Acoustic signal output device

Abstract

To provide a sound signal output device that does not hermetically seal an external acoustic meatus and can suppress sound leakage to the surroundings.SOLUTION: There is provided a sound signal output device 10 that is provided with a single or a plurality of sound holes 121a for emitting sound signals to the outside, and has a structure portion in which at least a part of an outer surface region 130 surrounding open ends of the sound holes 121a is formed in a convex shape. This outer surface region 130 includes a region 131 and a region 132 protruding beyond the region 131, and is configured in a shape that guides the sound signal emitted from the sound hole 121a toward the region 131 side.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an acoustic signal output device, and more particularly to an acoustic signal output device that does not seal the ear canal. [Background technology]

[0002] In recent years, the increased strain on the ears caused by wearing earphones and headphones has become a problem. Open-ear earphones and headphones, which do not block the ear canal, are known as devices that reduce strain on the ears. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] “WHAT ARE OPEN-EAR HEADPHONES?” [online], Bose Corporation, [Retrieved May 16, 2022], 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, open-ear earphones and headphones have the problem of significant sound leakage into the surroundings. This problem is not limited to open-ear earphones and headphones, but is a common problem with any acoustic signal output device that does not seal the ear canal.

[0005] The present invention has been made in view of the above points, and has an object to provide an acoustic signal output device that does not seal the ear canal and is capable of suppressing sound leakage to the surroundings. [Means for solving the problem]

[0006] An acoustic signal output device is provided that has one or more first sound holes for emitting a first acoustic signal to the outside, and has a structural part in which at least a part of an outer surface area surrounding the open end of the first sound hole is convex. This outer surface area includes a first area and a second area that protrudes beyond the first area, and is configured in a shape that guides the first acoustic signal emitted from the first sound hole toward the first area. [Effects of the Invention]

