an attenuation rate η 11 is the decay rate η 21 A predetermined value η smaller than th It is designed to be equal to or less than the attenuation η 12 is the attenuation η 22 A predetermined value ω greater than th The acoustic signal AC1 is propagated through the air from position P1 to position P2, and is attenuated due to this air propagation and the acoustic signal AC2. 11 is the ratio (AMP2(AC1) / AMP1(AC1)) of the magnitude AMP2(AC1) of the acoustic signal AC1 at the position P2 attenuated due to air propagation and the acoustic signal AC2 to the magnitude AMP1(AC1) of the acoustic signal AC1 at the position P1. Also, the attenuation amount η 12 is the difference between the magnitude AMP1(AC1) and the magnitude AMP2(AC1) (|AMP1(AC1)-AMP2(AC1)|). On the other hand, when the acoustic signal AC2 is not assumed, an arbitrary or specific acoustic signal AC propagating through the air from the position P1 to the position P2 is ar is attenuated due to air propagation, not due to the acoustic signal AC2. 21 is the acoustic signal AC at position P1 ar The size of AMP1(AC ar ) attenuated due to air propagation (attenuated without being attributable to the acoustic signal AC2) at position P2 ar Size of AMP2 (AC ar ) ratio (AMP2(AC ar ) / AMP1(AC ar )) In addition, the attenuation η 22 is the magnitude AMP1(AC ar ) and size AMP2(AC ar ) and the difference (|AMP1(AC ar )-AMP2(AC ar)|). An example of the magnitude of the acoustic signal is the sound pressure of the acoustic signal or the energy of the acoustic signal. The "sound leakage component" means, for example, a component of the acoustic signal AC1 emitted from the sound hole 121a that is likely to reach an area other than that of 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, the "sound leakage component" means a component of the acoustic signal AC1 that propagates in a direction other than the D1 direction. 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 part of the direct wave of the acoustic signal AC1 emitted from the sound hole 121a (sound leakage component) is offset by interference with at least a part of the direct wave of the acoustic signal AC2 emitted from the sound hole 123a. However, this does not limit the present invention, and this offsetting can occur with other than direct waves. That is, the 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 offset by at least one of the direct wave and the reflected wave of the acoustic signal AC2 emitted from the sound hole 123a. This makes it possible to suppress sound leakage.

[0014] The arrangement of the sound holes 121a and 123a is illustrated. Sound hole 121a (first sound hole) of this embodiment is provided in region AR1 (first region) of wall 121 arranged on one side of driver unit 11 (the D1 direction side from which acoustic signal AC1 is emitted) (FIGS. 1, 2A, 2B, 3B). That is, sound hole 121a opens toward the D1 direction (first direction) along axis A1. Also, sound hole 123a (second sound hole) of this embodiment is provided in region AR3 of wall 123 that contacts region AR between region AR1 (first region) of wall 121 of housing 12 and region AR2 (second region) of wall 122 arranged on the D2 direction side of driver unit 11 (the other side from which acoustic signal AC2 is emitted). In other words, if the center of the housing 12 is taken as the reference point and the direction between the D1 direction (first direction) and the opposite direction to the D1 direction is taken as the D12 direction (second direction) (Figure 3B), the sound hole 121a (first sound hole) is provided on the D1 direction side (first direction side) of the housing 12, and the sound hole 123a (second sound hole) is provided on the D12 direction side (second direction side) of the housing 12. For example, when the housing 12 has a first end face which is a wall portion 121 arranged on one side (D1 direction side) of the driver unit 11, a second end face which is a wall portion 122 arranged on the other side (D2 direction side) of the driver unit 11, and a side face which is a wall portion 123 which surrounds the space between the first end face and the second end face and is centered on an axis A1 along the emission direction (D1 direction) of the acoustic signal AC1 passing through the first end face and the second end face (FIGS. 2B and 3B), the sound hole 121a (first sound hole) is provided on the first end face, and the sound hole 123a (second sound hole) is provided on the side face. In this embodiment, no sound hole is provided on the wall portion 122 side of the housing 12. 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 a level required to offset the sound leakage component of the acoustic signal AC1, and the excess is perceived as sound leakage.

[0015] As illustrated in FIG. 2A and other figures, the sound hole 121a of this embodiment is disposed on or near the axis A1 along the emission direction (D1 direction) of the acoustic signal AC1. The axis A1 of this embodiment passes through the center or near the center of the area AR1 (first area) of the wall 121 disposed on one side (D1 direction side) of the driver unit 11 of the housing 12. For example, the axis A1 is an axis extending in the D1 direction through the central area of ​​the housing 12. That is, the sound hole 121a of this embodiment is provided at the central position of the area AR1 of the wall 121 of the housing 12. In this embodiment, for the sake of simplicity of explanation, an example is shown in which the edge shape 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 edge shape of the open end of the sound hole 121a may be other shapes such as an ellipse, a rectangle, or a triangle. Also, the open end of the sound hole 121a may be in a mesh shape. In other words, the open end of the sound hole 121a may be composed of a plurality of holes. Also, in this embodiment, for the sake of simplicity of explanation, an example is shown in which one sound hole 121a is provided in the area AR1 (first area) of the wall 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 121 of the housing 12.

[0016] It is desirable that the sound hole 123a (second sound hole) in this embodiment be disposed in consideration of, for example, the following points. (1) From the viewpoint of position: the sound hole 123a is positioned so that the propagation path of the sound leakage component of the sound signal AC1 to be cancelled out overlaps with the propagation path of the sound signal AC2 emitted from the sound hole 123a. (2) From the viewpoint of area: The propagation area of ​​the acoustic signal AC2 emitted from sound hole 123a and the frequency characteristics of housing 12 vary depending on the opening area of ​​sound hole 123a. Furthermore, the frequency characteristics of housing 12 affect the frequency characteristics of acoustic signal AC2 emitted from sound hole 123a, i.e., the amplitude at each frequency. Taking into consideration the propagation area and frequency characteristics of acoustic signal AC2 emitted from sound hole 123a, the opening area of ​​sound hole 123a is determined so that the sound leakage component is cancelled out by acoustic signal AC2 emitted from sound hole 123a in the area where the sound leakage component is to be cancelled out. From the above viewpoint, for example, it is desirable that the sound hole 123a (second sound hole) be configured as follows. For example, as illustrated in FIG. 2B, FIG. 3A, and FIG. 3C, it is preferable that the sound holes 123a (second sound holes) of this embodiment are provided in a plurality along a circumference (circle) C1 centered on an 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 cancelled by the acoustic signal AC2. In this embodiment, for the sake of simplicity, an example in which the plurality of sound holes 123a are provided on the circumference C1 is shown. However, it is sufficient that the plurality of sound holes 123a are provided along the circumference C1, and it is not necessary that all of the sound holes 123a are positioned strictly on the circumference C1.

[0017] Also, preferably, when 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 a first arc region, which is any of the unit arc regions, is the same or approximately the same as the sum of the opening areas of the sound holes 123a (second sound holes) provided along a second arc region, which is any of the unit arc regions excluding the first arc region. For example, as illustrated in FIG. 4, when the circumference C1 is equally divided into four unit arc regions C1-1, ..., C1-4, the sum of the opening areas of the sound holes 123a (second sound holes) provided along a first arc region (for example, unit arc region C1-1) which is one of the unit arc regions 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) provided along a second arc region (for example, unit arc region C1-2) which is one of the unit arc regions other than the first arc region. Note that, for the sake of simplicity of explanation, an example in which the circumference C1 is equally divided into four unit arc regions C1-1, ..., C1-4 is shown here, but this does not limit the present invention. In addition, "α1 and α2 are approximately the same" means that the difference between α1 and α2 is β% or less of α1. Examples of β% are 3%, 5%, 10%, etc. As a result, the sound pressure distribution of the acoustic signal AC2 emitted from the sound hole 123a provided along the first arc region and the sound pressure distribution of the acoustic signal AC2 emitted from the sound hole 123a provided along the second arc region are point-symmetric or approximately point-symmetric with respect to the axis A1. Preferably, the sums of the opening areas of the sound holes 123a (second sound holes) provided along each unit arc region are all the same or approximately the same for each unit arc region. As a result, the sound pressure distribution of the acoustic signal AC2 emitted from the sound hole 123a is point-symmetric or approximately point-symmetric with respect to the axis A1. As a result, the sound leakage component of the acoustic signal AC1 can be more appropriately cancelled out by the acoustic signal AC2.

[0018] More preferably, the multiple sound holes 123a are desirably provided along the circumference C1 with the same shape, size, and intervals. For example, multiple sound holes 123a with a width of 4 mm and a height of 3.5 mm are provided along the circumference C1 with the same shape, size, and intervals. When multiple sound holes 123a are provided along the circumference C1 with the same shape, size, and intervals, the sound leakage component of the acoustic signal AC1 can be more appropriately cancelled by the acoustic signal AC2. However, this does not limit the present invention.

[0019] Also preferably, sound hole 123a (second sound hole) is provided in a wall portion adjacent to area AR located on the other side (D2 direction side) of driver unit 11 (FIG. 3B). This allows the direct wave of acoustic signal AC2 emitted from the other side of driver unit 11 to be efficiently guided to the outside from sound hole 123a. As a result, the sound leakage component of acoustic signal AC1 can be more appropriately cancelled out by acoustic signal AC2.

[0020] In this embodiment, for the sake of simplicity, the edge of the open end of the sound hole 123a is shaped like a rectangle (the open end is square), but this does not limit the present invention. For example, the edge of the open end of the sound hole 123a may be shaped like a circle, an ellipse, a triangle, or other shapes. The open end of the sound hole 123a may be in a mesh shape. In other words, the open end of the sound hole 123a may be composed of multiple holes. There is no limit to the number of sound holes 123a, and a single sound hole 123a may be provided in the area AR3 of the wall part 123 of the housing 12, or multiple sound holes 123a may be provided.

[0021] It is desirable that the ratio S2 / S1 of the sum S2 of the opening areas of the sound holes 123a (second sound holes) to the sum S1 of the opening areas of the sound holes 121a (first sound holes) satisfies 2 / 3≦S2 / S1≦4 (details will be described later). This allows the sound leakage component of the acoustic signal AC1 to be appropriately cancelled out by the acoustic signal AC2.

[0022] The sound leakage suppression performance may also depend on the ratio between the area of ​​wall 123 in which sound hole 123a is provided and the opening area of ​​sound hole 123a. For example, assume that housing 12 has a first end face which is wall 121 arranged on one side (D1 direction side) of driver unit 11, a second end face which is wall 122 arranged on the other side (D2 direction side) of driver unit 11, and a side face which is wall 123 surrounding a space sandwiched between the first end face and the second end face around axis A1 along the emission direction (D1 direction) of acoustic signal AC1 passing through the first end face and the second end face, and sound hole 121a (first sound hole) is provided on the first end face, and sound hole 123a (second sound hole) is provided on the side face (FIGS. 2B and 3B). In such a case, it is desirable that the ratio S2 / S3 of the sum S2 of the opening areas of the sound holes 123a to the total area S3 of the side surfaces is 1 / 20≦S2 / S3≦1 / 5 (details will be described later). This allows the sound leakage component of the acoustic signal AC1 to be appropriately cancelled by the acoustic signal AC2. However, this does not limit the present invention.

[0023] <Usage status> FIG. 5A illustrates an example of a usage state of the acoustic signal output device 10. In the example of FIG. 5A, one acoustic signal output device 10 is attached to each of the right ear 1010 and the left ear 1020 of the user 1000. An arbitrary attachment mechanism is used to attach the acoustic signal output device 10 to the ear. The D1 direction side of each acoustic signal output device 10 faces the user 1000. The output signal output from the playback device 100 is input to the driver unit 11 of each acoustic signal output device 10, and the driver unit 11 emits an acoustic signal AC1 to the D1 direction side and emits an acoustic signal AC2 to the other side. The acoustic signal AC1 is emitted from the sound hole 121a, and the emitted acoustic signal AC1 enters the right ear 1010 and the left ear 1020 and is heard by the user 1000. On the other hand, an acoustic signal AC2, which is an inverse phase signal of the acoustic signal AC1 or an approximation signal of the inverse phase signal, is emitted from the sound hole 123a. This part of the acoustic signal AC2 cancels out the part (sound leakage component) of the acoustic signal AC1 emitted from the sound hole 121a.

[0024] <Experimental Results> The following are experimental results showing the sound leakage suppression effect of the acoustic signal output device 10 of this embodiment. In this experiment, as shown in Fig. 5B, the acoustic signal output device 10 was attached to both ears of a dummy head 1100 simulating a human head, and acoustic signals were observed at positions P1 and P2. Position P1 in this example is a position near the left ear 1120 of the dummy head 1100 (near the acoustic signal output device 10), and position P2 is a position 15 cm away from position P1 in an outward direction.

[0025] FIG. 6 illustrates the frequency characteristics of an acoustic signal observed at position P1 in FIG. 5B, FIG. 7 illustrates the frequency characteristics of an acoustic signal observed at position P2 in FIG. 5B, and FIG. 8 illustrates the difference (difference in sound pressure level at each frequency) between the frequency characteristics of an acoustic signal observed at position P1 and the frequency characteristics of an acoustic signal observed at position P2. The horizontal axis indicates frequency (Frequency [Hz]), and the vertical axis indicates sound pressure level (SPL) [dB]. The solid line graph illustrates the frequency characteristics when the acoustic signal output device 10 of this embodiment is used, and the dashed line graph illustrates the frequency characteristics when a conventional acoustic signal output device (open-ear type earphones) is used. As illustrated in FIG. 8, when the acoustic signal output device 10 of this embodiment is used, the acoustic signal observed at position P1 is significantly higher than when the conventional acoustic signal output device is used. Sound pressure It can be seen that there is a large difference between the sound pressure of the acoustic signal observed at position P2 and the sound pressure of the acoustic signal observed at position P3. This shows that the acoustic signal output device 10 of this embodiment is able to suppress sound leakage at position P2 more effectively than the conventional acoustic signal output device.

[0026] FIG. 9A illustrates the relationship between the ratio S2 / S1 of the sum S2 of the opening areas of the sound holes 123a (second sound holes) to the sum S1 of the opening areas of the sound holes 121a (first sound holes) 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 indicates the ratio S2 / S1, and the vertical axis indicates the sound pressure level (SPL) [dB] that represents the difference. r12h6 illustrates the results when the number of sound holes 121a is six and the number of sound holes 123a is four, and r12h12 illustrates the results when the number of sound holes 121a is six and the number of sound holes 123a is four. Hole 19A, when the ratio S2 / S1 of the sum S2 of the opening areas of the sound holes 123a to the sum S1 of the opening areas of the sound holes 121a is in the range of 2 / 3≦S2 / S1≦4, the acoustic signal observed at position P1 in particular Sound pressure It can be seen that there is a large difference between the sound pressure of the acoustic signal observed at position P1 and position P2. This indicates that the sound leakage suppression effect is large in this range. FIG. 9B illustrates an example of the relationship between the ratio S2 / S3 of the sum S2 of the opening areas of the sound holes 123a (second sound holes) to the total area S3 of the side surfaces, and 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 horizontal axis indicates the ratio S2 / S3, and the vertical axis indicates the sound pressure level (SPL) [dB] that represents the difference. The meanings of r12h6, r12h12, and r45h35 are the same as in FIG. 9A. As illustrated in FIG. 9B, when the ratio S2 / S3 of the sum S2 of the opening areas of the sound holes 123a (second sound holes) to the total area S3 of the side surfaces is in the range of 1 / 20≦S2 / S3≦1 / 5, and in particular, the acoustic signal observed at position P1 Sound pressure It can be seen that there is a large difference between the sound pressure of the acoustic signal observed at position P1 and position P2. This indicates that the sound leakage suppression effect is large in this range.

[0027] [Modification 1 of the first embodiment] In the first embodiment, an example was shown in which a plurality of sound holes 123a (second sound holes) of the same shape, size, and interval are provided along the circumference C1. However, this does not limit the present invention. A plurality of sound holes 123a of different shapes and / or sizes and / or intervals may be provided along the circumference C1. For example, as illustrated in Figs. 10A, 10B, 11A, 11B, and 12A, a plurality of sound holes 123a of different shapes and intervals may be provided in the wall portion 123 along the circumference C1, as illustrated in Fig. 12B, a plurality of sound holes 123a of different intervals may be provided in the wall portion 123 along the circumference C1, or as illustrated in Fig. 12C, a plurality of sound holes 123a of different shapes and sizes may be provided in the wall portion 123 along the circumference C1.

[0028] Even in such a 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) provided along a first arc region, which is one of the unit arc regions, is the same or approximately the same as the sum of the opening areas of the sound holes 123a provided along a second arc region, which is one of the unit arc regions other than the first arc region. More preferably, it is desirable that the sums of the opening areas of the sound holes 123a provided along each unit arc region for each unit arc region are all the same or approximately the same. For example, as illustrated in Figures 10A, 10B, 11A, and 11B, the number and sizes of the sound holes 123a provided in each unit arc area C1-1, C1-2, C1-3, and C1-4 are different from one another, but it is desirable that the sum of the opening area of ​​the sound holes 123a provided in unit arc area C1-1, the sum of the opening area of ​​the sound holes 123a provided in unit arc area C1-2, the sum of the opening area of ​​the sound holes 123a provided in unit arc area C1-3, and the sum of the opening area of ​​the sound holes 123a provided in unit arc area C1-4 are all identical or approximately identical to one another.

[0029] As long as the plurality of sound holes 123a are arranged along the circumference C1, all the sound holes 123a do not necessarily have to be arranged strictly on the circumference C1. For example, as shown in Fig. 12A, Fig. 12B, and Fig. 12C, all the sound holes 123a do not necessarily have to be arranged on the circumference C1, but these plurality of sound holes 123a may be arranged along the circumference C1. The position of the circumference C1 is not limited to that exemplified in the first embodiment, and may be a circumference centered on the axis A1.

[0030] Furthermore, as long as a sufficient sound leakage suppression effect can be obtained, all sound holes 123a do not have to be arranged along the circumference C1. In other words, some sound holes 123a may be arranged at positions that are off the circumference C1. Also, as long as a sufficient sound leakage suppression effect can be obtained, there is no limit to the number of sound holes 123a, and one sound hole 123a may be provided.

[0031] [Modification 2 of the First Embodiment] In the first embodiment, a configuration in which one sound hole 121a is arranged at a central position (hereinafter simply referred to as "central position") of an area AR1 (area of ​​a wall arranged on one side of the driver unit) of a wall 121 of the housing 12 is illustrated. However, a plurality of sound holes 121a may be provided in the area AR1 of the wall 121 of the housing 12, or the sound hole 121a may be shifted to an eccentric position shifted from the center (central position) of the area AR1 of the wall 121 of the housing 12. For example, as illustrated in FIG. 13A, one sound hole 121a may be provided at an eccentric position on the area AR1 (a position on the axis A12 parallel to the axis A1 shifted from the axis A1) (hereinafter simply referred to as "eccentric position"). In other words, the position of one sound hole 121a provided in the area AR1 may be shifted to an eccentric position. Alternatively, as illustrated in FIG. 13B, a plurality of sound holes 121a may be provided in the region AR1, and the plurality of sound holes 121a may be biased to an eccentric position on the axis A12 parallel to the axis A1, which is offset from the axis A1. In other words, the positions of the plurality of sound holes 121a provided in the region AR1 may be biased to an eccentric position. That is, a single sound hole 121a may be provided, or a plurality of sound holes 121a may be provided, and the sound hole 121a may be biased to the center position of the region AR1 of the wall portion 121 of the housing 12, or may be biased to an eccentric position. 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.

[0032] The resonant frequency of the housing 12 can be controlled by the arrangement of the sound holes 121a provided in the area AR1 (for example, the number, size, interval, arrangement, etc. 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 arrangement of the sound holes 121a provided in the area AR1. For example, when the frequencies of the sound signals AC1 and AC2 become higher, their wavelengths become shorter, and it becomes difficult to align the phase so that the sound leakage 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 becomes to suppress the sound leakage of the sound signal AC1. Since the sound pressure levels of the sound signals AC1 and AC2 are high at the resonant frequency of the housing 12, if the resonant frequency of the housing 12 belongs to a high frequency band where it is difficult to suppress sound leakage, the sound leakage is perceived as being large. In order to solve this problem, the resonance frequency of the housing 12 may be controlled by setting the arrangement of the sound holes 121a as in the following Examples 2-1 and 2-2.

[0033] <Example 2-1> The arrangement of the sound holes 121a may be set so that the human hearing sensitivity to the resonant frequency of the housing 12 is low in a high frequency band where it is difficult to suppress sound leakage. For example, when the position of the sound hole 121a is shifted to a certain eccentric position, the predetermined frequency f th The human hearing sensitivity (ease of hearing) for acoustic signals with a resonant frequency above S d In addition, the predetermined frequency f of the housing 12 in which the sound hole 121a is provided at the center position is th The sensitivity of human hearing to acoustic signals with resonant frequencies above S c In this case, the hearing sensitivity S d is hearing sensitivity S c That is, the predetermined frequency f of the housing 12 in which the position of the sound hole 121a (first sound hole) is biased to a certain eccentric position (a position shifted from the center of the area of ​​the wall portion arranged on one side of the driver unit) is lower than th Human hearing sensitivity S to acoustic signals above the resonant frequency dis the predetermined frequency f of the housing 12 when it is assumed that the sound hole 121a is provided at the center position (the center of the area of ​​the wall portion arranged on one side of the driver unit). th Human hearing sensitivity S to acoustic signals above the resonant frequency c The position of the sound hole 121a may be shifted to such an eccentric position. The hearing sensitivity may be any index that indicates how easily a sound is heard. The higher the hearing sensitivity, the easier it is to hear. An example of hearing sensitivity is the reciprocal of the sound pressure level of a sound required for a human to perceive a sound of a standard loudness. For example, the hearing sensitivity is the reciprocal of the sound pressure level at each frequency on an equal loudness curve. At a given frequency f th The predetermined frequency f refers to the lower limit of a frequency band including a frequency at which it becomes difficult to cancel out the sound leakage component of the acoustic signal AC1 with the acoustic signal AC2. th Examples include 3000Hz, 4000Hz, 5000Hz, 6000Hz, etc.

[0034] <Example 2-2> Depending on the arrangement of the sound hole 121a, the resonance peak of the magnitude of the acoustic signal AC1 and / or the acoustic signal AC2 emitted from the housing 12 may be accentuated. For example, when the position of the sound hole 121a of the housing 12 is shifted to a certain eccentric position, the resonance peak of the magnitude of the acoustic signal AC1 emitted from the sound hole 121a and / or the acoustic signal AC2 emitted from the sound hole 123a may be accentuated at a certain frequency f th The sharpness of the peak above is Q d In addition, the magnitude of the acoustic signal AC1 emitted from the sound hole 121a of the housing 12 in which the sound hole 121a is provided at the center and / or the acoustic signal AC2 emitted from the sound hole 123a is set to a predetermined frequency f th The sharpness of the peak above is Q c In this case, the peak sharpness Q d is the sharpness of the peak Q c That is, the position of the sound hole 121a (first sound hole) of the housing 12 is shifted to a certain eccentric position, and ... signal AC1 (first sound signal) emitted from the sound hole 121a (first sound hole) and / or the sound signal AC2 (second sound signal) emitted from the sound hole 123a (second sound hole) of the housing 12 is shifted to a certain eccentric position, and the position of the sound signal AC1 (first sound signal) emitted from the sound hole 123a (second sound hole) of the housing 12 is shifted to a certain eccentric position.th Peak sharpness above Q d is a predetermined frequency f of 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) when it is assumed that the sound hole 121a is provided at the center position. th Peak sharpness above Q c In other words, the magnitude of the acoustic signal AC1 and / or the acoustic signal AC2 emitted from the housing 12 in which the position of the sound hole 121a is shifted to a certain eccentric position is smaller than that of the predetermined frequency f th The peaks in the above range correspond to the predetermined frequency f of the sound signal AC1 and / or the sound signal AC2 emitted from the housing 12 when it is assumed that the sound hole 121a is provided at the center position. th The peak is flatter than the above peak. The position of the sound hole 121a may be shifted to such an eccentric position.

[0035] When the position of one or more sound holes 121a is biased to an eccentric position, the distribution and opening area of ​​the sound holes 123a may be biased accordingly. For example, as shown in Fig. 13A or 13B, the position of one or more sound holes 121a provided in area AR1 is biased to an eccentric position on axis A12 displaced from axis A1, and as shown in Fig. 14A and 14B, the position of one or more sound holes 121a provided in area AR3 is biased to an eccentric position on axis A12 displaced from axis A1. 3 The opening area of ​​a may also be biased toward the eccentric position on the axis A12. In the example of Fig. 14A, the number of sound holes 123a provided along the unit arc region C1-3 far from the eccentric position on the axis A12 is less than the number of sound holes 123a provided along the unit arc region C1-1 closer to the eccentric position. In the example of Fig. 14B, ,shaftThe opening area of ​​each of the sound holes 123a provided along the unit arc region C1-3 far from the eccentric position on the line A12 is smaller than the opening area of ​​each of the sound holes 123a provided along the unit arc region C1-1 closer to the eccentric position. In other words, when 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 a first arc region (e.g., C1-3) which is one of the unit arc regions is smaller than the sum of the opening areas of the sound holes 123a provided along a second arc region (e.g., C1-1) which is one of the unit arc regions closer to the eccentric position than the first arc region. When the position of the sound hole 121a is biased toward the eccentric position, the distribution of the acoustic signal AC1 released to the outside from the sound hole 121a is also biased toward the eccentric position. Here, by biasing the distribution and opening area of ​​the sound holes 123a to the eccentric position, the distribution of the acoustic signal AC2 emitted to the outside from the sound holes 123a can also be biased to the eccentric position. This allows the emitted acoustic signal AC2 to sufficiently cancel out the sound leakage component of the acoustic signal AC1.

[0036] In order to control the resonance frequency of the housing 12 for other purposes, the sound hole 121a may be offset to an eccentric position that is offset from the center (central position) of the area AR1 of the wall portion 121 of the housing 12. a The size of the openings of the sound holes 121a, 123, the thickness of the walls of the housing 12, and the internal volume of the housing 12 affect the resonance frequency of the housing 12. Therefore, by controlling at least some of these, it is possible to increase or decrease the resonance frequency of the housing 12. a The larger the size of the opening of the sound holes 121a, 123, the thinner the wall of the sound hole 12, and the smaller the internal volume of the sound hole 12, the higher the resonant frequency of the sound hole 12. a The smaller the size of the opening, the thicker the wall of the housing 12, and the larger the internal volume of the housing 12, the lower the resonant frequency of the housing 12 can be.

[0037] [Third Modification of the First Embodiment] As described above, in the first embodiment and its modified examples 1 and 2, an acoustic signal AC2 that is an inverse phase signal or an approximation signal of an inverse phase signal of an acoustic signal AC1 is emitted from the sound hole 123a, and a part of the acoustic signal AC1 emitted from the sound hole 121a (sound leakage component) is cancelled by a part of the emitted acoustic signal AC2. For this purpose, when the direct wave of the acoustic signal AC1 is mainly emitted from the sound hole 121a, it is desirable that the direct wave of the acoustic signal AC2 is mainly emitted from the sound hole 123a. Since the reflected wave has a different propagation path from the direct wave, if the acoustic signal AC2 emitted from the sound hole 123a contains a reflected wave, the acoustic signal AC2 emitted from the sound hole 123a may show a different phase from the inverse phase signal or an approximation signal of the inverse phase signal of the acoustic signal AC1 emitted from the sound hole 121a, and the efficiency of canceling the sound leakage component may decrease. That is, it is desirable 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 that the direct wave of the acoustic signal AC2 is mainly emitted from the sound hole 123a (second sound hole). An example of such a configuration will be described below.

[0038] <Example 3-1> An echo suppressing material (e.g., sponge, paper, etc.) for suppressing echo may be provided in the internal region (e.g., regions AR2, AR3) of the wall of the housing 12. The wall of the housing 12 itself may be made of an echo suppressing material, or a sheet-like echo suppressing material may be fixed to the wall of the housing 12. Alternatively, the internal region of the wall of the housing 12 (e.g., regions AR2, AR3) may be made uneven to suppress echo. Alternatively, a sheet with an uneven surface shape that has an echo suppressing effect may be fixed to the internal region of the wall of the housing 12.

[0039] <Example 3-2> As illustrated in Figures 15A and 15B, the opening end of sound hole 123a (second sound hole) may be directed toward peripheral portion 112a on the other side 112 (D2 direction side) of driver unit 11, and sound hole 123a may be configured to mainly emit direct waves of acoustic signal AC2 (second acoustic signal) emitted from the other side 112 of driver unit 11.

[0040] <Example 3-3> As illustrated in FIG. 15B, wall portion 122 (area AR2) arranged on the other side of driver unit 11 is not in contact with driver unit 11 (not in contact when driver unit 11 is driven), and driver unit 11 and driver unit 1 1 The distance dis1 between the wall portion 122 arranged on the other side 112 of the driver unit 11 and the area AR2 may be 5 mm or less, and a direct wave of the acoustic signal AC2 (second acoustic signal) may be mainly emitted from the sound hole 123a (second sound hole). Note that the area AR2 being out of contact with the driver unit 11 while the driver unit 11 is driven means, for example, that the distance dis1 is greater than the amplitude of the other side 112 of the driver unit 11 being driven.

[0041] [Fourth Modification of the First Embodiment] As described above, the higher the frequency of the acoustic signals AC1 and AC2, the shorter their wavelengths become, and it becomes more difficult to cancel out the sound leakage component of the acoustic signal AC1 with the acoustic signal AC2. In some cases, it may be difficult to align the phases of the acoustic signals AC1 and AC2 at high frequencies, and conversely, it may be assumed that the sound leakage component of the acoustic signal AC1 is amplified by the acoustic signal AC2. Therefore, it may be better to suppress the emission of the high-frequency acoustic signal AC2 from the sound hole 123a. For this reason, a sound absorbing material that absorbs high-frequency acoustic signals may be provided in the housing 12. This sound absorbing material has a characteristic that the sound absorption coefficient for an acoustic signal of frequency f1 is greater than the sound absorption coefficient for an acoustic signal of frequency f2. However, frequency f1 is higher than frequency f2 (f1>f2). In other words, this 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 The frequency f2 is equal to or less than the predetermined frequency f2 th greater than the given frequency f2 th Examples of the frequency are 3000Hz, 4000Hz, 5000Hz, 6000Hz, etc. The sound absorption coefficient α of a sound absorbing material is the ratio of the energy of an acoustic signal input to the sound absorbing material to E in The energy of the acoustic signal reflected by the sound absorbing material or the energy of the acoustic signal passing through the sound absorbing material is E out In this case, α = (Ein -E out ) / E in Examples of such sound-absorbing materials include paper such as washi paper and calligraphy paper, nonwoven fabric, silk, and cotton.

[0042] <Example 4-1> At least one of the sound holes 123a (second sound holes) may be provided with sound absorbing material 13. For example, as illustrated in FIG. 16A, at least one of the sound holes 123a may be filled with sound absorbing material 13. At least one of the inside and outside of at least one of the sound holes 123a may be covered with sound absorbing material 13.

[0043] <Example 4-2> Sound absorbing material 13 may be provided in an area on the other side 112 (D2 direction side) of driver unit 11 inside housing 12. For example, as illustrated in FIG. 16B, sound absorbing material 13 may be fixed to area AR2 of wall portion 122 arranged on the other side 112 (D2 direction side) of driver unit 11. Sound absorbing material 13 may be fixed to the inside of wall portion 123.

[0044] <Example 4-3> Sound absorbing material 13 may be provided in at least any of sound holes 123a (second sound hole), and sound absorbing material 13 may be provided in an area on the other side 112 (D2 direction side) of driver unit 11 inside housing 12. For example, as illustrated in FIG. 16C, sound absorbing material 13 may be filled in at least any of sound holes 123a, and sound absorbing material 13 may be fixed to area AR2 of wall portion 122.

[0045] <Experimental Results> The results of an experiment 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 (without acoustic absorbent material) and the acoustic signal output device 10 in which the sound hole 123a is covered with acoustic absorbent material as exemplified in this modification was used (with acoustic absorbent material). Japanese paper was used as the acoustic absorbent material. In this experiment, as shown in FIG. 5B, the acoustic signal output device 10 was attached to both ears of a dummy head 1100 simulating a human head, and acoustic signals were observed at positions P1 and P2. Position P1 is a position near the left ear 1120 of the dummy head 1100 (near the acoustic signal output device 10), and position P2 is a position 15 cm away from position P1 toward the outside.

[0046] 17 illustrates the frequency characteristics of the acoustic signal observed at position P1 in FIG. 5B, FIG. 18 illustrates the frequency characteristics of the acoustic signal observed at position P2 in FIG. 5B, and FIG. 19 illustrates 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 horizontal axis indicates frequency (Hz), and the vertical axis indicates sound pressure level (SPL) (dB). The solid line graph illustrates the frequency characteristics when an acoustic signal output device 10 in which the sound hole 123a is covered with a sound absorbing material is used (with acoustic absorbent), and the dashed line graph illustrates the frequency characteristics when the acoustic signal output device 10 of the first embodiment is used (no acoustic absorbent). As illustrated in FIG. 19, in the frequency band of 2000 Hz or more, the acoustic signal observed at position P1 is generally lower when an acoustic signal output device 10 in which the sound hole 123a is covered with a sound absorbing material is used than when an acoustic signal output device 10 without a sound absorbing material is used. Sound pressure It can be seen that there is a large difference between the sound pressure of the acoustic signal observed at position P2 and the sound pressure of the acoustic signal observed at position P3. This indicates that in the frequency band of 2000 Hz or more, the sound leakage at position P2 is generally more effectively suppressed when using the acoustic signal output device 10 in which the sound hole 123a is covered with a sound absorbing material.

[0047] [Second embodiment] Next, a second embodiment of the present invention will be described. The second embodiment is a modified example of the first embodiment. In the following, differences from the matters described so far will be mainly described, and the same reference numbers will be used to simplify the description of matters already described.

[0048] In order to improve the sound quality of the acoustic signal output device 10 of the first embodiment or its modified example, the size of the driver unit 11 may need to be increased. However, in the first embodiment or its modified example, if the size of the driver unit 11 is increased, the size and weight of the acoustic signal output device 10 itself also increases. However, wearing the acoustic signal output device 10, which is large in size and weight, near the ear canal increases the burden on the ear and the foreign body sensation. For this reason, the housing with the sound hole and the driver unit 11 may be made separate, and these may be connected by a waveguide. This makes it possible to increase the size of the driver unit 11 without increasing the size and weight of the housing to be worn near the ear canal. This will be described in detail below.

[0049] The acoustic signal output device 20 of this embodiment is also a device for listening to sound that is worn without sealing the user's ear canal. As illustrated in Fig. 20, the acoustic signal output device 20 of this embodiment has a driver unit 11, a housing 22 having hollow portions AR21 and AR22 (first and second hollow portions), a housing 23 that houses the driver unit 11 inside, hollow waveguides 24 and 25 (first and second waveguides) that connect the housings 22 and 23, and hollow joint members 26 and 27 that connect the waveguides 24 and 25 to the housing 22.

[0050] <Driver unit 11> 20, the driver 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 inverse phase signal of the acoustic signal AC1 or an approximation signal of the inverse phase signal to the other side (D4 direction side). The configuration of the driver unit 11 is the same as that of the first embodiment, except that the D1 direction is replaced with the D3 direction, and the D2 direction is replaced with the D4 direction.

[0051] <Case 23> As illustrated in FIG. 20, the housing 23 is a hollow member having a wall on the outside, and houses the driver unit 11 inside. There is no limitation on the shape of the housing 23, but for example, it is desirable that the shape of the housing 23 is rotationally symmetric (line symmetric) or approximately rotationally symmetric about an axis A2 extending along the D3 direction. In this embodiment, for the sake of simplicity of explanation, an example is shown in which the housing 23 is approximately cylindrical with both end faces. However, this is only one example and does not limit the present invention. For example, the housing 23 may be approximately dome-shaped with walls at the ends, may be approximately hollow cubic, or may be another three-dimensional shape. One end 241 of the waveguide 24 is attached to the wall 231 of the housing 23 arranged on the surface 111 side on one side (D3 direction side) of the driver unit 11. Waveguide 24 (first waveguide) having one end 241 connected to one side (D3 direction side) of driver unit 11 in this manner guides acoustic signal AC1 emitted from face 111 of driver unit 11 to one side (D3 direction side) to the outside of housing 23. One end 251 of waveguide 25 is attached to wall 232 of housing 23 arranged on face 112 of the other side (D4 direction side) of driver unit 11. Waveguide 25 (second waveguide) having one end 251 connected to the other side (D4 direction side) of driver unit 11 in this manner guides acoustic signal AC2 emitted from face 112 of driver unit 11 to the other side (D4 direction side) to the outside of housing 23. There is no limitation on the material constituting housing 23. Housing 23 may be made of a rigid body such as synthetic resin or metal, or may be made of an elastic body such as rubber.