[0007] This makes it possible to suppress sound leakage to the surroundings without sealing the ear canal. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view illustrating the configuration of an acoustic signal output device according to an embodiment. [Figure 2] 2A and 2B are transparent plan and front views illustrating the configuration of an acoustic signal output device according to an embodiment. [Figure 3] Figure 3A is an end view 2BA-2BA of Figure 2B, and Figure 3B is an end view 2A-2A of Figure 2A. [Figure 4] 4A and 4B are conceptual diagrams illustrating the arrangement of sound holes. [Figure 5] FIG. 5 is a diagram illustrating a usage state of the acoustic signal output device according to the embodiment. [Figure 6] Fig. 6A is a diagram illustrating a usage state of the acoustic signal output device of the embodiment, and Fig. 6B is a diagram illustrating observation conditions for an acoustic signal emitted from the acoustic signal output device of the embodiment. [Figure 7] FIG. 7 is a diagram illustrating the state in which the acoustic signal output device of the embodiment is placed on a plane. [Figure 8] Fig. 8A is a front view illustrating the arrangement of the sound holes, and Fig. 8B and Fig. 8C are front views illustrating the arrangement of the sound holes. [Figure 9] 9A and 9B are conceptual diagrams illustrating the arrangement of sound holes. [Figure 10] 10A and 10B are conceptual diagrams illustrating the arrangement of sound holes. [Figure 11] Figure 11A is an end view 2BA-2BA of Figure 2B, and Figure 11B is an end view 2A-2A of Figure 2A. [Figure 12] Fig. 12A is a 2BA-2BA end view of Fig. 2B, and Fig. 12B is a conceptual diagram illustrating a drive system for an acoustic signal output device according to an embodiment. [Figure 13] FIG. 13 is a graph illustrating an example of equal-loudness contours (ISO 226:2003 Acoustics - Normal equal-loudness-level contours). [Figure 14] Fig. 14A is a graph illustrating the relationship between the volume of the internal space of the housing and the resonant frequency, and Fig. 14B is a graph illustrating the sound pressure level when an LPF (Low-pass filter) is used (with LPF) and when an LPF is not used (without LPF). [Figure 15] FIG. 15 is a diagram illustrating a configuration for attaching the acoustic signal output device of the embodiment to the auricle. [Figure 16] Fig. 16 is a diagram illustrating a configuration in which an acoustic signal output device of an embodiment is provided on the temples of glasses. Fig. 16A is a front view of the acoustic signal output device of an embodiment. Fig. 16B is an enlarged transparent view of Fig. 16A. Fig. 16C is an enlarged rear view of the acoustic signal output device of an embodiment. [Figure 17] 17 is a front view illustrating a modification of the acoustic signal output device of the embodiment. [Figure 18] 18A and 18B are perspective and plan views illustrating a modified example of the acoustic signal output device of the embodiment. [Figure 19] FIG. 19 is a plan view illustrating a modification of the acoustic signal output device of the embodiment. [Figure 20]FIG. 20A is a plan view illustrating a modified example of the acoustic signal output device of the embodiment. FIG. 20B is a right side view illustrating a modified example of the acoustic signal output device of the embodiment. FIG. 20C is a front view illustrating a modified example of the acoustic signal output device of the embodiment. FIG. 20D is a rear view illustrating a modified example of the acoustic signal output device of the embodiment. FIG. 20E is a front view illustrating a state in which the modified example of the acoustic signal output device of the embodiment is in use. [Figure 21] Fig. 21A is a perspective view illustrating a modified example of the acoustic signal output device of the embodiment, Fig. 21B is a perspective view illustrating a modified example of the acoustic signal output device of the embodiment, and Fig. 21C is a perspective view illustrating a state in which the modified example of the acoustic signal output device of the embodiment is used. [Figure 22] 22A and 22B are front and rear views illustrating a modified example of the acoustic signal output device of the embodiment. [Figure 23] 23A, 23B, and 23C are front views illustrating a modified example of the acoustic signal output device of the embodiment, a rear view illustrating the modified example of the acoustic signal output device of the embodiment, and a front view illustrating the modified example of the acoustic signal output device of the embodiment in use. [Figure 24] Fig. 24A is a plan view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 24B is a right side view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 24C is a front view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 24D is a rear view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 24E is a front view illustrating a state in which the modified example of the acoustic signal output device of the embodiment is in use. [Figure 25] Fig. 25A is a plan view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 25B is a front view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 25C is a rear view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 25D is a front view illustrating a state in which the modified example of the acoustic signal output device of the embodiment is used. [Figure 26]Fig. 26A is a plan view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 26B is a front view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 26C is a rear view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 26D is a front view illustrating a state in which the modified example of the acoustic signal output device of the embodiment is used. [Figure 27] 27A, 27B, and 27C are left and right side views illustrating a modified example of the acoustic signal output device of the embodiment, respectively, and are front and side views illustrating a state in which the modified example of the acoustic signal output device of the embodiment is used. [Figure 28] Fig. 28A is a plan view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 28B is a right side view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 28C is a front view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 28D is a rear view illustrating a modified example of the acoustic signal output device of the embodiment. Fig. 28E is a front view illustrating a state in which the modified example of the acoustic signal output device of the embodiment is in use. [Figure 29] 29A and 29B are conceptual diagrams and perspective views illustrating a modified example of the acoustic signal output device of the embodiment. [Figure 30] 30A, 30B, and 30C are front, left, and right side views illustrating a modified example of the acoustic signal output device of the embodiment. [Figure 31] 31A, 31B, and 31C are front, left, and right side views illustrating a modified example of the acoustic signal output device of the embodiment. [Figure 32] 32A and 32B are front and rear views illustrating a modified example of the acoustic signal output device of the embodiment. [Figure 33] FIG. 33 is a conceptual diagram illustrating a modified example of the acoustic signal output device of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [First embodiment] Acoustic signal output device 10 of this embodiment is a device for listening to sound (for example, open-ear earphones, headphones, etc.) that is worn without sealing the user's ear canal. As illustrated in Figures 1, 2A, 2B, 3A, and 3B, acoustic signal output device 10 of this embodiment has a driver unit 11 that converts an output signal (an electrical signal representing an acoustic signal) output from a playback device into an acoustic signal and outputs it, a housing 12 (structural part) that houses driver unit 11 inside, and a support part 13 (structural part) that is placed on the user's auricle when worn.