[0052] <Waveguide 24,25> As illustrated in Fig. 20, the waveguides 24 and 25 are hollow members formed in a tube shape, for example, and transmit the acoustic signals AC1 and AC2 inputted 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 tube-shaped, and may be any structure that guides the acoustic signal 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). There is no limitation on the length of the waveguides 24 and 25, but it is preferable that the length of the sound path of the waveguide 24 and the length of the sound path of the waveguide 25 are equal, or the difference between the length of the sound path of the waveguide 24 and the length of the sound path 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 path of the waveguide 24 (first waveguide) is L1, the length of the sound path of the waveguide 25 (second waveguide) is L2, n is an integer, and the acoustic signal AC1 (first acoustic signal) and the acoustic signal AC2 (second acoustic signal) include an acoustic signal with a wavelength λ, it is desirable to satisfy L1=L2+nλ. Note that the sound path is a path through which sound passes, and in the case of the waveguides 24 and 25 having the same inner diameter, a specific example of the length of the sound path of the waveguides 24 and 25 is the length of the waveguides 24 and 25. Note that there is no limitation on the material that constitutes the waveguides 24 and 25. The waveguides 24 and 25 may be made of a rigid body such as a synthetic resin or metal, or may be made of an elastic body such as rubber.

[0053] <Joint material 26> The joint member 26 is a hollow member having an open end 261 located on one side, a wall portion 262 which is a bottom surface located on the other side of the open end 261, and a wall portion 263 which is a side surface surrounding the space between the open end 261 and the wall portion 263, centered on the axis A1. lineA1 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. Also preferably, the joining member 26 is rotationally symmetrical with respect to the axis A1. In this embodiment, for the sake of simplicity, an example in which the wall portion 263 is cylindrical is shown, but the wall portion 263 may have other shapes, such as a prismatic shape. The other end 242 of the waveguide 24 is attached to the wall portion 263, and the acoustic signal AC1 emitted from the other end 242 of the waveguide 24 is introduced into the inside of the joining member 26 (the space between the open end 261 and the wall portion 263). The acoustic signal AC1 introduced into the inside of the joining member 26 is emitted from the open end 261. There is no limitation on the material constituting the joining member 26. The joining member 26 may be made of a rigid body such as a synthetic resin or metal, or may be made of an elastic body such as rubber.

[0054] <Joint material 27> Similarly, the joining member 27 is a hollow member having an open end 271 located on one side, a wall portion 272 which is a bottom surface located on the other side of the open end 271, and a wall portion 273 which is a side surface surrounding the space between the open end 271 and the wall portion 273 with the axis A1 as the center. The axis A1 in this embodiment passes through the open end 271 and the wall portion 273. Preferably, the axis A1 is perpendicular or approximately perpendicular to the wall portion 272. Also preferably, the joining member 27 is rotationally symmetrical with respect to the axis A1. In this embodiment, for the sake of simplicity of explanation, an example in which the wall portion 273 is cylindrical is shown, but the wall portion 273 may have other shapes such as a prism shape. The other end 252 of the waveguide 25 is attached to the wall portion 273, and the acoustic signal AC2 emitted from the other end 252 of the waveguide 25 is introduced into the inside of the joining member 27 (the space between the open end 271 and the wall portion 273). The acoustic signal AC2 introduced into the inside of the joining member 27 is emitted from the open end 271. There is no limitation on the material constituting the joining member 27. The joining member 27 may be made of a rigid body such as synthetic resin or metal, or may be made of an elastic body such as rubber.

[0055] <Case 22> 20, 21A-21C, 22A, and 22B, the housing 22 of this embodiment has a wall 221 located on one side (D1 direction side), a wall 222 located on the other side (D2 direction side), a wall 223 surrounding the space between the wall 221 and the wall 222, and a wall 224 dividing the space surrounded by the wall 221, the wall 222, and the wall 223 into a hollow portion AR21 (first hollow portion) and a hollow portion AR22 (second hollow portion). In this embodiment, the hollow portion AR21 and the hollow portion AR22 are disposed on the same axis A1 extending in the D1 direction, and for example, the central region of the hollow portion AR21 and the central region of the hollow portion AR22 are disposed on the same axis A1. The internal space of the hollow portion AR21 is preferably separated from the internal space of the hollow portion AR22 by a wall portion 224.

[0056] A joint member 26 to which the other end 242 of the waveguide 24 is attached is fixed or integrated with the inner wall of the hollow portion AR21, and an open end 261 side of the joint member 26 faces the wall portion 221 side. For example, the wall portion 262 side of the joint member 26 is fixed or integrated with 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 joint member 26 are arranged on the axis A1. As a result, the other end 242 of the waveguide 24 is connected to the hollow portion AR21 via the joint member 26, and the acoustic signal AC1 sent to the joint member 26 is emitted from the open end 261 toward the wall portion 221 side (D1 direction side). That is, for example, the joining member 26 is arranged on the axis A1, the open end 261 of the joining member 26 opens toward 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 emitted toward the direction D1 inside the hollow portion AR21.

[0057] A through hole 222a is provided in the wall 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 preferably arranged on the axis A1. The shape of the through hole 222a is not limited, but it is preferable that the opening of the through hole 222a is rotationally symmetrical with respect to the axis A1, and more preferably, the edge of the opening of the through hole 222a is circular. A joint member 27 to which the other end 252 of the waveguide 25 is attached is fixed or integrated with the outside of the wall 222 of the housing 22, and the open end 271 side of the joint member 27 is directed toward the through hole 222a. In this embodiment, the wall 272, the open end 271, and the center of the through hole 222a of the joint member 27 are arranged on the axis A1. As a result, the other end 252 of the waveguide 25 is connected to the hollow portion AR22 via the joining member 27, and the acoustic signal AC2 sent to the joining member 27 is emitted from the open end 271 toward the internal space of the hollow portion AR22. For example, the acoustic signal AC2 is emitted from the open end 271 toward the wall portion 224 side (D1 direction side). That is, for example, the joining member 27 is disposed on the axis A1, the open end 271 of the joining 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 emitted toward the direction D1 inside the hollow portion AR22.

[0058] There is no limitation on the shape of the housing 22, but for example, it is desirable that the shape of the housing 22 is rotationally symmetric or approximately rotationally symmetric about the axis A1. In this embodiment, for the sake of simplicity of explanation, an example is shown in which the external shape of the housing 22 is an approximately cylindrical shape having wall portions 221 and 222 which are both end faces and wall portion 223 which is a side face. In addition, in this embodiment, an example is shown in which the wall portions 221, 222, and 224 are perpendicular or approximately perpendicular to the axis A1, and the wall portion 223 is parallel or approximately parallel to the axis A1. However, these are only examples and do not limit the present invention. For example, the external shape of the housing 22 may be an approximately dome shape having walls at the ends, may be an approximately hollow cube shape, or may be another three-dimensional shape. In addition, there is no limitation on the material constituting the housing 22. The housing 22 may be made of a rigid body such as a synthetic resin or metal, or may be made of an elastic body such as rubber.

[0059] <Sound holes 221a, 223a> A wall 221 of the hollow portion AR21 (first hollow portion) is provided with a sound hole 221a (first sound hole) for guiding to the outside an acoustic signal AC1 (first acoustic signal) introduced into the inside of the hollow portion AR21 by a waveguide 24 (first waveguide). A wall 223 of the hollow portion AR22 (second hollow portion) is provided with a sound hole 221a (first sound hole) for guiding to the outside an acoustic signal AC2 (second acoustic signal) introduced into the inside of the hollow portion AR22 by a waveguide 25 (second waveguide). sound hole twenty two 3 a (second sound hole). As with the sound hole 121a and the sound hole 123a in the first embodiment, the sound hole 221a and the sound hole 223a are, for example, through holes penetrating 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 guided to the outside, the sound hole 221a and the sound hole 223a do not have to be through holes.

[0060] The acoustic signal AC1 emitted from the sound hole 221a reaches the ear canal of the user and is heard by the user. On the other hand, an acoustic signal AC2, which is an inverse phase signal of the acoustic signal AC1 or an approximation signal of the inverse phase signal, is emitted from the sound hole 223a. A part of this acoustic signal AC2 cancels out a part (sound leakage component) of the acoustic signal AC1 emitted from the sound hole 221a. This makes it possible to suppress sound leakage.

[0061] The arrangement of the sound holes 221a and 223a is illustrated. The sound hole 221a (first sound hole) of this embodiment is provided in a wall 221 of the hollow portion AR21 arranged on one side (the D1 direction side from which the acoustic signal AC1 is emitted) of the joining member 26 (FIGS. 20, 21A, 21B, and 22A). Also, the sound hole 223a (second sound hole) of this embodiment is provided in a wall 223 in contact with the hollow portion AR22. That is, assuming that the center of the hollow portion AR22 is used as a reference and that the direction between the D1 direction (first direction) and the opposite direction to the D1 direction is the D12 direction (second direction) (FIG. 22A), the sound hole 221a (first sound hole) is provided on the D1 direction side (first direction side) of the housing 22, and the sound hole 223a (second sound hole) is provided on the D12 direction side (second direction side) of the housing 22. That is, the sound hole 221a opens in the D1 direction (first direction) along the axis A1, and the sound hole 223a opens in the D12 direction (second direction). For example, when the outer shape of the housing 22 has a first end face which is a wall portion 221 arranged on one side (D1 direction side) of the joining member 26, a second end face which is a wall portion 222 arranged on the other side (D2 direction side) of the joining member 26, and a side face which is a wall portion 223 surrounding a space sandwiched between the first end face and the second end face around 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 (FIGS. 21B and 22A), the sound hole 221a (first sound hole) is provided on the first end face, and the sound hole 223a (second sound hole) is provided on the side face. In this embodiment, no sound hole is provided on the wall portion 222 side of the housing 22. 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 will exceed the level required to offset the sound leakage component of the acoustic signal AC1, and this excess will be perceived as sound leakage.

[0062] As illustrated in FIG. 21A and other figures, the sound hole 221a of this embodiment is disposed on or near the axis A1 along the emission direction (D1 direction) of the acoustic signal AC1. The axis A1 of this embodiment passes through the center or near the center of the region of the wall portion 221 disposed on one side (D1 direction side) of the joining member 26. For example, the axis A1 is an axis extending in the D1 direction through the central region of the housing 22. That is, the sound hole 221a of this embodiment is provided at the central position of the region of the wall portion 221 of the housing 22. In this embodiment, for the sake of simplicity of explanation, an example is shown in which the edge shape 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 edge shape of the open end of the sound hole 221a may be other shapes such as an ellipse, a rectangle, or a triangle. The open end of the sound hole 221a may be in a mesh shape. In other words, the open end of the sound hole 221a may be composed of a plurality of holes. In this embodiment, for the sake of simplicity, an example is shown in which one sound hole 221a is provided in the wall 221 of the housing 22. However, this does not limit the present invention. For example, two or more sound holes 221a may be provided in the wall 221 of the housing 22.

[0063] As in the first embodiment, as illustrated in Fig. 21B and Fig. 22B, a plurality of sound holes 223a (second sound holes) of this embodiment are provided along a circumference C1 centered on an axis A1 along the emission direction of an acoustic signal AC1 (first acoustic signal). For the sake of simplicity, this embodiment shows an example in which a plurality of sound holes 223a are provided on the circumference C1. However, it is sufficient that the plurality of sound holes 223a are provided along the circumference C1, and all of the sound holes 223a do not necessarily have to be positioned strictly on the circumference C1.

[0064] Also, as in the first embodiment, preferably, 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, which is any of the unit arc regions, is the same or approximately the same as the sum of the opening areas of the sound holes 223a (second sound holes) provided along a second arc region, which is any of the unit arc regions excluding the first arc region (FIG. 22B).

[0065] As in the first embodiment, it is more preferable that the sound holes 223a are provided along the circumference C1 with the same shape, size and intervals, although this is not intended to limit the present invention.

[0066] In this embodiment, for the sake of simplicity, the edge of the open end of the sound hole 223a is shaped like a rectangle, but this does not limit the present invention. For example, the edge of the open end of the sound hole 223a may be shaped like a circle, an ellipse, a triangle, or other shapes. The open end of the sound hole 223a may be in a mesh shape. In other words, the open end of the sound hole 223a may be composed of multiple holes. There is no limit to the number of sound holes 223a, and the wall 223 of the housing 22 may have a single sound hole 223a or multiple sound holes 223a.

[0067] As in the first embodiment, it is desirable that the ratio S2 / S1 of the sum S2 of the opening areas of the sound holes 223a (second sound holes) to the sum S1 of the opening areas of the sound holes 221a (first sound holes) satisfies 2 / 3≦S2 / S1≦4. In addition, when the outer shape of the housing 22 has a first end face which is a wall portion 221 arranged on one side (D1 direction side) of the joining member 26, a second end face which is a wall portion 222 arranged on the other side (D2 direction side) of the joining member 26, and a side face which is a wall portion 223 surrounding the space sandwiched between the first end face and the second end face around 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 (FIGS. 21B and 22A), the ratio S2 / S1 of the sum S2 of the opening areas of the sound holes 221a (first sound holes) to the total area S3 of the side faces satisfies 2 / 3≦S2 / S1≦4. 2 It is desirable that the ratio S2 / S3 of the total sum S2 of the opening areas of 23a is 1 / 20≦S2 / S3≦1 / 5.

[0068] <Usage status> 23A and 23B are used to illustrate the use state of the acoustic signal output device 20. In the example of FIG. 23A, one acoustic signal output device 20 is attached to each of the right ear 1010 and the left ear (not shown) of the user 1000. An arbitrary attachment mechanism is used to attach the acoustic signal output device 20 to the ear. The housing 22 of the acoustic signal output device 20 is disposed on the ear canal 1011 side of the right ear 1010 and the left ear, and the D1 direction side of each is directed toward the ear canal 1011 side of the user 1000. The playback device 210 including the housing 23 is disposed on the back side of the auricle of the right ear 1010 and the left ear, respectively, and the housing 23 and the housing 22 are connected by the waveguides 24 and 25 as described above. The acoustic signal AC1 introduced from the driver unit 11 in the housing 23 to the hollow portion AR21 of the housing 22 is emitted from the sound hole 221a, and the emitted acoustic signal AC1 is heard by the user 1000. On the other hand, the acoustic signal AC2 introduced from the driver unit 11 in the housing 23 to the hollow portion AR22 of the housing 22 is guided through a sound hole 2 A portion of this acoustic signal AC2 is an inverse phase signal of the acoustic signal AC1 or an approximation signal of the inverse phase signal, and cancels out a portion (sound leakage component) of the acoustic signal AC1 emitted from the sound hole 221a.

[0069] As in the example of Fig. 23B, playback device 210 including housing 23 may be placed on the head on the front side of the right ear 1010 and the left ear pinna, and housing 23 and housing 22 may be connected by waveguides 24 and 25 as described above. The rest is the same as the example of Fig. 23A.

[0070] [Modification 1 of the second embodiment] In the second embodiment, an example was shown in which a plurality of sound holes 223a (second sound holes) of the same shape, size, and intervals are provided along the circumference C1. However, this does not limit the present invention. For example, sound holes 223a having the same arrangement as the sound holes 123a in the first modification of the first embodiment may be provided in the housing 22 (FIGS. 10A to 12C).

[0071] [Modification 2 of the second embodiment] In the second embodiment, a configuration has been exemplified in which one sound hole 221a is arranged at the center position of the wall portion 221 of the housing 22. However, similar to the second modification of the first embodiment, a plurality of sound holes 221a may be provided in the area of ​​the wall portion 221 of the housing 22, or the sound hole 221a may be biased to an eccentric position shifted from the center of the area of ​​the wall portion 221 of the housing 22. For example, sound holes 221a having the same arrangement as the arrangement of the sound holes 121a in the second modification of the first embodiment may be provided in the housing 22 (FIGS. 13A and 13B).

[0072] Also, similar to the second modification of the first embodiment, when the position of the single or multiple sound holes 221a is biased toward an eccentric position, the distribution and opening area of ​​the sound holes 223a may be biased accordingly. In other words, when the circumference C1 is equally divided into multiple unit arc regions, the sum of the opening areas of the sound holes 223a (second sound holes) provided along a first arc region that is one of the unit arc regions is equal to or larger than the sum of the opening areas of the sound holes 223a (second sound holes) provided along a second arc region that is one of the unit arc regions closer to the eccentric position than the first arc region. 2 For example, sound holes 223a may be provided in the housing 22 in the same arrangement as the sound holes 123a in the second modification of the first embodiment (FIGS. 14A and 14B). a The resonant frequency of the housing 22 may be controlled by controlling at least a portion of the size of the opening, the thickness of the walls of the housing 22, and the internal volume of the housing 22.

[0073] [Modification 3 of the second embodiment] A sound absorbing material having a sound absorption coefficient for a sound signal of frequency f1 described in Modification 4 of the first embodiment that is greater than the sound absorption coefficient for a sound signal of frequency f2 (f1>f2) may be provided in acoustic signal output device 20. The sound absorbing material may be provided on the other side 112 (D4 direction side) of driver unit 11 inside housing 23, or may be provided inside waveguide 25 (second waveguide), or may be provided at an end (open end portion) of waveguide 25, or may be provided in at least any of sound holes 223a (second sound holes), or may be provided inside hollow portion AR22 (second hollow portion). For example, in examples 4-1 to 4-3 of variant example 4 of the first embodiment, the housing 12 may be replaced with a hollow portion AR22, the sound hole 123a may be replaced with a sound hole 223a, the region on the other side 112 of the driver unit 11 may be replaced with the internal region of the hollow portion AR22, and the region AR2 of the wall portion 122 may be replaced with the region of the wall portion 222.

[0074] [Variation 4 of the second embodiment] By providing the joining members 26 and 27 as in the second embodiment, the emission directions of the acoustic signals AC1 and AC2 in the hollow portions AR21 and AR22 can be controlled. For example, the acoustic signal AC1 introduced from the other end 242 of the waveguide 24 can be emitted in the direction D1 along the axis A1 inside the hollow portion AR21, and the acoustic signal AC2 introduced from the other end 252 of the waveguide 25 can be emitted in the same direction D1 inside the hollow portion AR22. In this case, the sound pressure distribution of the acoustic signal AC1 emitted from the sound hole 221a and the acoustic signal AC2 emitted from the sound hole 223a can be made rotationally symmetric or approximately rotationally symmetric with respect to the axis A1. This makes it possible to appropriately suppress sound leakage. However, this does not limit the present invention. 24, 25A, 25B, 25C, and 26, the acoustic signal output device 20 may not have a joining member 26, the other end 242 of the waveguide 24 may be directly connected to the wall 223 of the hollow part AR21, and the acoustic signal AC1 sent to the other end 242 of the waveguide 24 may be emitted toward the inside of the hollow part AR21. Similarly, the acoustic signal output device 20 may not have a joining member 27, the other end 252 of the waveguide 25 may be directly connected to the wall 223 of the hollow part AR22, and the acoustic signal AC2 sent to the other end 252 of the waveguide 25 may be emitted toward the inside of the hollow part AR22.

[0075] In the second embodiment, an example was 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. (FIGS. 20, 21B, and 22A). However, the internal space of the hollow portion AR21 of the housing 22 does not have to be separated from the internal space of the hollow portion AR22. In such a case, it is preferable 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 in this configuration, the acoustic signal AC1 is emitted from the sound hole 221a, and the acoustic signal AC2 is emitted from the sound hole 223a.

[0076] [Third embodiment] A plurality of the acoustic signal output devices 10 described in the first embodiment or its modified example may be provided and controlled independently. This allows the sound pressure level of the acoustic signal AC1 emitted from a certain acoustic signal output device 10 and the sound pressure level of the acoustic signal AC2 emitted from another acoustic signal output device 10 to be controlled independently. For example, a certain acoustic signal output device 10 and another acoustic signal output device 10 may be driven in opposite phases or substantially opposite phases to independently control the levels (power) at each frequency. This allows the sound leakage components of the acoustic signals AC1 of each acoustic signal output device 10 to be offset by a portion of the acoustic signal AC2, as exemplified in the first embodiment, and allows the portions of the acoustic signals AC1 and AC2 output from the different acoustic signal output devices 10 to be offset. As a result, it becomes possible to more appropriately offset the sound leakage components. In this embodiment, for the sake of simplicity, an example is shown in which two acoustic signal output devices 10 are provided for one ear and are controlled independently. However, this does not limit the present invention, and three or more audio signal output devices 10 may be provided for one ear and controlled independently. Note that the same reference numbers are used to omit the description of matters already explained, but sub-numbers are used to distinguish between multiple components having the same configuration. For example, two audio signal output devices 10 are represented as audio signal output device 10-1 and audio signal output device 10-2, but the configuration of audio signal output devices 10-1 and 10-2 is the same as that of audio signal output device 10.

[0077] The acoustic signal output device 30 of this embodiment is a device for listening to sound that is worn without sealing the ear canal of a user. As illustrated in Fig. 27 and Fig. 28, the acoustic signal output device 30 of this embodiment has acoustic signal output devices 10-1 and 10-2, a circuit section 31, and a connecting section 32.

[0078] <Audio signal output device 10-1> The configuration of the acoustic signal output device 10-1 is the same as that of the acoustic signal output device 10 exemplified in the first embodiment and its modified example. That is, the acoustic signal output device 10-1 has a driver unit 11-1 (first driver unit) and a housing 12-1 (first housing part) that houses the driver unit 11-1 inside. The driver unit 11-1 emits an acoustic signal AC1-1 (first acoustic signal) to the D1-1 direction side (one side) based on an input output signal I (electrical signal representing an acoustic signal), and emits an acoustic signal AC2-1 (second acoustic signal) that is an inverse phase signal of the acoustic signal AC1-1 (first acoustic signal) or an approximate signal of the inverse phase signal to the D2-1 direction side (the other side). The wall part 121-1 of the housing 12-1 is provided with one or more sound holes 121a-1 (first sound holes) that lead out the acoustic signal AC1-1 (first acoustic signal) emitted from the driver unit 11-1 to the outside. A single or multiple sound holes 123a-1 (second sound holes) are provided in a wall 123-1 of the housing 12-1 to guide an acoustic signal AC2-1 (second acoustic signal) emitted from the driver unit 11-1 to the outside. The details of the configuration of the acoustic signal output device 10-1 are the same as those of the acoustic signal output device 10 described in the first embodiment. For example, a plurality of sound holes 123a-1 (second sound holes) are provided along a circumference C1-1 (first circumference) centered on an axis A1-1 (first axis) that is parallel or approximately parallel to a straight line extending in a direction D1-1 (first direction) (FIG. 29). For example, 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) provided along a first arc region that is any of the first unit arc regions is the same or approximately the same as the sum of the opening areas of the sound holes 123a-1 (second sound holes) provided along a second arc region that is any of the first unit arc regions excluding the first arc region.

[0079] <Audio signal output device 10-2> The configuration of the acoustic signal output device 10-2 is also the same as that of the acoustic signal output device 10 exemplified in the first embodiment and its modified examples. That is, the acoustic signal output device 10-2 has a driver unit 11-2 (second driver unit) and a housing 12-2 (second housing part) that houses the driver unit 11-2 inside. The driver unit 11-2 emits an acoustic signal AC1-2 (fourth acoustic signal) to the D1-2 direction side (one side) based on the input output signal II (electrical signal representing an acoustic signal), and emits an acoustic signal AC2-2 (third acoustic signal) that is an inverse phase signal of the acoustic signal AC1-2 or an approximate signal of the inverse phase signal to the D2-2 direction side (the other side). The phase of the acoustic signal AC1-2 (fourth acoustic signal) is the same as or approximate to the phase of the acoustic signal AC2-1 (second acoustic signal). The phase of the acoustic signal AC2-2 (third acoustic signal) is the same as or close to the phase of the acoustic signal AC1-1 (first acoustic signal). The driver unit 11-2 may be of the same design as the driver unit 11-1, or may be of a different design from the driver unit 11-1. For example, the driver unit 11-2 may be smaller than the driver unit 11-1, or the performance of the driver unit 11-2 may be inferior to the driver unit 11-1. The wall 123-2 of the housing 12-2 is provided with one or more sound holes 123a-2 (third sound holes) for guiding the acoustic signal AC2-2 (third acoustic signal) emitted from the driver unit 11-2 to the outside. The wall 121-2 of the housing 12-2 is provided with one or more sound holes 121a-2 (fourth sound holes) for guiding the acoustic signal AC1-2 (fourth acoustic signal) emitted from the driver unit 11-2 to the outside. The detailed configuration of the acoustic signal output device 10-2 is the same as that of the acoustic signal output device 10 described in the first embodiment. For example, a plurality of sound holes 123a-2 (third sound holes) are provided along a circumference C1-2 (fourth circumference) centered on an axis A1-2 (fourth axis) that is parallel or approximately parallel to a straight line extending in a direction D1-2 (fourth direction) (FIG. 29).For example, when 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) provided along the third arc region, which is any of the fourth unit arc regions, is the same or approximately the same as the sum of the opening areas of the sound holes 123a-2 (third sound holes) provided along the fourth arc region, which is any of the fourth unit arc regions excluding the third arc region.

[0080] <Connection part 32> As illustrated in FIG. 27, FIG. 28, and FIG. 29, the connecting portion 32 fixes the housing 12-1 of the acoustic signal output device 10-1 and the housing 12-2 of the acoustic signal output device 10-2 to each other. In the example of FIG. 28, the outside of the wall portion 123-1 of the housing 12-1 of the acoustic signal output device 10-1 and the outside of the wall portion 123-2 of the housing 12-2 of the acoustic signal output device 10-2 are joined together. The sound hole 121a-1 (first sound hole) opens in a direction D1-1 (first direction) along the axis A1-1. The direction D1-1 is a direction along the axis A1-1. The sound hole 123a-1 (second sound hole) opens in a direction D12-1 (second direction) between the direction D1-1 (first direction) and the opposite direction to the direction D1-1 (first direction). The sound hole 121a-2 (fourth sound hole) opens toward a direction D1-2 (fourth direction) that is the same as or similar to the direction D1-1 (first direction). The direction D1-2 is along the axis A1-2. The sound hole 123a-2 (third sound hole) opens toward a direction D12-2 (third direction) between the direction D1-2 (fourth direction) and the opposite direction to the direction D1-2 (fourth direction). However, this arrangement is merely an example and does not limit the present invention.

[0081] As illustrated in Figures 27, 28, and 29, it is preferable that sound hole 121a-1 (first sound hole) and sound hole 121a-2 (fourth sound hole) are plane-symmetric or approximately plane-symmetric with respect to a reference plane P31 including a straight line parallel or approximately parallel to a straight line (axis A1-1) extending in direction D1-1 (first direction). Similarly, it is preferable that sound hole 123a-1 (second sound hole) and sound hole 123a-2 (third sound hole) are plane-symmetric or approximately plane-symmetric with respect to reference plane P31. More preferably, housing 12-1 (first housing part) and housing 12-2 (second housing part) are plane-symmetric or approximately plane-symmetric with respect to reference plane P31.

[0082] <Circuit part 31> Circuit unit 31 is a circuit that uses an input signal, which is an electrical signal representing an acoustic signal, as an input, and outputs output signal I, which is an electrical signal for driving driver unit 11-1, and output signal II, which is an electrical signal for driving driver unit 11-2. Output signal I and output signal II are electrical signals representing an acoustic signal, and output signal II is an inverse phase signal of output signal I or an approximation signal of said inverse phase signal. An example of the configuration of circuit unit 31 is shown below.

[0083] <Configuration example 1 of circuit section 31> The circuit section 31 illustrated in FIG. 30A has a phase inversion section 311 which is a phase inversion circuit. An input signal input to the circuit section 31 is output as is as an output signal I and supplied to the driver unit 11-1. Furthermore, the input signal input to the circuit section 31 is also input to the phase inversion section 311. The phase inversion section 311 outputs an inverse phase signal of the input signal or an approximation signal of the inverse phase signal as an output signal II. The output signal II is supplied to the driver unit 11-2.

[0084] <Configuration example 2 of circuit unit 31> The circuit section 31 illustrated in FIG. 30B has a level correction section 312, a phase control section 313, and a delay correction section 314. The input signal input to the circuit section 31 is input to the level correction section 312 and the delay correction section 314. The level correction section 312 adjusts the level of each frequency band of the input signal, and outputs the band level adjusted signal obtained thereby. That is, if the designs (diameter, structure, etc.) of the driver units 11-1 and 2 are different from each other, the frequency characteristics of the acoustic signals output from the driver units 11-1 and 2 are also different. The difference in the frequency characteristics of the acoustic signals output from the driver units 11-1 and 2 is related to the cancellation effect of sound leakage. For example, if the housings 12-1 and 12-2 are plane symmetrical with respect to the reference plane P31, it is desirable that the frequency characteristics of the acoustic signals output from the driver units 11-1 and 2 are the same in order to enhance the cancellation effect of sound leakage. Therefore, it is desirable to adjust the output signal so that the frequency characteristics of the acoustic signals output from the driver units 11-1 and 2 are the same. On the other hand, when the housings 12-1 and 12-2 are not plane-symmetrical with respect to the reference plane P31, it is desirable to adjust the balance of the frequency characteristics of the acoustic signals output from the driver units 11-1 and 11-2 in accordance with the asymmetry so that the cancellation effect of the sound leakage is increased. The level correction unit 312 achieves this by adjusting the level of each band of the input signal. The band level adjusted signal output from the level correction unit 312 is input to the phase control unit 313. The phase control unit 313 generates an inverse phase signal of the band level adjusted signal or an approximation signal of the inverse phase signal, and outputs this as the 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 can generate an inverse phase signal of the band level adjusted signal or an approximation signal of the inverse phase signal by taking into account the phase characteristics of the level correction unit 312. The output signal II is supplied to the driver unit 11-2. In addition, the delay correction unit 314 outputs the output signal I in which the delay amount of the input signal is adjusted. That is, when a delay occurs in the processing (filter processing) of the level correction unit 312 and the phase control unit 313, SlowDelay correction unit 314 adjusts the amount of delay. This adjusts the phase of the acoustic signal output from driver units 11-1 and 11-2, and improves the sound leakage suppression effect. Output signal I is supplied to driver unit 11-1. As described above, in configuration example 2 of circuit unit 31, output signal I and output signal II based on the input signal can be controlled independently.

[0085] <Configuration example 3 of circuit unit 31> As described above, the higher the frequency of the acoustic signals AC1 and AC2, the shorter their wavelengths become, making it difficult to cancel out the sound leakage component of the acoustic signal AC1 with the acoustic signal AC2. For example, this cancellation becomes difficult in a frequency range exceeding 6000 Hz. Therefore, in such a high frequency band, the acoustic signal AC2 for suppressing the sound leakage component may actually promote sound leakage. On the other hand, in earphones, the level of the low frequency range is weak, so the effect of sound leakage is also small. For example, the effect of sound leakage is small in a frequency range below 2000 Hz. Therefore, the importance of the acoustic signal AC2 for suppressing the sound leakage component in such a low frequency band is low. Furthermore, the human hearing sensitivity to acoustic signals with frequencies from 2000 Hz to 6000 Hz is relatively high. In other words, 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.

[0086] From the above viewpoints, when the user hears the acoustic signal AC1 emitted from the sound hole 121a-1 of the acoustic signal output device 10-1, the frequency band of the acoustic signal emitted from the acoustic signal output device 10-2 may be more restricted than the frequency band of the acoustic signal emitted from the acoustic signal output device 10-1. That is, the frequency bandwidth BW-2 of the acoustic signal AC2-2 and the acoustic signal AC1-2 (the third acoustic signal and the fourth acoustic signal) emitted from the driver unit 11-2 (the second driver unit) may be narrower than the frequency bandwidth BW-1 of the acoustic signals AC1-1 and AC2-1 (the first acoustic signal and the second acoustic signal) emitted from the driver unit 11-1 (the first driver unit).

[0087] Example 31-1: For example, the magnitude (level) of the high frequency side of the acoustic signals AC2-2 and AC1-2 may be suppressed more than the magnitude of the high frequency side of the acoustic signals AC1-1 and AC2-1. That is, the frequency f 31 The magnitude of the components above (first frequency) is equal to or greater than the frequency f of the acoustic signals AC1-1 and AC2-1 (first acoustic signal and second acoustic signal) emitted from the driver unit 11-1 (first driver unit). 31 For example, when the driver unit 11-2 is a frequency f 31 The acoustic signal AC2-2 and the acoustic signal AC1-2 in which the above frequency bands are suppressed may be output. 31 Examples include 3000Hz, 4000Hz, 5000Hz, and 6000Hz.

[0088] Example 31-2: For example, the magnitude of the low-frequency side of the acoustic signals AC2-2 and AC1-2 may be suppressed more than the magnitude of the low-frequency side of the acoustic signals AC1-1 and AC2-1. That is, the frequency f 32 The magnitude of the components below the frequency f (second frequency) of the acoustic signals AC1-1 and AC2-1 (first acoustic signal and second acoustic signal) emitted from the driver unit 11-1 (first driver unit) 32 For example, when the driver unit 11-2 is a frequency f 32 The acoustic signals AC2-2 and AC1-2 may be output with the following frequency bands suppressed: 32 Examples of this are 1000Hz, 2000Hz, and 3000Hz.

[0089] Example 31-3: For example, the magnitude of the high frequency side of the acoustic signals AC2-2 and AC1-2 may be suppressed more than the magnitude of the high frequency side of the acoustic signals AC2-1 and AC1-1, and the magnitude of the low frequency side of the acoustic signals AC2-2 and AC1-2 may be suppressed more than the magnitude of the low frequency side of the acoustic signals AC2-1 and AC1-1. 32 The following frequency bands and frequencies f 31 The above frequency bands are suppressed in the acoustic signal AC2-2 and the acoustic signal AC1-2 (for example, the frequency f 32 and frequency f 31 Alternatively, an acoustic signal AC2-2 and an acoustic signal AC1-2 each including only signals in a frequency band between the frequencies AC1-1 and AC2-2 may be output.

[0090] A third configuration example of the circuit section 31 that realizes these will be illustrated below. As illustrated in FIG. 30C, the circuit section 31 of this example has a level correction section 312, a phase control section 313, a delay correction section 314, and a bandpass filter section 315. An input signal input to the circuit section 31 is input to the bandpass filter section 315 and the delay correction section 314. The bandpass filter section 315 obtains and outputs a band-limited signal by limiting (narrowing) the band of the input signal. In the case of the above-mentioned example 31-1, the high-frequency side of the input signal (for example, frequency f 31 In the case of the above example 31-2, the low-frequency side of the input signal (for example, the frequency band f 32 In the case of the above example 31-3, the high-frequency side of the input signal (for example, the frequency band below the frequency f 31 above) and the lower frequency range (for example, frequency f 32 The signal with the suppressed frequency band below is output as a band-limited signal.

[0091] The band-limited signal is input to a level correction unit 312. The level correction unit 312 adjusts the level of each band of the band-limited signal, and outputs a band-level-adjusted signal obtained thereby. The band-level-adjusted signal output from the level correction unit 312 is input to a phase control unit 313. The phase control unit 313 generates an inverse phase signal of the band-level-adjusted signal or an approximation signal of the inverse phase signal, and outputs this as an output signal II. The output signal II is supplied to the driver unit 11-2. In addition, the delay correction unit 314 outputs an output signal I obtained by adjusting the delay amount of the input signal.

[0092] <Usage status> FIG. 31 illustrates an example of how the acoustic signal output device 30 is used. One acoustic signal output device 30 is worn on each of the right ear 1010 and left ear (not shown) of a user 1000 in FIG. 31. The D1 direction side of each acoustic signal output device 10-1 of the acoustic signal output device 30 faces the ear canal 1011 of the user 1000. Furthermore, the acoustic signal output device 10-2 is disposed at a position offset from the ear canal 1011. For example, when the acoustic signal output device 30 is worn on the ears, the sound hole 121a-1 (first sound hole) faces the ear canal 1011. 11 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 ear canal 10. 11The acoustic signal output device 30 is placed facing a direction other than the direction indicated by the arrows. Any attachment mechanism is used to attach the acoustic signal output device 30 to the ear. The acoustic signal AC1-1 (first acoustic signal) emitted from the sound hole 121a-1 (first sound hole) of the acoustic signal output device 10-1 is heard by the user 1000. Meanwhile, a part of the acoustic signal AC2-1 (second acoustic signal) emitted from the sound hole 123a-1 (second sound hole) cancels out a part of the acoustic signal AC1-1 (first acoustic signal) emitted from the sound hole 121a-1 (first sound hole). Also, a part of the acoustic signal AC2-2 (third acoustic signal) emitted from the sound hole 123a-2 (third sound hole) cancels out a part of the acoustic signal AC1-2 (fourth acoustic signal) emitted from the sound hole 121a-2 (fourth sound hole). Also, a part of the acoustic signal AC2-2 (third acoustic signal) emitted from the sound hole 123a-2 (third sound hole) cancels out a part of the acoustic signal AC2-1 (second acoustic signal) emitted from the sound hole 123a-1 (second sound hole). Also, a part of the acoustic signal AC1-2 (fourth acoustic signal) emitted from the sound hole 121a-2 (fourth sound hole) cancels out a 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, an acoustic signal AC1-1 (first acoustic signal) is emitted from the sound hole 121a-1 (first sound hole), an acoustic signal AC2-1 (second acoustic signal) is emitted from the sound hole 123a-1 (second sound hole), an acoustic signal AC2-2 (third acoustic signal) is emitted from the sound hole 123a-2 (third sound hole), and an acoustic signal AC1-2 (fourth acoustic signal) is emitted from the sound hole 121a-2 (fourth sound hole). In this case, the attenuation rate η of the acoustic signal AC1-1 (first acoustic signal) at position P2 (second point) based on position P1 (first point) is 11 is the attenuation rate of the acoustic signal due to air propagation at position P2 (second point) relative to position P1 (first point), η 21 A predetermined value η smaller than th In this case, the attenuation amount η of the acoustic signal AC1-1 (first acoustic signal) at the position P2 (second point) based on the position P1 (first point) is as follows: 12 is the attenuation of the acoustic signal due to air propagation at position P2 (second point) relative to position P1 (first point), η 22 A predetermined value ω greater than thThe above is the case. Note that position P1 (first point) in this embodiment is a predetermined point where the acoustic signal AC1-1 (first acoustic signal) emitted from the sound hole 121a-1 (first sound hole) arrives. On the other hand, position P2 (second point) in this embodiment is a predetermined point that is farther away from the acoustic signal output device 30 than position P1 (first point). As a result, sound leakage components from the acoustic signal output device 30 are cancelled out. Particularly in this embodiment, since the relative level of the driver unit 11-2 with respect to the driver unit 11-1 can be controlled, sound leakage can be further reduced compared to the case where one driver unit 11 is used as in the first embodiment.