[0010] <Driver unit 11> The driver unit (speaker driver unit) 11 is a device (device with speaker functionality) that emits (emits sound) an acoustic signal AC1 (first acoustic signal) based on an input output signal to one side (the D1 direction), and emits an acoustic signal AC2 (second acoustic signal) that is an inverse phase signal (phase-inverted signal) of the acoustic signal AC1 or a signal approximating the inverse phase signal to the other side (the D2 direction). That is, the acoustic signal emitted from the driver unit 11 to one side (the D1 direction) will be called the acoustic signal AC1 (first acoustic signal), and the acoustic signal emitted from the driver unit 11 to the other side (the D2 direction) will be called the acoustic signal AC2 (second acoustic signal). The acoustic signal AC1 is used by the user to hear the sound, and the acoustic signal AC2 is used to suppress sound leakage to the surroundings. For example, driver unit 11 includes diaphragm 113 that emits acoustic signal AC1 in the D1 direction from one surface 113a by vibration, and emits acoustic signal AC2 in the D2 direction from the other surface 113b by this vibration (FIG. 2B). In this example, driver unit 11 emits acoustic signal AC1 from one surface 111 in the D1 direction by vibrating diaphragm 113 based on an input output signal, and emits acoustic signal AC2, which is an inverse phase signal of acoustic signal AC1 or a signal approximating the inverse phase signal, from the other surface 112 in the D2 direction. In other words, acoustic signal AC2 is emitted secondarily in conjunction with the emission of 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 one side (D1 direction) and the other side (D2 direction) depends on the type and shape of driver unit 11. Furthermore, depending on the type and shape of driver unit 11, acoustic signal AC2 may be strictly an inverse phase signal of acoustic signal AC1, or acoustic signal AC2 may be an approximation of the inverse phase signal of acoustic signal AC1. For example, the approximation of the inverse phase signal of acoustic signal AC1 may be (1) a signal obtained by shifting the phase of the inverse phase signal of acoustic signal AC1, (2) a signal obtained by changing (amplifying or attenuating) the amplitude of the inverse phase signal of acoustic signal AC1, or (3) a signal obtained by shifting the phase of the inverse phase signal of acoustic signal AC1 and then changing the amplitude.The phase difference between the antiphase signal of acoustic signal AC1 and its approximation signal is desirably δ1 (rad) or less. Examples of δ1 include π / 36, π / 12, π / 6, and π / 3. Furthermore, the ratio of the amplitude of the antiphase signal of acoustic signal AC1 to the amplitude of the approximation signal is desirably δ2 or less. Examples of δ2 include 0.1, 0.5, 1.0, and 2.0. For example, it is sufficient if the amplitude of the sum signal obtained by adding acoustic signal AC1 and acoustic signal AC2 emitted from driver unit 11 is smaller than the amplitude of acoustic signal AC1. For example, the sine waves of each frequency included in acoustic signal AC1 emitted from driver unit 11 are denoted as Ae^jωt, and the sine waves of each frequency included in acoustic signal AC2 emitted from driver unit 11 are denoted as δ2Ae^j(-ωt+δ1). where t represents time, ω represents angular frequency, A (A>0) represents amplitude, j represents the imaginary unit, and e represents Napier's constant. δ1 represents the phase difference (rad) between the opposite phase signal of acoustic signal AC1 and acoustic signal AC2, and δ2 (δ2>0) represents the amplitude ratio between the opposite phase signal of acoustic signal AC1 and acoustic signal AC2. The sum signal obtained by adding both signals is as follows: (Ae^jωt)+{δ2Ae^j(-ωt+δ1)}=(1-δ2e^jδ1)Ae^jωt Since the absolute value of the amplitude of this sum signal is |(1-δ2e^jδ1)A|, in order to make the amplitude of the sum signal smaller than the amplitude of the acoustic signal AC1, it is necessary to make |(1-δ2e^jδ1)|<1. In other words, the following condition must be satisfied.

number

[0011] <Case 12> Housing 12 is a hollow member with an outer wall, and houses driver unit 11 inside. For example, driver unit 11 is fixed to the end of housing 12 on the D1 direction side. However, this does not limit the present invention. There are also no limitations on the shape of housing 12, and for example, the shape of housing 12 may be rotationally symmetric (line symmetric) or approximately rotationally symmetric about axis A1 extending along the D1 direction. Note that axis A1 is an axis that extends in the D1 direction through a central region of housing 12. For example, housing 12 has wall 121 arranged on one side (D1 direction side) of driver unit 11, wall 122 arranged on the other side (D2 direction side) of driver unit 11, and wall 123 (side surface) that surrounds the space between wall 121 and wall 122, with axis A1 passing through wall 121 and wall 122 as the center (FIGS. 2B and 3B). In this embodiment, for the sake of simplicity, an example is shown in which the housing 12 has a substantially cylindrical shape with both end faces. However, this is merely an example and does not limit the present invention. For example, the housing 12 may have a substantially dome-like shape with wall portions at the ends, a hollow substantially cubic shape, or any other three-dimensional shape. Furthermore, there are no limitations 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 an elastic body such as rubber.

[0012] <Sound holes 121a, 123a> The wall of housing 12 is provided with sound hole 121a (first sound hole) that emits (derives) to the outside acoustic signal AC1 (first acoustic signal) emitted from driver unit 11, and sound hole 123a (second sound hole) that emits (derives) to the outside acoustic signal AC2 (second acoustic signal) emitted from driver unit 11. Sound hole 121a and sound hole 123a are, for example, through-holes that penetrate the wall of housing 12, but this does not limit the present invention. Sound hole 121a and sound hole 123a do not have to be through-holes as long as they can emit acoustic signal AC1 and acoustic signal AC2 to the outside, respectively.

[0013] In this embodiment, sound hole 121a (first sound hole) is provided in region AR1 (first region) of wall portion 121 located on one side of driver unit 11 (the D1 direction side, which is the side from which acoustic signal AC1 is emitted) (FIGS. 2B and 3B). Sound hole 121a in this embodiment is located at an eccentric position offset in the B1 direction (first direction) from axis A1 (the central axis of the structural portion), and opens toward the D1 direction. The B1 direction is a specific radiation direction centered on axis A1. In this embodiment, for simplicity of explanation, an example is shown in which the edge shape of the open end of sound hole 121a is elliptical (the open end is elliptical). However, this does not limit the present invention. For example, the shape of the edge of sound hole 121a may be circular, rectangular, triangular, or another shape. Furthermore, the end of sound hole 121a may be mesh-like. In other words, the end of sound hole 121a may be composed of multiple holes. In addition, in this embodiment, for the sake of simplicity, 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.

[0014] Sound hole 123a (second sound hole) in this embodiment is provided in area AR3 of wall portion 123 that contacts area AR between area AR1 of wall portion 121 of housing 12 and area AR2 of wall portion 122 that is arranged on the D2 direction side (the other side that is the side from which acoustic signal AC2 is emitted) of driver unit 11. In other words, if the center of housing 12 is used as a reference and the direction between D1 direction and the direction opposite to D1 direction is defined as D12 direction ( FIG. 3B ), sound hole 123a (second sound hole) is provided on the D12 direction side of housing 12. For example, when housing 12 has wall portion 121 arranged on one side (D1 direction side) of driver unit 11, wall portion 122 arranged on the other side (D2 direction side) of driver unit 11, and wall portion 123 (side surface) that surrounds the space sandwiched between wall portions 121 and 122 around axis A1 along the emission direction (D1 direction) of acoustic signal AC1 that passes through wall portions 121 and 122 (Figures 2B and 3B), sound hole 123a (second sound hole) is provided in wall portion 123 (side surface).

[0015] Furthermore, sound holes 123a (second sound holes) of this embodiment are arranged biased toward the B2 direction (second direction) side. The B2 direction (second direction) is a direction that includes a component in the opposite direction of the B1 direction (first direction). For example, sound holes 123a (second sound holes) are not provided on the B1 direction (first direction) side of axis A1. As illustrated in FIGS. 4A and 4B, when sound holes 123a (second sound holes) are arranged in this manner, the total area of ​​the opening ends of sound holes 123a (second sound holes) that face space SP1 (first space) is smaller than the total area of ​​the opening ends of sound holes 123a (second sound holes) that face space SP2 (second space). As a result, the sound pressure level of acoustic signal AC2 (second acoustic signal) emitted from sound hole 123a (second sound hole) into space SP1 (first space) is lower than the sound pressure level of acoustic signal AC2 (second acoustic signal) emitted from sound hole 123a (second sound hole) into space SP2 (second space). Note that space SP1 (first space) is a space located on the B1 direction (first direction) side of sound hole 121a (first sound hole), and space SP2 (second space) is a space located on the B2 direction (second direction) side of sound hole 121a (first sound hole). In other words, it is preferable to design the device so that, for example, the farther away from the position of sound hole 121a on housing 12, the more sound holes 123a are arranged, and the closer to the position of sound hole 121a on housing 12, the fewer sound holes 123a are arranged.