[0093] Also, as explained in the configuration example 3 of the circuit unit 31, when the user listens to the acoustic signal AC1 emitted from the sound hole 121a-1 of the acoustic signal output device 10-1, a sufficient sound leakage suppression effect can be expected by limiting the frequency band of the acoustic signal emitted from the acoustic signal output device 10-2 to a frequency band of the acoustic signal emitted from the acoustic signal output device 10-1. For example, as in example 31-1, when the magnitude of the high-frequency side of the acoustic signals AC2-2 and AC1-2 (for example, the high-frequency side where it is difficult to suppress sound leakage by cancellation) is suppressed more than the magnitude of the high-frequency side of the acoustic signals AC2-1 and AC1-1, it is possible to suppress the sound leakage from being promoted in the high-frequency side. Also, for example, as in example 31-2, even if the magnitude of the low-frequency side of the acoustic signals AC2-2 and AC1-2 is suppressed more than the magnitude of the low-frequency side of the acoustic signals AC2-1 and AC1-1, the effect of sound leakage is small in applications where the level of low-frequency sound is weak, such as earphones. Furthermore, even if driver unit 11-2 is smaller in size or has lower performance than driver unit 11-1, a sufficient sound leakage suppression effect can be expected.

[0094] [Modification 1 of the third embodiment] The acoustic signal output devices 10-1 and 10-2 may be the acoustic signal output device 10 described in the modified example of the first embodiment. For example, as illustrated in Fig. 32A, the position of the sound hole 121a-1 (first sound hole) may be offset to a first eccentric position (a position on an axis A12-1 parallel to the axis A1-1 offset from the axis A1-1) offset from an axis A1-1 (first central axis) extending in a direction D1-1 (first direction) passing through a central region of the housing 12-1 (first housing part). 32B, 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) provided along a first arc region that is one of the first unit arc regions may be smaller than the sum of the opening areas of the sound holes 123a-1 (second sound holes) provided along a second arc region that is one of the first unit arc regions closer to the first eccentric position than the first arc region. 232B, when the circumference C1-2 (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 (fourth sound holes) provided along a third arc region that is one of the second unit arc regions may be smaller than the sum of the opening areas of the fourth sound holes provided along a fourth arc region that is one of the second unit arc regions closer to the fourth eccentric position than the third arc region. Even in such a case, it is preferable that the sound hole 121a-1 (first sound hole) and the sound hole 121a-2 (fourth sound hole) are plane-symmetric or approximately plane-symmetric with respect to a reference plane P31 including a straight line parallel or approximately parallel to a straight line (axis A1-1) extending in the direction D1-1 (first direction). Similarly, it is preferable that the sound hole 123a-1 (second sound hole) and the sound hole 123a-2 (third sound hole) are plane-symmetric or approximately plane-symmetric with respect to the reference plane P31. More preferably, it is preferable that the housing 12-1 (first housing part) and the housing 12-2 (second housing part) are plane-symmetric or approximately plane-symmetric 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, 2.

[0095] [Modification 2 of the third embodiment] In the third embodiment, the housing 12-1 (first housing section) of the acoustic signal output device 10-1 and the housing 12-2 (second housing section) of the acoustic signal output device 10-2 may be integrated. For example, as illustrated in FIG. 33A, the housing 12-1 of the acoustic signal output device 10-1 and the housing 12-2 of the acoustic signal output device 10-2 may be replaced with an integrated housing 12", and an area AR31 in which the driver unit 11-1 is housed and an area AR32 in which the driver unit 11-2 is housed may be separated by a wall section 351 provided inside the housing 12", separating the area AR31 from the area AR32. Note that if areas AR31 and AR32 are separated by wall 351, it is possible to prevent a portion of acoustic signal AC1-1 and a portion of acoustic signal AC1-2 from canceling out each other inside housing 12", and to prevent a portion of acoustic signal AC2-1 and a portion of acoustic signal AC2-2 from canceling out each other inside housing 12". For this reason, it is desirable that areas AR31 and AR32 are separated by wall 351. However, areas AR31 and AR32 do not have to be separated by wall 351. In other words, portions of acoustic signals AC1-1 and AC2-1 emitted from driver unit 11-1 may not be emitted from any of sound holes 121a-1, 123a-1, 121a-2, 123a-2, and may be canceled out inside housing 12". Even in this case, the components of the acoustic signals AC1-1, AC2-1, AC1-2, and AC2-2 that are not cancelled out inside the housing 12" are emitted to the outside from one of the sound holes 121a-1, 123a-1, 121a-2, and 123a-2. For example, the components of the acoustic signals AC1-1 and AC2-1 emitted from the driver unit 11-1 that are not cancelled out inside the housing 12" are sound holeThe sound signals are emitted from the driver units 11-1 and 11-2 to the outside through the sound holes 121a-1, 123a-1, 121a-2, and 123a-2. It goes without saying that these are offset by a part of the components of other acoustic signals emitted from any of the driver units 11-1 and 11-2 to the outside through any of the sound holes 121a-1, 123a-1, 121a-2, and 123a-2. Therefore, even in such a case, the sound leakage suppression effect can be obtained. Furthermore, even when housing 12-1 and housing 12-2 are integrated as housing 12", it is desirable that sound hole 121a-1 (first sound hole) and sound hole 121a-2 (fourth sound hole) are plane-symmetric or approximately plane-symmetric with respect to reference plane P31. Similarly, it is desirable that sound hole 123a-1 (second sound hole) and sound hole 123a-2 (third sound hole) are plane-symmetric or approximately plane-symmetric with respect to reference plane P31. It is more desirable that housing 12-1 (first housing part) and housing 12-2 (second housing part) are plane-symmetric or approximately plane-symmetric with respect to reference plane P31. Also, the sound-absorbing material described in the modification of the first embodiment may be provided inside housing 12" or in any of sound holes 121a-1, 121a-2, 123a-1, and 123a-2. The rest is the same as the third embodiment or its modification 1.

[0096] [Modification 3 of the third embodiment] Instead of the acoustic signal output devices 10-1 and 2 of the third embodiment, acoustic signal output devices 20-1 and 2 having the same configuration as the acoustic signal output device 20 of the second embodiment may be used. For example, as illustrated in Fig. 33B, the housings 22-1 and 22-2 of the acoustic signal output devices 20-1 and 2 may be joined by a connecting portion 32, and as described in the second embodiment, the housings 22-1 and 23-1 may be connected by waveguides 24-1 and 25-1, and the housings 22-2 and 23-2 may be connected by waveguides 24-2 and 25-2. The circuit section 31 supplies an output signal I to the driver unit 11-1 housed in the housing 23-1, and supplies an output signal II to the driver unit 11-2 housed in the housing 23-2. As explained in the second embodiment, acoustic signal AC1-1 sent from housing 23-1 to housing 22-1 via waveguides 24-1 and 25-1 is emitted from sound hole 221a-1, and acoustic signal AC2-1 is emitted from sound hole 223a-1. Similarly, acoustic signal AC1-2 sent from housing 23-2 to housing 22-2 via waveguides 24-2 and 25-2 is emitted from sound hole 221a-2, and acoustic signal AC2-2 is emitted from 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 and 123a-2, and the walls 121-1, 121-2, 122-1, 122-2, 123-1 and 123-2 are replaced with the housings 22-1 and 22-2, the sound holes 221a-1, 221a-2, 223a-1 and 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 by the waveguides 24-1 and 25-1, and may be connected to the housing 23-1 by the waveguides 24-2 and 25-2. In this case, circuit section 31 supplies output signal I to driver unit 11-1 housed in housing 23-1. Acoustic signal AC1-1 sent from housing 23-1 to housing 22-1 via waveguides 24-1 and 25-1 is emitted from sound hole 221a-1, and acoustic signal AC2-1 is emitted from sound hole 223a-1. Similarly, acoustic signal AC1-2 sent from housing 23-1 to housing 22-2 via waveguides 24-2 and 25-2 is emitted from sound hole 221a-2, and acoustic signal AC2-2 is emitted from sound hole 223a-2.Furthermore, the housing 23-1 may be connected to κ housings 22-κ via waveguides 24-κ and 25-κ, where κ=1,...,κ. max and κ max is an integer of 2 or more. In this case, circuit section 31 supplies output signal I to driver unit 11-1 housed in housing 23-1. Acoustic signal AC1-κ sent from housing 23-1 to housing 22-κ via waveguides 24-κ and 25-κ is emitted from sound hole 221a-κ, and acoustic signal AC2-κ is emitted from sound hole 223a-κ. In such a case, housing 23-2 and driver unit 11-2 may be omitted, and circuit section 31 may not output output signal II. Alternatively, housing 23-2 and driver unit 11-2 may not be omitted, and housing 23-2 may be further connected to another housing 22-γ via waveguides 24-γ and 25-γ. However, γ=κ max +1,…,γ max and γ max is κ maxis an integer greater than . In this case, the output signal II output from the circuit section 31 is further supplied to the driver unit 11-2 housed in the housing 22-2, and the acoustic signal AC1-γ sent from the housing 23-2 to the housing 22-γ through the waveguides 24-γ and 25-γ is emitted from the sound hole 221a-γ, and the acoustic signal AC2-γ is emitted from the sound hole 223a-γ. That is, it is sufficient that the acoustic signal AC1-1 (first acoustic signal) emitted from one of the single or multiple driver units is emitted to the outside from the sound hole 221a-1 (first sound hole). Also, it is sufficient that the acoustic signal AC2-1 (second acoustic signal) emitted from one of the single or multiple driver units is emitted to the outside from the sound hole 123a-1 (second sound hole). Also, the acoustic signal AC2-2 (third acoustic signal) emitted from any one of the single or multiple driver units may be emitted from the sound hole 123a-2 (third sound hole). Also, the acoustic signal AC1-2 (fourth acoustic signal) emitted from any one of the single or multiple driver units may be emitted to the outside from the sound hole 221a-2 (fourth sound hole). In other words, the acoustic signal AC1-1 (first acoustic signal) and the acoustic signal AC2-2 (third acoustic signal) may be the same signal emitted from the same driver unit, or they may be different signals emitted from different driver units. Similarly, the acoustic signal AC2-1 (second acoustic signal) and the acoustic signal AC1-2 (fourth acoustic signal) may be the same signal emitted from the same driver unit, or they may be different signals emitted from different driver units.

[0097] [Fourth embodiment] In the fourth embodiment, an example is shown in which an audio signal output device worn on both ears without sealing the ear canals of a user emits monaural audio signals with mutually inverted phases toward the left and right ears. From such an audio signal output device, not only toward the ear canal of the user, but also a part of the monaural audio signal is emitted toward the outside of the user. However, since the monaural audio signals emitted are mutually inverted in phase, the monaural audio signals propagating toward the outside of the user cancel each other out, reducing sound leakage.

[0098] As illustrated in FIG. 34A, the acoustic signal output device 4 of this embodiment has an acoustic signal output unit 40-1 (first acoustic signal output unit) worn on the right ear (one ear) 1010 of a user 1000, an acoustic signal output unit 40-2 (second acoustic signal output unit) worn on the left ear (the other ear) 1020, and a circuit unit 41.

[0099] <Circuit section 41> The circuit section 41 is a circuit that uses an input signal, which is an electric signal representing a monaural audio signal, as an input, and generates and outputs an output signal I to be supplied to the audio signal output section 40-1 and an output signal II to be supplied to the audio signal output section 40-2. The circuit section 41 of this embodiment has signal output sections 411 and 412 and a phase inversion section 413. An input signal is input to the phase inversion section 413 and the signal output section 412. The phase inversion section 413 outputs an output signal I (first output signal) that is an inverse phase signal of the input signal or an approximation signal of the inverse phase signal. The signal output section 411 (first signal output section) outputs the output signal I (first output signal) to the audio signal output section 40-1 (first audio signal output section). That is, the signal output unit 411 (first signal output unit) outputs an output signal I (first output signal) for outputting a monaural acoustic signal MAC1 (first monaural acoustic signal) from the acoustic signal output unit 40-1 (first acoustic signal output unit) attached to the right ear (one ear) 1010. Also, the signal output unit 412 outputs the input signal as it is to the acoustic signal output unit 40-2 (second acoustic signal output unit) as an output signal II (second output signal). That is, the signal output unit 412 outputs an output signal II (second output signal) for outputting a monaural acoustic signal MAC2 (second monaural acoustic signal) from the acoustic signal output unit 40-2 (second acoustic signal output unit) attached to the left ear (the other ear) 1020.

[0100] <Audio signal output units 40-1, 40-2> The acoustic signal output units 40-1 and 40-2 are devices for listening to sound that are worn on both ears of a user without sealing the ear canal. An output signal I is input to the acoustic signal output unit 40-1, which converts the output signal I into a monaural acoustic signal MAC1 (a phase that is the same or approximately the same as the phase of the monaural acoustic signal MAC1 is expressed as "+") and emits it toward the ear canal of the right ear 1010. An output signal II is input to the acoustic signal output unit 40-2, which converts the output signal II into a monaural acoustic signal MAC2 (a phase that is the same or approximately the same as the phase of the monaural acoustic signal MAC2 is expressed as "-") and emits it toward the ear canal of the left ear 1020. Here, the monaural acoustic signal MAC2 is an inverse phase signal of the monaural acoustic signal MAC1 or an approximation of the inverse phase signal of the monaural acoustic signal MAC1. However, even if the phases of the acoustic signals viewed by the left and right ears are inverted from each other, there is almost no problem in viewing. Although a portion of the emitted monaural acoustic signal MAC1 and the monaural acoustic signal MAC2 are also emitted to the outside of both ears, they cancel each other out because the monaural acoustic signal MAC1 and the monaural acoustic signal MAC2 are in opposite or nearly opposite phase to each other. That is, a portion of the emitted monaural acoustic signal MAC1 (first monaural acoustic signal) and a portion of the emitted monaural acoustic signal MAC2 (second monaural acoustic signal) interfere with each other and cancel each other out on the outer side (outer side of the user 1000, i.e., the opposite side to the right ear 1010) of the acoustic signal output unit 40-1 (first acoustic signal output unit) attached to the right ear 1010 (one ear) and / or on the outer side (outer side of the user 1000, i.e., the opposite side to the left ear 1020) of the acoustic signal output unit 40-2 (second acoustic signal output unit) attached to the left ear 1020 (the other ear). That is, as described above, the monaural audio signal MAC1 (first monaural audio signal) is output from the audio signal output unit 40-1 (first audio signal output unit), and the monaural audio signal MAC2 (second monaural audio signal) is output from the audio signal output unit 40-2 (second audio signal output unit). In this case, the attenuation rate η of the monaural audio signal MAC1 (first monaural audio signal) at the position P2 (second point) based on the position P1 (first point) is 11 is the attenuation rate of the acoustic signal due to air propagation at position P2 (second point) relative to position P1 (first point), η21 A predetermined value η smaller than th In this case, the attenuation amount η of the first monaural sound signal at the position P2 (second point) based on the position P1 (first point) is as follows: 12 is the attenuation of the acoustic signal due to air propagation at position P2 (second point) relative to position P1 (first point), η 22 A predetermined value ω greater than th The above is the case. However, position P1 (first point) in this embodiment is a predetermined position where monaural audio signal MAC1 (first monaural audio signal) arrives. Position P2 (second point) in this embodiment is a position farther from audio signal output unit 40-1 (first audio signal output unit) than position P1 (first point). As a result, sound leakage is suppressed.

[0101] [Modification 1 of the fourth embodiment] The acoustic signal output devices 10 according to the first embodiment or its modified examples may be used in place of the acoustic signal output units 40-1 and 40-2, or the acoustic signal output device 20 according to the second embodiment or its modified examples may be used.

[0102] As illustrated in FIG. 34B, the acoustic signal output device 4' of this modified example has an acoustic signal output device 10-1 (first acoustic signal output section) worn on the right ear (one ear) 1010 of the user 1000, an acoustic signal output device 10-2 (second acoustic signal output section) worn on the left ear (the other ear) 1020, and a circuit section 41; or has an acoustic signal output device 20-1 (first acoustic signal output section) worn on the right ear (one ear) 1010 of the user 1000, an acoustic signal output device 20-2 (second acoustic signal output section) worn on the left ear (the other ear) 1020, and a circuit section 41.

[0103] The acoustic signal output device 10-1 or 20-1 (first acoustic signal output unit) includes a driver unit 11-1 (first driver unit) that emits a monaural acoustic signal MAC1-1 (first acoustic signal, first monaural acoustic signal) in a D1-1 direction (one side) and emits a monaural acoustic signal MAC2-1 (second acoustic signal) that is an inverse phase signal of the monaural acoustic signal MAC1-1 or an approximation signal of the inverse phase signal of the monaural acoustic signal MAC1-1 to the other side of the D1-1 direction; The device includes a housing 12-1 or 22-1 (first housing) having a single or multiple sound holes 121a-1 or 221a-1 (first sound hole) provided in a wall portion thereof for guiding a monaural acoustic signal MAC1-1 (first acoustic signal) emitted from driver unit 11-1 to the outside, and a single or multiple sound holes 123a-1 or 223a-1 (second sound hole) for guiding a monaural acoustic signal MAC2-1 (second acoustic signal) emitted from driver unit 11-1 to the outside.

[0104] The acoustic signal output device 10-2 or 20-2 (second acoustic signal output unit) emits a monaural acoustic signal MAC1-2 (fourth acoustic signal, second monaural acoustic signal) that is the same as or similar to the monaural acoustic signal MAC2-1 (second acoustic signal) in the D1-2 direction (one side), and emits a monaural acoustic signal MAC2-2 (third acoustic signal) that is the same as or similar to the monaural acoustic signal MAC1-1 (first acoustic signal) in the other side of the D1-2 direction. and a housing 12-2, 22-2 (second housing) having, in a wall portion thereof, one or more sound holes 123a-2 or 223a-2 (third sound hole) for guiding to the outside a monaural acoustic signal MAC2-2 (third acoustic signal) emitted from driver unit 11-2, and one or more sound holes 121a-2 or 221a-2 (fourth sound hole) for guiding to the outside a monaural acoustic signal MAC1-2 (fourth acoustic signal) emitted from driver unit 11-2.

[0105] 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 rest of the detailed configuration of the acoustic signal output devices 10-1 and 10-2 is the same as that of the acoustic signal output device 10 of the first embodiment or its modification. Also, the detailed configuration of the acoustic signal output devices 20-1 and 20-2 is the same as that of the acoustic signal output device 20 of the second embodiment or its modification.

[0106] When the acoustic signal output device 4' is worn on both ears, the sound hole 121a-1 or 221a-1 of the acoustic signal output device 10-1 or 20-1 is directed toward the right ear 1010 (i.e., the D1-1 direction is directed toward the right ear 1010), and the sound hole 121a-2 or 2 21a-2 is directed toward the left ear 1020 (i.e., the D1-2 direction is directed toward the left ear 1020).

[0107] A monaural acoustic signal MAC1-1 (first monaural acoustic signal) is emitted from a sound hole 121a-1 or 221a-1 of the acoustic signal output device 10-1 or 20-1 (first acoustic signal output section) toward the ear canal of the right ear 1010. A monaural acoustic signal MAC1-2 (second monaural acoustic signal) is emitted from a sound hole 121a-2 or 221a-2 of the acoustic signal output device 10-2 or 20-2 (second acoustic signal output section) toward the ear canal of the left ear 1020. Here, the monaural acoustic signal MAC1-2 is an inverse phase signal of the monaural acoustic signal MAC1-1 or an approximation signal of the inverse phase signal of the monaural acoustic signal MAC1-1. However, even if the phases of the acoustic signals perceived by the left and right ears are inverted from each other, almost no problems occur in terms of viewing. Although a portion of the emitted monaural acoustic signal MAC1-1 and the monaural acoustic signal MAC1-2 are also emitted to the outside of both ears, they cancel each other out because the monaural acoustic signal MAC1-1 and the monaural acoustic signal MAC1-2 are in opposite or nearly opposite phase to each other. That is, a portion of the emitted monaural acoustic signal MAC1-1 (first monaural acoustic signal) and a portion of the emitted monaural acoustic signal MAC1-2 (second monaural acoustic signal) interfere with each other and cancel each other out on the outer side (outer side of the user 1000, i.e., the opposite side to the right ear 1010) of the acoustic signal output device 10-1 or 20-1 (first acoustic 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 to the left ear 1020) of the acoustic signal output device 10-2 or 20-2 (second acoustic signal output unit) worn on the left ear 1020 (the other ear). Furthermore, a monaural acoustic signal MAC2-1 is emitted from the sound hole 123a-1 or 223a-1 of the acoustic signal output device 10-1 or 20-1 (first acoustic signal output unit). A portion of the emitted monaural acoustic signal MAC2-1 cancels out a portion of the monaural acoustic signal MAC1-1 emitted from the sound hole 121a-1 or 221a-1. Furthermore, a monaural acoustic signal MAC2-2 is emitted from the sound hole 123a-2 or 223a-2 of the acoustic signal output device 10-2 or 20-2 (second acoustic signal output unit). A portion of the emitted monaural acoustic signal MAC2-2 cancels out a portion of the monaural acoustic signal MAC1-2 emitted from the sound hole 121a-2 or 221a-2.As a result, sound leakage is suppressed.

[0108] [Modification 2 of the fourth embodiment] The output signal I and the output signal II in the fourth embodiment or the first modified example of the fourth embodiment may be reversed. That is, the input signal input to the circuit unit 41 is input to the phase inversion unit 413 and the signal output unit 412, and the phase inversion unit 413 outputs the output signal II (second output signal) which is an inverse phase signal of the input signal or an approximation signal of the inverse phase signal. sound Alternatively, the signal output section 412 may output the input signal directly to the acoustic signal output section 40-1 (first acoustic signal output section) as the output signal I (first output signal).

[0109] [Fifth embodiment] In the fifth embodiment, a wearing method of an ear-mounted audio signal output device is illustrated. As described above, the conventional wearing method may cause problems such as a large burden on the ear and difficulty in stable wearing. In this embodiment, a new wearing method of the audio signal output device for solving such problems is illustrated.

[0110] <Wearing method 1> 35A to 36D are used to illustrate the wearing method 1. As illustrated in Fig. 35A to 35C, the acoustic signal output device 2100 of the wearing method 1 has a housing 2112 that emits an acoustic signal, a wearing unit 2121 (first wearing unit) that holds the housing 2112 and is configured to be worn on an upper part 1022 (first auricle part) of the auricle 1020, which is a part of the auricle 1020, and a wearing unit 2122 (second wearing unit) that holds the housing 2112 and is configured to be worn on a middle part 1023 (second auricle part) that is a part of the auricle 1020 different from the upper part 1022 (first auricle part) of the auricle 1020. The middle part 1023 is an intermediate part between the upper part 1022 (helix side) and the lower part 1024 (earlobe side) of the auricle 1020. Furthermore, in this embodiment, an example is shown in which the auricle 1020 is a human auricle, but the auricle 1020 may be an auricle of an animal other than a human (such as a chimpanzee).

[0111] The housing 2112 in this example may be any of the housings 12, 12", 22 exemplified in the first to fourth embodiments and their modified examples, or may be a housing of a conventional acoustic signal output device that emits an acoustic signal, such as an earphone. When the acoustic signal output device 2100 is worn, the housing 2112 is positioned so that the sound hole 2112a faces the ear canal 1021 and so that the ear canal 1021 is not blocked.

[0112] The mounting part 2121 (first mounting part) in this example has a fixing part 2121a (first fixing part) that grips the helix 1022a (end part) of the upper part 1022 (first auricle part) of the auricle 1020, and a support part 2121b that fixes the fixing part 2121a (first fixing part) to the housing 2112. One end of the support part 2121b holds a specific area of ​​the outer wall part of the fixing part 2121a, and the other end of the support part 2121b holds a specific area H1 (first holding area) of the outer wall part of the housing 2112. One end of the support part 2121b may be fixed to a specific area of ​​the wall part of the fixing part 2121a, or may be integrated with the wall part of the fixing part 2121a at the specific area. Similarly, the other end of the support part 2121b may be fixed to a specific region H1 of the outer wall of the housing 2112, or may be integrated with the outer wall of the housing 2112 at the specific region H1. In this manner, the support part 2121b holds the housing 2112 from the outer side (first outer side) of the specific region H1 of the wall of the housing 2112. In this example, when the fixing part 2121a is attached to 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 part 2121a (first fixing part) 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. The housing 2112 is configured to be suspended by the mounting part 2121 (first mounting part) including the fixing part 2121a (first fixing part) that grips the helix 1022a. That is, the fixing part 2121a grips the helix 1022a from above the auricle 1020, and the housing 2112 is suspended by one end of the support part 2121b that holds the fixing part 2121a at the other end. A reaction force against the weight of the housing 2112 suspended in this manner is supported by the inner wall surface of the fixing part 2121a. For example, this reaction force is supported by the inner wall surface of the fixing part 2121a that is disposed perpendicular or approximately perpendicular to the direction of the reaction force. In this configuration, the weight of the housing 2112 can be supported even if the gripping force of the fixing part 2121a is small. The smaller the gripping force of the fixing part 2121a, the smaller the burden on the auricle 1020, and therefore the burden on the ear can be reduced. The fixed portion 2121a may have any specific shape.An example of the fixing part 2121a is a member having a hollow shape with a C-shape or U-shape in cross section, and configured to hold the earlobe 1022a in a state where the earlobe 1022a is in contact with the inner wall surface 2121aa (for example, FIG. 36A to FIG. 36D). For example, the fixing part 2121a having an ear cuff shape can be exemplified.

[0113] The mounting part 2122 (second mounting part) in this example has a fixing part 2122a (second fixing part) that grips an end of the middle part 1023 (second auricle part) of the auricle 1020, and a support part 2122b that fixes the fixing part 2122a (second fixing part) to the housing 2112. One end of the support part 2122b holds a specific area of ​​the outer wall part of the fixing part 2122a, and the other end of the support part 2122b holds a specific area H2 (second holding area) of the outer wall part of the housing 2112. The area H2 is different from the above-mentioned area H1. One end of the support part 2122b may be fixed to a specific area of ​​the wall part of the fixing part 2122a, or may be integrated with the wall part of the fixing part 2122a at the specific area. Similarly, the other end of the support part 2122b may be fixed to a specific region H2 of the outer wall of the housing 2112, or may be integrated with the outer wall of the housing 2112 at the specific region H2. In this manner, the support part 2122b holds the housing 2112 from the outer side (a second outer side different from the first outer side) of the specific region H2 of the wall of the housing 2112. In this example, when the fixing part 2122a is attached to the end of the middle part 1023 of the auricle 1020, the outer side (second outer side) of the region H2 becomes the middle part 1023 side of the auricle 1020. In this manner, the housing 2112 is held by the mounting part 2121 (first mounting part) at the upper part 1022 of the auricle 1020 from the outer side (first outer side) of the region H1 as described above, and is further held by the mounting part 2122 (second mounting part) at the middle part 1023 of the auricle 1020 from the outer side (second outer side different from the first outer side) of the region H2. This stabilizes the position of the housing 2112 mounted on the auricle 1020. In addition, since the housing 2112 is held by the mounting part 2121 (first mounting part) and the mounting part 2122 (second mounting part) at different parts (upper part 1022 and middle part 1023) of the auricle 1020, the burden on the auricle 1020 caused by mounting can be distributed. Furthermore, the housing 2112 is attached to the auricle 1020 by attachment parts 2121, 2122 that grip the ends of the auricle 1020. Such attachment parts 2121, 2122 do not interfere with the temples of glasses or the strings of a mask that are hooked onto the back side of the auricle 1020. The fixing part 2122a may have any specific shape.An example of the fixing part 2122a is a member having a hollow shape with a C-shape or U-shape in cross section, and configured to grip the middle part 1023 of the auricle 1020 with the inner wall surface 2122aa in contact with the helix 1022a. For example, the fixing part 2122a having an ear cuff shape can be exemplified.

[0114] There is no limitation on the material constituting the mounting portion 2121 and the mounting portion 2122. The mounting portion 2121 and the mounting portion 2122 may be made of a rigid body such as synthetic resin or metal, or may be made of an elastic body such as rubber.

[0115] <Wearing method 2> 37A to 37C are used to illustrate the wearing method 2. As illustrated in Fig. 37A to 37C, the acoustic signal output device 2100' of the wearing method 2 is obtained by adding a wearing part 2123 (second wearing part) configured to be worn on a lower part 1024 (second auricle part) that is a part of the auricle 1020 different from the upper part 1022 (first auricle part) and the middle part 1023 (second auricle part) of the auricle 1020 to the acoustic signal output device 2100 of the wearing method 1.

[0116] The mounting part 2123 (second mounting part) in this example has a fixing part 2123a (second fixing part) that grips an end of the lower part 1024 (second auricle part) of the auricle 1020, and a support part 2123b that fixes the fixing part 2123a (second fixing part) to the housing 2112. One end of the support part 2123b holds a specific area of ​​the outer wall part of the fixing part 2123a, and the other end of the support part 2123b holds a specific area H3 (second holding area) of the outer wall part of the housing 2112. The area H3 is different from the above-mentioned areas H1 and H2. One end of the support part 2123b may be fixed to a specific area of ​​the wall part of the fixing part 2123a, or may be integrated with the wall part of the fixing part 2123a at the specific area. Similarly, the other end of the support part 2123b may be fixed to a specific region H3 of the outer wall of the housing 2112, or may be integrated with the outer wall of the housing 2112 at the specific region H3. In this way, the support part 2123b holds the housing 2112 from the outer side (second outer side different from the first outer side) of the specific region H3 of the wall of the housing 2112. In this example, when the fixing part 2123a is attached to the end of the lower part 1024 of the auricle 1020, the outer side (second outer side) of the region H3 becomes the lower part 1024 side of the auricle 1020. In this way, the housing 2112 is further held by the attachment part 2123 (second attachment part) from the outer side (second outer side different from the first outer side) of the region H3 to the lower part 1024 of the auricle 1020. This further stabilizes the position of the housing 2112 attached to the auricle 1020. Furthermore, the housing 2112 is held at different parts of the auricle 1020 (upper part 1022, middle part 1023, and lower part 1024) by the mounting part 2121 (first mounting part), the mounting part 2122 (second mounting part), and the mounting part 2123 (second mounting part), so that the burden on the auricle 1020 caused by wearing it can be distributed. Furthermore, the housing 2112 is attached to the auricle 1020 by the mounting parts 2121, 2122, and 2123 that grip the end of the auricle 1020. Such mounting parts 2121, 2122, and 2123 do not interfere with the temples of glasses or the string of a mask that are hooked on the back side of the auricle 1020. Note that the specific shape of the fixing part 2123a may be any shape.An example of the fixing part 2123a is a member having a hollow shape with a C-shape or U-shape in cross section, and configured to grip the lower part 1024 of the auricle 1020 with the inner wall surface 2123aa in contact with the helix 1022a. For example, the fixing part 2123a having an ear cuff shape can be exemplified. There is no limitation on the material constituting the wearing part 2123.

[0117] <Wearing method 3> The mounting section 2122 of the acoustic signal output device 2100' of the mounting method 2 may be omitted.

[0118] <Wearing method 4> As in the audio signal output device 2200 illustrated in FIG. 38, the mounting unit 2121 of the audio signal output device 2100 of the wearing method 1 may be replaced with a mounting unit 2224 of a type that is hooked on the back side of the upper part 1022 of the auricle 1020 (a type like an eyeglass temple). The mounting unit 2224 is a rod-shaped member. One end of the mounting unit 2224 is bent so as to be hooked on the back side of the upper part 1022 of the auricle 1020, and the other end holds a specific region H1 (first holding region) of the outer wall of the housing 2112. The other end of the mounting unit 2224 may be fixed to the specific region H1 of the outer wall of the housing 2112, or may be integrated with the outer wall of the housing 2112 at the specific region H1. Similarly, the mounting part 2121 of the acoustic signal output device 2100′ of the mounting methods 2 and 3 may be replaced with a mounting part 2224 of a type that is hooked onto the back side of the upper part 1022 of the auricle 1020. There is no limitation on the material that constitutes the mounting part 2224.

[0119] <Wearing method 5> 39A, the wearing part 2122 of the sound signal output device 2100 of the wearing method 1 may be replaced with a wearing part 2124 (second wearing part) that clamps an end of the middle part 1023 (second auricle part) of the auricle 1020. The wearing part 2124 (second wearing part) has a fixing part 2124a (second fixing part) that clamps an end of the middle part 1023 (second auricle part) of the auricle 1020, and a supporting part 2124b that fixes the fixing part 2124a (second fixing part) to the housing 2112. One end of the supporting part 2124b holds an end of the fixing part 2124a, and the other end of the supporting part 2124b holds a specific area H2 (second holding area) of the outer wall of the housing 2112. One end of the support portion 2124b may be fixed to an end of the fixed portion 2124a, or may be integrated with the end of the fixed portion 2124a. Similarly, the other end of the support portion 2124b may be fixed to a specific region H2 of the outer wall portion of the housing 2112, or may be integrated with the outer wall portion of the housing 2112 at the specific region H2. In this way, the support portion 2124b holds the housing 2112 from the outer side (a second outer side different from the first outer side) of the specific region H2 of the wall portion of the housing 2112. In this manner, the housing 2112 is held by the mounting part 2121 (first mounting part) at the upper part 1022 of the auricle 1020 from the outer side (first outer side) of the region H1 as described above, and is further held by the mounting part 2124 (second mounting part) at the middle part 1023 of the auricle 1020 from the outer side (second outer side different from the first outer side) of the region H2. This stabilizes the position of the housing 2112 mounted on the auricle 1020. In this case as well, the housing 2112 is held by the mounting part 2121 (first mounting part) and the mounting part 2124 (second mounting part) at different parts (upper part 1022 and middle part 1023) of the auricle 1020, so that the burden on the auricle 1020 caused by mounting can be distributed. Furthermore, the attachment parts 2121, 2124 do not interfere with the temples of glasses or the string of a mask that are hooked on the back side of the auricle 1020. Alternatively, the clamping fixing part 2124a (second fixing part) may be configured to clamp the lower part 1024 of the auricle 1020 instead of the middle part 1023 of the auricle 1020. The specific shape of the fixing part 2124a may be any shape.For example, the fixing portion 2124a may be a clip-like clamping mechanism or an integrated leaf spring. In addition, the material from which the mounting portion 2124 is made is not limited.

[0120] <Wearing method 6> 39B, the mounting part 2121 of the acoustic signal output device 2300 of the wearing method 5 may be replaced with a mounting part 2224 of a type that is hooked onto the back side of the upper part 1022 of the auricle 1020. The configuration of the mounting part 2224 is the same as that of the wearing method 4.

[0121] <Wearing method 7> When the housing 2112 is the housing 12, 12'', 22 exemplified in the first to fourth embodiments and their modified examples, the opening area of ​​the sound holes 123a, 223a (second sound hole) provided in or near the area (shielded area) where the acoustic signal AC1 (first acoustic signal) emitted from the sound holes 121a, 221a (first sound hole) of the housings 12, 12'', 22 is blocked by the mounting parts 2121, 2122, 2123, 2124, 2224 may be made smaller than the opening area of ​​the sound holes 123a, 223a (second sound hole) provided at a position away from the shielded area. As described above, a part of the acoustic signal AC1 (first acoustic signal) emitted from the sound holes 121a, 221a (first sound hole) of the housings 12, 12″, 22 is cancelled out by the acoustic signal AC2 (second acoustic signal) emitted from the sound holes 123a, 223a (second sound hole), thereby suppressing sound leakage. Here, the sound pressure of the acoustic signal AC1 (first acoustic signal) leaking to the outside is smaller in the shielded area than in other areas. Accordingly, by reducing the opening area of ​​the sound holes 123a, 223a (second sound hole) provided in or near the shielded area, the sound pressure of the acoustic signal AC1 (first acoustic signal) leaking to the outside can be reduced. This makes it possible to achieve a balance between the distribution of sound pressure of the acoustic signal AC1 (first acoustic signal) leaking into the sound hole 123a and the distribution of sound pressure of the acoustic signal AC2 (second acoustic signal) emitted from the sound holes 123a and 223a (second sound holes). That is, the acoustic signal AC1 (first acoustic signal) is emitted from the sound holes 121a and 221a (first sound holes), and the acoustic signal AC2 (second acoustic signal) is emitted from the sound holes 123a and 223a (second sound holes). In this case, the attenuation rate η of the acoustic signal AC1 (first acoustic signal) at position P2 (second point) based on position P1 (first point) is 11 is the attenuation rate of the acoustic signal due to air propagation at position P2 (second point) relative to position P1 (first point), η 21 A predetermined value η smaller than th The sound pressure distribution can be balanced as follows: In this case, 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) is: 12 is the attenuation of the acoustic signal due to air propagation at position P2 (second point) relative to position P1 (first point), η 22 A predetermined value ω greater than thAs described above, the sound pressure distribution can be balanced. Note that position P1 (first point) here is a predetermined point reached by the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 221a (first sound hole). Position P2 (second point) here is a predetermined point that is farther away from the acoustic signal output device than position P1 (first point). As a result, sound leakage can be effectively suppressed.