[0016] It is preferable not to provide a sound hole on the wall 122 side of the housing 12. If a sound hole is provided on the wall 122 side of the housing 12, the sound pressure level of the acoustic signal AC2 emitted from the housing 12 will exceed the level necessary to cancel out the sound leakage component of the acoustic signal AC1, and this excess will be perceived as sound leakage.

[0017] <Support Section 13> 1, 2B, and 3B, the support portion 13 is a convex portion provided on the outer surface of the wall portion 121 on the D1 direction side of the housing 12. The support portion 13 is provided with an open end 131b of the sound hole 121a, and the acoustic signal AC1 emitted from the sound hole 121a is emitted to the outside from the open end 131b. For example, the open end 131b is a through hole, and emits the acoustic signal AC1 emitted from the sound hole 121a to the outside.

[0018] At least a portion of the outer surface region 130 of the support unit 13 has a convex shape. The outer surface region 130 is an outer surface region surrounding the open end 131b of the sound hole 121a (first sound hole), and is, for example, an annular region located on the outer surface side of the support unit 13 in the direction D1. The outer surface region 130 includes a region 131 (first region) and a region 132 (second region) that protrudes from the region 131 (first region), and is configured in a shape that guides the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) toward the region 131 (first region). In this example, the region 131 (first region) is located on the B1 direction (first direction) side of the region 132 (second region), and the outer surface region 130 guides the acoustic signal AC1 emitted from the sound hole 121a toward the B1 direction. For example, opening end 131b of sound hole 121a (first sound hole) faces space SP surrounded by area 132 (second area), and the area 131 (first area) side of space SP is open outward (outward in the direction B1) from the outer periphery of space SP. That is, for example, area 132 is a convex-shaped area in which surface 132a protrudes outward (in the direction D1) beyond surface 131a of area 131, and surrounds the area around opening end 131b except for the area 131 (first area) side (the B1 direction side). In other words, for example, area 131 is recessed more than area 132, and area 132 is curved so as to partially surround the periphery of opening end 131b of area 131. That is, in this example, region 131 is located on the B1 direction (first direction) side of open end 131b of sound hole 121a, and region 132 is a region that bulges outward from open end 131b in a 360-degree radial direction, except for a portion of the B1 direction side. For example, region 132 has a mountain shape with one or more peaks. Furthermore, surface 132a of region 132 is connected to surface 131a of region 131 via inclined portion 132c of region 132. That is, in this example, inclined portion 132c has a tapered shape that widens from surface 131a to surface 132a. In this case, acoustic signal AC1 emitted from sound hole 121a can be efficiently guided to the ear canal of a user positioned on the region 131 side (B1 direction side) when wearing acoustic signal output device 10. However, the open end 131b side of region 132 does not have to be tapered.Furthermore, the open end of sound hole 123a (second sound hole) faces the space outside the space SP surrounded by region 132 (second region). More specifically, the open end of sound hole 123a (second sound hole) in this embodiment faces the space outside the space surrounded by outer surface region 130. In addition, as described above, sound hole 123a (second sound hole) is arranged biased toward direction B2 (second direction). As a result, acoustic signal AC2 emitted from sound hole 123a is less likely to reach the user's ear canal than acoustic signal AC1 emitted from sound hole 121a.

[0019] The illustrated shape of the support section 13 is merely an example and does not limit the present invention. For example, if the surface 132a of the region 132 protrudes in the D1 direction more than the surface 131a of the region 131, the surface 131a of the region 131 and the surface 132a of the region 132 may be convex, concave, uneven, or flat. However, a curved, convex surface 132a of the region 132 provides a better fit when worn. Furthermore, there are no limitations on the material from which the support section 13 is made. The support section 13 may be made of a rigid body such as a synthetic resin, or an elastic body such as rubber or urethane. However, an elastic body from the region 132 provides a better fit when worn.

[0020] <Wearing state> 5 illustrates an example of how the acoustic signal output device 10 is worn. The acoustic signal output device 10 of this embodiment is worn on the pinna 1010 (body) of the user 1000 so that the support unit 13 faces the pinna 1010. When the housing 12 and the support unit 13 (structural unit) are attached to the pinna 1010 of the user 1000 in this manner, the region 132 (second region) of the support unit 13 is supported by contacting any part of the pinna 1010 (body), and the opening end 131b of the sound hole 121a (first sound hole) and the region 131 (first region) of the support unit 13 are not in contact with at least a part of the pinna 1010 (body), with the region 131 (first region) being positioned on the ear canal 1011 side. For example, when the acoustic signal output device 10 is worn, the region 132 is positioned above the pinna 1010, and the surface 132a of the region 132 is in contact with and supported by an upper portion of the pinna 1010 (e.g., the triangular fossa or the scaphoid fossa). This prevents the sound hole 121a from coming into contact with any part of the pinna 1010 of the user 1000 and being blocked. Furthermore, the region 131 contacts the pinna 1010 and acts as a support, providing a high sense of stability when worn. In particular, when the region 131 has a convex shape, the region 131 fits into the concave shape of the pinna 1010 and acts as a support, thereby increasing the sense of stability when worn. This effect is more pronounced when the region 131 is an elastic body than when it is a rigid body. When the acoustic signal output device 10 is worn, for example, the region 131 is positioned below the region 132 (toward the ear canal 1011) As described above, the outer surface region 130 of the support unit 13 is configured in a shape that guides the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) toward the region 131 (first region) side (toward the direction of B1). Therefore, the acoustic signal AC1 emitted from the sound hole 121a is guided toward the ear canal 1011 side (below the pinna 1010) and emitted. Because the region 132 supported by the pinna 1010 protrudes further than the region 131, the opening edge 131b and at least a part of the region 131 do not contact the pinna 1010. Preferably, the opening edge 131b and the region 131 do not contact the pinna 1010. Furthermore, the support unit 13 does not block the ear canal 1011. This allows the acoustic signal AC1 emitted from the sound hole 121a to efficiently reach the ear canal 1011.Furthermore, as described above, when the inclined portion 132c of the support unit 13 has a tapered shape that widens from the surface 131a to the surface 132a, the acoustic signal AC1 emitted from the sound hole 121a reaches the ear canal 1011 more efficiently. On the other hand, the B2 side of the open end 131b of the sound hole 121a is surrounded by the region 132, so that the acoustic signal AC1 emitted from the sound hole 121a can be prevented from leaking in the B2 direction (sound leakage). That is, when the housing 12 and the support unit 13 (structural unit) are attached to the auricle 1010 (body), the sound pressure level of the acoustic signal AC1 (first acoustic signal) emitted from the ear canal 1011 toward the ear canal 1011 becomes higher than the sound pressure level of the acoustic signal AC1 (first acoustic signal) emitted from the area other than the ear canal 1011 toward a side other than the ear canal 1011.