[0122] Below, an example will be described in which the housing 2112 is the housing 12 of the first embodiment or its modified example, and this housing 12 (housing 2112) is held in the mounting parts 2121, 2122 of mounting method 1. However, this does not limit the present invention. The housing 2112 may be the housings 12, 12'', 22 exemplified in the second to fourth embodiments and their modified examples, or this housing 12, 12'', 22 may be held in the mounting parts 2121, 2122, 2123, 2124, 2224 of any of mounting methods 2 to 6. In this case as well, the following configuration can be applied.

[0123] 40A, the acoustic signal output device 2100 in this case has a driver unit 11 that emits an acoustic signal AC1 (first acoustic signal) to one side (D1 direction side) and emits an acoustic signal AC2 (second acoustic signal) that is an inverse phase signal of the acoustic signal AC1 (first acoustic signal) or an approximate signal of the inverse phase signal to the other side (D2 direction side). As described above, the walls 121 and 123 of the housing 12 are provided with one or more sound holes 121a (first sound holes) that lead out the acoustic signal AC1 (first acoustic signal) emitted from the driver unit 11 to the outside, and one or more sound holes 123a (second sound holes) that lead out the acoustic signal AC2 (second acoustic signal) emitted from the driver unit 11 to the outside. As described above, a part of the acoustic signal AC2 (second acoustic signal) emitted from the sound hole 123a (second sound hole) cancels a part of the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole), thereby suppressing sound leakage. As described above, the support part 2121b of the mounting part 2121 (first mounting part) holds the area H1 (first holding area) of the wall part 123 of the housing 12 (housing 2112), and the support part 2122b of the mounting part 2122 (second mounting part) holds the area H2 (second holding area) of the wall part 123 of the housing 12 (housing 2112). Here, the sound hole 121a (first sound hole) is disposed on one side (D1 direction side) of the space partitioned by the imaginary plane P51 passing through the area H1 (first holding area) and the mounting part 2122 (second mounting part). On the other hand, the sound hole 123a (second sound hole) is arranged on the other side (D2 direction side) of the space partitioned by the imaginary plane P51. Here, the opening area of ​​the sound hole 123a (second sound hole) provided in or near the shielded area AR51 where the acoustic signal AC1 (first acoustic signal) is shielded by the support part 2121b of the mounting part 2121 (first mounting part) or the support part 2122b of the mounting part 2122 (second mounting part) is made small. That is, as illustrated in FIG. 40B, the sound hole 123a (second sound hole) is provided along the above-mentioned circumference C1. Also, it is assumed that the surface of the wall part 123 of the housing 12 is equally divided into a plurality of unit area areas (unit area areas C5-1, C5-2, C5-3, C5-4 in this example) along the circumference C1.In this example, the number of sound holes 123a (second sound holes) provided in the first unit area area (unit area areas C5-2 and C5-3 in this example) which is one of the unit area areas including the shielded area AR51 is smaller than the number of sound holes 123a (second sound holes) provided in the second unit area area (unit area areas C5-1 and C5-4 in this example) which is one of the unit area areas not including the shielded area AR51. In this case, the sum of the opening areas of the sound holes 123a (second sound holes) provided in the first unit area area (unit area areas C5-2 and C5-3 in this example) which is one of the unit area areas including the shielded area AR51 is smaller than the sum of the opening areas of the sound holes 123a (second sound holes) provided in the second unit area area (unit area areas C5-1 and C5-4 in this example) which is one of the unit area areas not including the shielded area AR51. This makes it possible to effectively suppress sound leakage.

[0124] 41A and 41B, the number of sound holes 123a (second sound holes) provided in a first unit area area (unit area areas C5-2 and C5-3 in this example) including the shielded area AR51 may be less than the number of sound holes 123a (second sound holes) provided in a second unit area area (unit area areas C5-1 and C5-4 in this example) not including the shielded area AR51, and further, sound holes 123a having a larger opening area than the first unit area may be provided in the second unit area area. Alternatively, the number of sound holes 123a may be equal in the first unit area area and the second unit area area, and the opening area of ​​each sound hole 123a provided in the first unit area area may be smaller than the opening area of ​​each sound hole 123a provided in the second unit area area. Even in such a case, the sum of the opening areas of the sound holes 123a (second sound holes) provided in the first unit area area (unit area areas C5-2 and C5-3 in this example) is smaller than the sum of the opening areas of the sound holes 123a (second sound holes) provided in the second unit area area (unit area areas C5-1 and C5-4 in this example). Even in this case, sound leakage can be effectively suppressed.

[0125] <Wearing method 8> 42, 43A, and 43B are used to illustrate the wearing method 8. As illustrated in Fig. 42 and 43A, an acoustic signal output device 2500 of the wearing method 8 has a housing 2112 that emits an acoustic signal, and a wearing part 2221 that holds the housing 2112 and is configured to be worn on the auricle 1020.

[0126] The mounting part 2221 includes a fixed part 2221a having a concave inner wall surface 2221aa configured to be fitted into the upper part 1022 of the auricle 1020, and a shielding wall 2221b configured to cover only a part of the auricle 1020 when the inner wall surface 2221aa side of the fixed part 2221a is fitted into the upper part 1022 of the auricle 1020. The fixed part 2221a in this example has a hollow structure that accommodates at least a part of the upper part 1022 of the auricle 1020 (e.g., the helix 1022a). Considering the burden on the auricle 1020, it is desirable that the inner wall surface 2221aa of the fixed part 2221a is 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 in this example is configured to have a shape that covers the upper part 1022 of the auricle 1020 while opening the lower part 1024 of the auricle 1020 to the outside when the inner wall surface 2221aa side of the fixing part 2221a is fitted into the upper part 1022 of the auricle 1020. That is, the end 2221c (the end opposite to the fixing part 2221a) side of the shielding wall 2221b is an opening part O51. The opening part O51 is provided at a position that opens the lower part 1024 of the auricle 1020 to the outside when the upper part 1022 of the auricle 1020 is fitted into the inner wall surface 2221aa side of the fixing part 2221a. There is no limitation on the material that constitutes the mounting part 2221.

[0127] The housing 2112 in this example may be any of the housings 12, 12", 22 exemplified in the first to fourth embodiments and their modified examples, or may be a housing of a conventional audio signal output device that emits an audio signal, such as an earphone. The housing 2112 is held on the inner wall surface 2221bb side of the shielding wall 2221b, and a sound hole 2112a that emits an audio signal opens in the direction opposite to the inner wall surface 2221bb. When the audio signal output device 2500 is attached to 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 auricle 1020). The shielding wall 2221b is disposed so that the shielding wall 2221b faces the ear canal 1020 side, the sound hole 2112a of the housing 2112 held on the inner wall surface 2221bb faces the ear canal 1021 side, and the housing 2112 does not block the ear canal 1021. At this time, since the sound hole 2112a is disposed on the inside side of the shielding wall 2221b, the influence of external noise is suppressed and sound leakage of the acoustic signal emitted from the sound hole 2112a can also be suppressed. Furthermore, since the shielding wall 2221b covers only a portion of the pinna 1020 (the lower part 1024 side of the pinna 1020 is not blocked), external sounds are not completely blocked and the user can also hear external sounds.

[0128] <Wearing method 9> 44, an acoustic signal output device 2500' of wearing method 9 is a modified example of the acoustic signal output device 2500 of wearing method 8, in which the wearing section 2221 of the acoustic signal output device 2500 is replaced with a wearing section 2221'. In the wearing section 2221', the shielding wall 2221b of the wearing section 2221 is replaced with a shielding wall 2221b'. The shielding wall 2221b' is configured in a shape such that when the inner wall surface 2221aa side of the fixing section 2221a is fitted into the upper section 1022 of the auricle 1020, a part of the upper section 1022 of the auricle 1020 is further opened to the outside. That is, the end 2221c (end opposite the fixed part 2221a) of the shielding wall 2221b' is an opening O51, and further, a part of the shielding wall 2221b' on the fixed part 2221a side is also an opening O52 (through hole). The opening O52 is provided at a position that opens a part of the upper part 1022 of the auricle 1020 to the outside. The rest is the same as in wearing method 8. Since the shielding wall 2221b' covers only a part of the auricle 1020 (the lower part 1024 side and a part of the upper part 1022 side of the auricle 1020 are not blocked), external sounds are not completely blocked, and the user can also hear external sounds.

[0129] <Wearing method 10> When the housing 2112 is the housing 12, 12", 22 exemplified in the first to fourth embodiments and their modified examples, it is desirable that the sound holes 121a, 221a (first sound hole) of the housings 12, 12", 22 are arranged on the inner side of the shielding wall 2221b, and the sound holes 123a, 223a (second sound hole) are arranged on the outer side of the shielding wall 2221b. This makes it possible to cancel out a part of the acoustic signal AC1 (first acoustic signal) leaking outward from the shielding wall 2221b with a part of the acoustic signal AC2 emitted from the sound holes 123a, 223a (second sound hole), while suppressing the acoustic signal AC1 from being cancelled out by the acoustic signal AC2 on the inner side of the shielding wall 2221b. As a result, it is possible to effectively suppress sound leakage of the acoustic signal AC1 to the outside without significantly reducing the hearing efficiency of the acoustic signal AC1 by the user.

[0130] In this case, the sound pressure of the acoustic signal AC1 leaking out from the openings O51, O52 of the shielding walls 2221b, 2221b' is larger than the sound pressure of the acoustic signal AC1 leaking out from the shielding walls 2221b, 2221b' other than the openings O51, O52. Therefore, it is preferable that the opening area per unit area of ​​the sound holes 123a, 223a (second sound holes) arranged on the side where the openings O51, O52 are provided is larger than the opening area per unit area of ​​the sound holes 123a, 223a (second sound holes) arranged on the side where the openings O51, O52 are not provided. This makes it possible to bring the distribution of the sound pressure of the acoustic signal AC2 (second acoustic signal) emitted from the sound holes 123a, 223a (second sound holes) closer to the distribution of the sound pressure of the acoustic signal AC1 leaking out of the shielding wall 2221b, and the acoustic signal AC1 can be appropriately cancelled out by the acoustic signal AC2. That is, an acoustic signal AC1 (first acoustic signal) is emitted from the sound holes 121a and 221a (first sound holes), and an acoustic signal AC2 (second acoustic signal) is emitted from the sound holes 123a and 223a (second sound holes). In this case, 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) is 11 is the attenuation rate of the acoustic signal due to air propagation at position P2 (second point) relative to position P1 (first point), η 21 A predetermined value η smaller than th The sound pressure distribution can be balanced as follows: In this case, 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) is: 12 is the attenuation of the acoustic signal due to air propagation at position P2 (second point) relative to position P1 (first point), η 22 A predetermined value ω greater than th As described above, the sound pressure distribution can be balanced. Note that position P1 (first point) here is a predetermined point reached by the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 221a (first sound hole). Position P2 (second point) here is a predetermined point that is farther away from the acoustic signal output device than position P1 (first point). This makes it possible to effectively suppress sound leakage.

[0131] Below, an example will be described in which the housing 2112 is the housing 12 of the first embodiment or its modified example, and this housing 12 (housing 2112) is held in a mounting section 2221 of mounting method 8. However, this does not limit the present invention. The housing 2112 may be the housings 12, 12'', 22 exemplified in the second to fourth embodiments and their modified examples, or the housings 12, 12'', 22 may be held in a mounting section 2221' of mounting method 9. In this case as well, the following configuration can be applied.

[0132] As illustrated in Fig. 46B, the acoustic signal output device 2600 in this case has a driver unit 11 that emits an acoustic signal AC1 (first acoustic signal) to one side (D1 direction side) and emits an acoustic signal AC2 (second acoustic signal) that is an inverse phase signal of the acoustic signal AC1 (first acoustic signal) or an approximate signal of the inverse phase signal to the other side (D2 direction side). As described above, the walls 121 and 123 of the housing 12 are provided with one or more sound holes 121a (first sound holes) that lead out the acoustic signal AC1 (first acoustic signal) emitted from the driver unit 11 to the outside, and one or more sound holes 123a (second sound holes) that lead out the acoustic signal AC2 (second acoustic signal) emitted from the driver unit 11 to the outside (Figs. 46B and 46C). As described above, a part of the acoustic signal AC2 (second acoustic signal) emitted from the sound hole 123a (second sound hole) cancels a part of the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole), thereby suppressing sound leakage. As illustrated in FIG. 46B, 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. This makes it possible to cancel a part of the acoustic signal AC1 (first acoustic signal) leaking to the outer side of the shielding wall 2221b with a part of the acoustic signal AC2 emitted from the sound hole 123a (second sound hole), while suppressing the acoustic signal AC1 from being canceled by the acoustic signal AC2 on the inner side of the shielding wall 2221b. As a result, sound leakage of the acoustic signal AC1 to the outside can be effectively suppressed without significantly reducing the efficiency with which the user can hear the acoustic signal AC1.

[0133] As described above, an opening O51 is provided in a part of the shielding wall 2221b (on the end 2221c side) that partially opens a part of the pinna 1020 (lower part 1024) to the outside when the upper part 1022 of the pinna 1020 is fitted to the inner wall surface 2221aa side of the fixed part 2221a (FIGS. 46A and 46B). That is, the opening O51 in this example is provided at a position that opens the lower part 1024 of the pinna 1020 to the outside when the upper part 1022 of the pinna 1020 is fitted to the inner wall surface 2221aa side of the fixed part 2221a. Here, the opening area per unit area of ​​the sound hole 123a (second sound hole) arranged on the side where the opening O51 is provided (FIG. 46B) is larger than the opening area per unit area of ​​the sound hole 123a (second sound hole) arranged on the side where the opening is not provided (FIG. 46C). That is, as illustrated in FIG. 46B, FIG. 46C, and FIG. 47A, the sound holes 123a (second sound holes) are provided along the above-mentioned circumference C1. Here, it is assumed that the surface of the wall portion 123 of the housing 12 is equally divided into unit area areas (unit area areas C5-1, C5-2 in this example) along the circumference C1. In this example, the number of the sound holes 123a (second sound holes) arranged on the side where the open portion O51 is provided (unit area area C5-1) is greater than the number of the sound holes 123a (second sound holes) arranged on the side where the open portion is not provided (unit area area C5-2). Therefore, the opening area per unit area of ​​the sound holes 123a (second sound holes) arranged on the side where the open portion O51 is provided (unit area area 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 open portion is not provided (unit area area C5-2). This allows the sound pressure distribution of acoustic signal AC2 (second acoustic signal) emitted from sound holes 123a, 223a (second sound hole) to be made closer to the sound pressure distribution of acoustic signal AC1 leaking out of shielding wall 2221b, and allows acoustic signal AC1 to be appropriately offset by acoustic signal AC2, effectively suppressing sound leakage.

[0134] Alternatively, as illustrated in Fig. 47B, the average value of the opening area of ​​the sound holes 123a (second sound holes) arranged on the side where the open portion O51 is provided (unit area area C5-1) may be larger than the average value of the opening area of ​​the sound holes 123a (second sound holes) arranged on the side where the open portion O51 is provided (unit area area C5-2). Alternatively, as illustrated in Fig. 48A, the sound holes 123a (second sound holes) arranged in pairs in a direction perpendicular to the circumference C1 may be arranged at equal intervals in the circumference C1 direction on the side where the open portion O51 is provided (unit area area C5-1), and one sound hole 123a (second sound hole) may be arranged at equal intervals in the circumference C1 direction on the side where the open portion is not provided (unit area area C5-2). 48B, the sound hole 123a (second sound hole) may be arranged on the side where the open portion O51 is provided (unit area C5-1), but the sound hole 123a (second sound hole) may not be arranged on the side where the open portion is not provided (unit area C5-2). Even in this case, sound leakage can be effectively suppressed.

[0135] [Sixth embodiment] In the sixth embodiment, another wearing method of an ear-mounted acoustic signal output device will be illustrated.

[0136] <Wearing method 11> As in the acoustic signal output device 3100 illustrated in FIG. 49A, the mounting section 2121 of the acoustic signal output device 2100 of the wearing method 1 may be omitted.

[0137] <Wearing method 12> As in the acoustic signal output device 3200 illustrated in FIG. 49B, the mounting section 2123 of the acoustic signal output device 2100 of wearing method 1 may be omitted, and the housing 2112 may be any of the housings 12, 12”, 22 described above. However, in this example, when the acoustic signal output device 3200 is worn on the auricle 1020, the opening direction (D1) of the sound holes 121a, 221a of the housings 12, 12”, 22 is configured to be approximately perpendicular to the direction of the external auditory canal 1021.

[0138] <Wearing method 13> As in the acoustic signal output device 3300 illustrated in FIG. 50A, the mounting section 2121 of the acoustic signal output device 2300 of wearing method 5 may be omitted, and the housing 2112 may be any of the housings 12, 12”, and 22 described above. In this example, when the acoustic signal output device 3300 is worn on the auricle 1020, the sound holes 121a, 221a of the housings 12, 12”, and 22 are configured to face the ear canal 1021 side.

[0139] <Wearing method 14> 50B, the mounting unit 2221 of the audio signal output device 2500 of the wearing method 8 may be replaced with a mounting unit 2221'. The mounting unit 2221' includes a shielding wall 2221b configured to cover only the upper part 1022 of the auricle 1020 when the inner wall surface side of the fixing part 2221a is fitted into the upper part 1022 of the auricle 1020. In addition, an end 2221c' of the shielding wall 2221b is configured in a curved shape, 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 base side of the auricle 1020.

[0140] <Wearing method 15> As in the acoustic signal output device 4100 illustrated in FIG. 51A, the mounting section 2122 of the acoustic signal output device 2200 of the mounting method 4 may be omitted.

[0141] <Wearing method 16> 51B, the mounting unit 2122 of the acoustic signal output device 2200 of the wearing method 4 may be omitted, and a mounting unit 4421 configured to contact the cavity of the concha 1025 of the auricle 1020 when worn may be provided. One end of the mounting unit 4421 holds the housing 2112, and the other end of the mounting unit 4421 is configured to have a shape capable of supporting the cavity of the concha 1025 so as not to block the ear canal. This allows for more stable wearing.

[0142] <Wearing method 17> The acoustic signal output device 4200 illustrated in FIG. 52A has a housing 2112, a columnar mounting portion 4210 that holds the housing 2112 and is configured to be positioned at the base of the auricle 1020 when worn, and an arc-shaped mounting portion 4220 that is held at both ends of the mounting 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.

[0143] <Wearing method 18> As in the acoustic signal output device 4300 illustrated in FIG. 52B, the mounting section 2122 of the acoustic signal output device 2200 of wearing method 4 may be omitted, and the housing 2112 may be any of the housings 12, 12”, and 22 described above. However, in this example, when the acoustic signal output device 4300 is worn on the auricle 1020, the opening direction (D1) of the sound holes 121a, 221a of the housings 12, 12”, and 22 is configured to be approximately perpendicular to the direction of the external auditory canal 1021.

[0144] <Wearing method 19> The acoustic signal output device 5110 of the wearing method 19 illustrated in FIG. 53A to FIG. 53E has a housing 5111 that emits an acoustic signal, and a wearing part 5112 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 bent rod-shaped member, and the housing 5111 is attached to one end of the housing 5111 so as to be rotatable in the R5 direction. As illustrated in FIG. 53E, the housing 5111 is worn in a state where the sound hole from which the acoustic signal is emitted faces the ear canal without blocking the ear canal. At this time, the auricle 1020 is sandwiched between the housing 5111 and the wearing part 5112, and the acoustic signal output device 5110 is fixed to the auricle 1020. In addition, since the housing 5111 can be rotated in the R5 direction relative to one end of the wearing part 5112, the wearing position and the position of the sound hole can be adjusted according to the size and shape of each individual auricle 1020.

[0145] <Wearing method 20> The acoustic signal output device 5120 of the wearing method 20 illustrated in Fig. 54A to Fig. 54C has a housing 5121 that emits an acoustic signal, and a mounting part 5122 that holds the housing 5121 and is hooked on the back side of the upper part 1022 of the auricle 1020 when worn. Unlike the wearing method 19, the housing 5121 is not rotatable to the mounting part 5122. As illustrated in Fig. 54C, the housing 5121 is worn in a state where the sound hole from which the acoustic signal is emitted faces the ear canal without blocking the ear canal. At this time, the auricle 1020 is sandwiched between the housing 5121 and the mounting part 5122, and the acoustic signal output device 5120 is fixed to the auricle 1020.

[0146] <Wearing method 21> The acoustic signal output devices 5130, 5140 of the wearing method 21 illustrated in Fig. 55A and Fig. 55B each have a housing 5131, 5141 that emits an acoustic signal, and a wearing part 5132, 5142 that holds the housing 5131, 5141 and is hooked onto the back side of the upper part 1022 of the auricle 1020 when worn. Furthermore, the acoustic signal output device 5140 illustrated in Fig. 55B is provided with a wearing part 5143 that is configured to come into contact with the concha cavity 1025 of the auricle 1020 when worn. This allows for more stable wearing.

[0147] <Wearing method 22> An acoustic signal output device 5150 illustrated in FIGS. 56A, 56B, and 56C includes a housing 5151 that emits an acoustic signal, a rod-shaped mounting part 5152 that holds the housing 5151 and is hooked onto the back side of the upper part 1022 of the auricle 1020 when worn, a column-shaped support part 5154 that holds the housing 5151 at one end and the mounting part 5152 at the other end, and a support part 5154 that supports the housing 5151 at one end and the mounting part 5152 at the other end. 0The housing 5151 has a rod-shaped mounting part 5153 that can be hooked from the middle part 1023 side to the back side of the middle part 1023 and the upper part 1022, and a columnar support part 5155 that holds the housing 5151 at one end and the mounting part 5153 at the other end. As shown in Fig. 56C, the housing 5151 is mounted without blocking the ear canal, with the sound hole from which the acoustic signal is emitted facing the ear canal. At this time, the auricle 1020 is sandwiched between the housing 5151 and the mounting parts 5152, 5153, and the acoustic signal output device 5150 is fixed to the auricle 1020.

[0148] <Wearing method 23> The acoustic signal output device 5160 illustrated in Fig. 57A to Fig. 57E includes a housing 5161 that emits an acoustic signal, a columnar mounting part 5164 that holds the housing 5161 and is configured to be placed at the base of the auricle 1020 when worn, a rod-shaped mounting part 5162 that is held at one end of the mounting part 5164 and is hooked on the back side of the upper part 1022 of the auricle 1020 when worn, and a rod-shaped mounting part 5163 that is held at the other end of the mounting part 5164 and is hooked on the back side of the lower part 1024 of the auricle 1020 when worn. As illustrated in Fig. 57E, the housing 5161 is worn with the sound hole from which the acoustic signal is emitted facing the ear canal without blocking the ear canal. At this time, the auricle 1020 is in contact with the housing 5161, the mounting part 5164, and the mounting part 5162. 5162,5163 , whereby the acoustic signal output device 5160 is fixed to the auricle 1020.

[0149] <Wearing method 24> Acoustic signal output devices 5170 and 5180 illustrated in FIGS. 58A to 58D and 59A to 59D each include housings 5171 and 5181 that emit acoustic signals, and Listen 102 0The housings 5171, 5181 are attached to the ear canal with the sound hole for emitting the acoustic signal facing the ear canal side without blocking the ear canal. At this time, the auricle 1020 is sandwiched between the housings 5171, 5181 and the attachment parts 5172, 5182, and the acoustic signal output device 5170, 5180 is fixed to the auricle 1020.

[0150] <Wearing method 25> The acoustic signal output device 5190 illustrated in FIG. 60A to FIG. 60C includes a housing 5191 that emits an acoustic signal, and the housing 5191 is held by the housing 5191. When the housing 5191 is worn, the housing 5191 is in contact with the auricle 102. 0 and a rod-shaped mounting part 5192 configured to be arranged on the back side of the auricle 1020. The mounting part 5192 holds the housing 5191 at one end that is arranged on the lower part 1024 side of the auricle 1020 when mounted. As illustrated in Fig. 60C, the housing 5191 is mounted in a state in which the sound hole from which the acoustic signal is emitted faces the ear canal without blocking the ear canal. At this time, the auricle 1020 is sandwiched between the housing 5191 and the mounting part 5192, whereby the acoustic signal output device 5190 is fixed to the auricle 1020.

[0151] <Wearing method 26> The acoustic signal output device 5200 illustrated in Fig. 61A to Fig. 61E includes a housing 5201 that emits an acoustic signal, and an annular mounting part 5202 that holds a housing 5021. As illustrated in Fig. 61E, the housing 5201 is mounted in a state in which the sound hole from which the acoustic signal is emitted faces the ear canal without blocking the ear canal. When mounted, the auricle 1020 is inserted into the annular mounting part 5202, and the mounting part 5202 is disposed 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 mounting part 5202, whereby the acoustic signal output device 5200 is fixed to the auricle 1020.

[0152] <Wearing method 27> As illustrated in Figures 62A and 64B, the acoustic signal output device may be of a type in which any of the housings 12, 12'', 22 exemplified in the first to fourth embodiments and their modified examples is fixed to the temples of glasses.

[0153] In the acoustic signal output devices 5310 and 5320 illustrated in Fig. 62A and Fig. 62B, one end of a support part 5312 is held in a middle part of a temple 5311, and the other end of the support part 5312 holds a housing 12. In both acoustic signal output devices 5310 and 5320, the temple 5311 is disposed on the back side of the upper part 1022 of the auricle 1020 when worn. However, in the acoustic signal output device 5310 illustrated in Fig. 62A, the opening direction of the sound hole 121a of the housing 12 is inclined with respect to the ear canal 1021 when worn. On the other hand, in the example of the acoustic signal output device 5320 illustrated in Fig. 62B, the sound hole 121a of the housing 12 is disposed toward the ear canal 1021 when worn.

[0154] Figure 63A and Figure 6 3 In the acoustic signal output devices 5340 and 5350 illustrated in FIG. 63B, the housing 12 is held directly at the middle part of the temple 5311. In both acoustic signal output devices 5340 and 5350, the temple 5311 is disposed on the back side of the upper part 1022 of the auricle 1020 when worn. However, in the acoustic signal output device 5340 illustrated in FIG. 63A, the housing 12 is held by the temple 5311 so that the opening direction of the sound hole 121a of the housing 12 is approximately perpendicular to the temple 5311, and is disposed so that the opening direction of the sound hole 121a of the housing 12 is approximately perpendicular to the ear canal 1021 when worn. On the other hand, in the acoustic signal output device 5350 illustrated in FIG. 63B, the housing 12 is held by the temple 5311 so that the opening direction of the sound hole 121a of the housing 12 is approximately parallel to the temple 5311, and when worn, the housing 12 is positioned so that the opening direction of the sound hole 121a of the housing 12 faces the upper part 1022 of the auricle 1020.

[0155] 64A and 64B, the housing 12 is held directly by the tips of the temples 5361, 5371. In both of the acoustic signal output devices 5360, 5370, the temples 5361 are disposed on the back side of the upper part 1022 of the pinna 1020 when worn. However, in the acoustic signal output device 5360 shown in FIG. 64A, the opening direction of the sound hole 121a of the housing 12 is oriented from the base side of the lower part 1024 of the pinna 1020 toward the ear canal 1022 when worn. 21 64B, the sound signal output device 5370 is disposed so that the opening direction of the sound hole 121a of the housing 12 is directed from the outside of the lower part 1024 of the auricle 1020 to the ear canal 10. 21 It is positioned so that it faces the side.

[0156] <Wearing method 28> Alternatively, as in an acoustic signal output device 5380 illustrated in FIG. 65A, any of the housings 12, 12'', and 22 illustrated in the first to fourth embodiments and their modified examples may be fixed to a rod-shaped mounting part 5381 curved into a shape so as to be worn on the neck or shoulders of the user 1000. Also, as in an acoustic signal output device 5390 illustrated in FIG. 65B, any of the housings 12, 12'', and 22 may be fixed to a rod-shaped mounting part 5391 curved into a shape so as to be worn on the top of the head of the user 1000. Also, as in an acoustic signal output device 5400 illustrated in FIG. 65C, 1000 Either the housing 12, 12'', or 22 may be fixed to a rod-shaped mounting portion 5401 that is curved into a shape that allows it to be mounted on the back of the head and the auricle 1020 of the user.

[0157] <Other mounting methods> In addition, the existing open-ear type earphone wearing method may be applied to the acoustic signal output devices 4, 4', 10, 20, 30 exemplified in the first to fourth embodiments and their modified examples. For example, as exemplified in Reference Document 1 (https: / / www.sony.jp / headphone / products / STH40D / feature_1.html), a ring body serving as a stopper may be added to the D1 direction side of the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2, and a U-shaped wearing part may be added to the side opposite the D1 direction of the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2. In this case, the ring-shaped attachment part is placed around the external auditory canal (e.g., the concha) and the lower part of the auricle is clamped by the U-shaped attachment part, thereby attaching the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 to the auricle. In particular, when applying the attachment method of Reference Document 1 to the acoustic signal output device 20 of the second embodiment, a ring-shaped attachment part acting as a stopper can be added to the D1 direction side of the housing 22, and the U-shaped attachment part added to the D2 direction side of the housing 22 can be configured to serve as both the waveguides 24, 25 and the housing 23 (Figure 20).

[0158] 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 housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 may be formed into a substantially elliptical cylindrical shape, and a J-shaped attachment unit may be provided on the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2. In this case, the D1 direction side of the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 is placed against the front side (external ear canal side) of the upper part of the auricle, and the J-shaped attachment unit is hooked onto the back side of the upper part of the auricle, whereby the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 are attached to the auricle.

[0159] For example, as illustrated in Reference 3 (https: / / ambie.co.jp / soundearcuffs / tws / ), the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 may be configured in a substantially spherical shape, and the side opposite the D1 direction of the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 may be held by one end of a C-shaped attachment part. The other end of this C-shaped attachment part may also be configured in a substantially spherical shape. In this case, the D1 direction side of the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 is placed against the periphery of the external ear canal (for example, the concha), and the C-shaped attachment part grips (sandwiches) the middle part of the concha, whereby the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 are attached to the concha.

[0160] For example, as illustrated in Reference 4 (https: / / www.jabra.jp / bluetooth-headsets / jabra-elite-active-45e##100-99040000-40), a sound tube may be added to the sound holes 121a, 221a of the housings 12, 12″, 22 or the sound signal output units 40-1, 40-2 to direct the sound signals emitted from the sound holes 121a, 221a to the external ear canal.

[0161] For example, as exemplified in Reference 5 (https: / / www.audio-technica.co.jp / product / ATH-EW9), a semicircular mounting portion (ear hanger) equipped with an adjustment mechanism (slide fit mechanism) for adjusting the position of the mounted housing 12, 12", 22 or acoustic signal output unit 40-1, 40-2 relative to the auricle may be provided. In this case, the D1 direction side of housing 12, 12", 22 or acoustic signal output unit 40-1, 40-2 is placed against the front side of the upper part of the auricle, and the semicircular mounting portion is hooked onto the back side of the upper part of the auricle, thereby mounting housing 12, 12", 22 or acoustic signal output unit 40-1, 40-2 to the auricle. By operating the adjustment mechanism in this state, the position of the mounted housing 12, 12", 22 or acoustic signal output unit 40-1, 40-2 relative to the auricle can be adjusted.

[0162] For example, as exemplified in Reference 6 (https: / / www.mu6.live / ), a headband-type wearing unit may be provided on the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2. For example, both ends of the headband-type wearing unit may hold the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2. In this case, the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 may be rotatable with respect to both ends of the headband-type wearing unit. In this case, the D1 direction side of the housings 12, 12", 22 or the acoustic signal output units 40-1, 40-2 is placed against the auricle or near the auricle, and the headband-type wearing unit is worn on the head. At this time, by rotating the housings 12, 12'', 22 or the acoustic signal output units 40-1, 40-2 relative to the headband-type mounting unit, the mounting position of the headband-type mounting unit and the positions of the housings 12, 12'', 22 or the acoustic signal output units 40-1, 40-2 relative to the auricle can be adjusted.

[0163] [Other modifications, etc.] The present invention is not limited to the above-mentioned embodiments. For example, in each of the above-mentioned embodiments and their modified examples, the present invention is applied to a device for listening to sound that is attached to the ear without sealing the ear canal of the user (for example, open-ear type earphones, headphones, etc.). However, this does not limit the present invention, and the present invention may be applied to a device for listening to sound that is attached to a body part other than the ear without sealing the ear canal of the user, such as a bone conduction earphone or a neck speaker earphone.

[0164] In addition, for example, the present invention may be used as an acoustic signal output device capable of controlling the attenuation rate of an acoustic signal emitted to the outside, even if a sound absorbing material is not provided in the sound hole through which the acoustic signal emitted from the driver unit passes. Also, for example, the present invention may be used as an acoustic signal output device capable of attenuating an acoustic signal emitted from a driver unit so that it cannot be heard at a predetermined position, even if directional control is not performed by physical shape or signal processing. Also, for example, the present invention may be used as an acoustic signal output device capable of attenuating an acoustic signal at a point where the acoustic signal is to be attenuated, even if a speaker is not placed at the point. Also, for example, the present invention may be used as an acoustic signal output device capable of locally reproducing an acoustic signal in a specific local area, even if the periphery of the specific local area is not covered with a sound absorbing material. [Explanation of symbols]

[0165] 4,4',10,20,30,2100-2600,3100-3300,3600,4100-4300,5110-5200,5310-5400 Acoustic signal output device 11 Driver unit 113 Diaphragm 12,12”,22,23,2112,5021,5111,5121,5131,5151,5161,5171,5191,5201 Housing 121a,123a,221a,223a sound hole 13 Sound absorbing material 24,25 Waveguide 31,41 Circuit section 40-1, 40-2 Audio signal output section AC1,AC2 acoustic signal AR21,AR22 hollow part C1 Circumference C1-1, C1-2, C1-3, C1-4 Unit arc area MAC1, MAC2 monaural audio signal 2121,2122,2123,2124,2221,2224,4210,4220,4421,5112,5122,5132,5152,5153,5162,5163,5164,5172,5192,5202,5381,5391,5401 Mounting part 2121a,2122a,2123a,2124a,2221a Fixed part 2221b Shielding Wall

Claims

1. An acoustic signal output device to be worn on an auricle, A housing that emits an acoustic signal; a mounting portion that holds the housing and is configured to be mounted on the auricle; The mounting portion includes a fixing portion having a concave inner wall surface configured to be fitted into an upper portion of the auricle, and a shielding wall configured to cover only a portion of the auricle when the inner wall surface side of the fixing portion is fitted into the upper portion of the auricle. An audio signal output device.

2. 2. The acoustic signal output device of claim 1, An acoustic signal output device, wherein the shielding wall is configured in a shape that covers the upper portion of the auricle while opening the lower portion of the auricle to the outside when the inner wall surface side of the fixing part is fitted into the upper portion of the auricle.

3. 3. The acoustic signal output device according to claim 2, An acoustic signal output device, wherein the shielding wall is configured in a shape that further opens a portion of the upper portion of the auricle to the outside when the inner wall surface side of the fixing portion is fitted into the upper portion of the auricle.

4. 4. The acoustic signal output device according to claim 1, Further comprising a driver unit that emits a first acoustic signal to one side and a second acoustic signal to the other side; a wall portion of the housing is provided with one or more first sound holes for guiding the first acoustic signal emitted from the driver unit to the outside, and one or more second sound holes for guiding the second acoustic signal emitted from the driver unit to the outside, the first sound hole is disposed on an inner side of the shielding wall, and the second sound hole is disposed on an outer side of the shielding wall, When the first acoustic signal is emitted from the first sound hole and the second acoustic signal is emitted from the second sound hole, an attenuation rate of the first acoustic signal at a second point farther from the acoustic signal output device than a predetermined first point where the first acoustic signal arrives is determined as a reference, a predetermined value smaller than an attenuation rate of an acoustic signal due to air propagation at the second point relative to the first point; Is designed to: an attenuation amount of the first acoustic signal at the second point relative to the first point, A predetermined value that is greater than the attenuation of the acoustic signal due to air propagation at the second point relative to the first point. It is designed to be more than An audio signal output device.

5. 5. The acoustic signal output device according to claim 4, an opening portion is provided in a portion of the shielding wall to partially expose a portion of the auricle to the outside when an upper portion of the auricle is fitted into the inner wall surface side of the fixing portion, An acoustic signal output device, wherein the opening area per unit area of ​​the second sound hole arranged on the side where the open portion is provided is larger than the opening area per unit area of ​​the second sound hole arranged on the side where the open portion is not provided.

6. 6. The acoustic signal output device according to claim 5, An acoustic signal output device, wherein the opening portion is provided in a position that opens the lower portion of the auricle to the outside when the inner wall surface side of the fixing portion is fitted into the upper portion of the auricle, and / or is provided in a position that opens a portion of the upper portion of the auricle to the outside.

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