[0021] Furthermore, the open end of the sound hole 123a (second sound hole) in this embodiment faces the space outside the space SP surrounded by the region 132 (second region). The sound hole 123a (second sound hole) is also positioned biased toward the B2 direction (second direction). This makes it more difficult for the acoustic signal AC2 emitted from the sound hole 123a to reach the ear canal 1011 of the user 1000 compared to the acoustic signal AC1 emitted from the sound hole 121a. Furthermore, this acoustic signal AC2 cancels out the acoustic signal AC1 that has leaked to the outside, thereby suppressing sound leakage. This will be explained using FIGS. 6A and 6B. In the example of FIG. 6A, one acoustic signal output device 10 is attached to each of the pinna 1010 of the right ear and the pinna 1020 of the left ear of the user 1000. Any suitable attachment mechanism is used to attach the acoustic signal output device 10 to the ear. As described above, the D1 direction side of each acoustic signal output device 10 is directed toward 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 toward the D1 direction side and an acoustic signal AC2 toward the other side. The acoustic signal AC1 is emitted from the sound hole 121a, enters the ear canals 1011 of the right and left ears, and is heard by the user 1000. Meanwhile, the acoustic signal AC2, which is an inverse phase signal of the acoustic signal AC1 or a signal approximating the inverse phase signal, is emitted from the sound hole 123a. A portion of this acoustic signal AC2 cancels out a portion (sound leakage component) of the acoustic signal AC1 emitted from the sound hole 121a. That is, an acoustic signal AC1 (first acoustic signal) is emitted from the sound hole 121a (first sound hole) and an acoustic signal AC2 (second acoustic signal) is emitted from the sound hole 123a (second sound hole), so that the attenuation rate η of the acoustic signal AC1 (first acoustic signal) at the position P2 (second position) relative to the position P1 (first position) is 11 Set a 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 thor more. Here, 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, position P2 (second point) is a predetermined point that is farther from the acoustic signal output device 10 than position P1 (first point). Positions P1 and P2 may be any points, but for example, positions P1 and P2 are positions in a direction other than the B1 direction of the acoustic signal output device 10, such as positions B2 and D2 of the acoustic signal output device 10. A predetermined value η th is the attenuation rate η of any or specific acoustic signal (sound) due to air propagation at position P2 (second position) relative to position P1 (first position). 21 In addition, the predetermined value ω th is 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 this 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. The attenuation rate η 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, if 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 ar is attenuated due to air propagation, not due to the acoustic signal AC2. 21is the acoustic signal AC at position P1 ar The size of AMP1 (AC ar ) at position P2, which is attenuated due to air propagation (attenuation without being attributable to acoustic signal AC2) ar Size of AMP2 (AC ar ) ratio (AMP2(AC ar ) / AMP1(AC ar )) Also, the attenuation η 22 is the magnitude AMP1(AC ar ) and size AMP2(AC ar ) and the difference (|AMP1(AC ar )-AMP2(AC ar )|). Examples of the magnitude of an acoustic signal include the sound pressure of the acoustic signal or the energy of the acoustic signal. Furthermore, the "sound leakage component" refers to, for example, a component of the acoustic signal AC1 emitted from the sound hole 121a that is likely to reach an area other than the user 1000 wearing the acoustic signal output device 10 (for example, a person other than the user 1000 wearing the acoustic signal output device 10). For example, the "sound leakage component" refers to a component of the acoustic signal AC1 that propagates in a direction other than direction D1. For example, the direct wave of the acoustic signal AC1 is mainly emitted from the sound hole 121a, and the direct wave of the second acoustic signal is mainly emitted from the second sound hole. A portion of the direct wave of the acoustic signal AC1 emitted from the sound hole 121a (the sound leakage component) is canceled out by interference with at least a portion of the direct wave of the acoustic signal AC2 emitted from the sound hole 123a. However, this does not limit the present invention, and this cancellation can occur with waves 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 canceled out by at least one of the direct wave and the reflected wave of the acoustic signal AC2 emitted from the sound hole 123a, thereby suppressing sound leakage.

[0022] Furthermore, because sound hole 123a (second sound hole) is disposed biased toward the B2 direction (second direction) side, acoustic signal AC2 emitted from sound hole 123a is less likely to reach the ear canal 1011 side. Therefore, on the ear canal 1011 side, acoustic signal AC1 is less likely to be canceled out by acoustic signal AC2. In other words, because sound hole 123a is away from the ear canal 1011, acoustic signal AC2 emitted from sound hole 123a is less likely to cancel out acoustic signal AC1 emitted from sound hole 121a toward the ear canal 1011 side. In other words, acoustic signal AC2 can suppress sound leakage of acoustic signal AC1 leaking to places other than the ear canal 1011 side without significantly suppressing acoustic signal AC1 emitted toward the ear canal 1011 side. For example, when the acoustic signal output device 10 is attached to the auricle 1010, it is desirable that the distance from the ear canal 1011 to the sound hole 121a be 2 cm or more and 3 cm or less, and the distance from the sound hole 121a to the sound hole 123a be 2 cm or more. However, this does not limit the present invention.

[0023] <Abandoned state> As illustrated in FIG. 7 , the acoustic signal output device 10 is placed on a flat surface 1100 such as a desk. In FIG. 7 , the support unit 13 is disposed on the flat surface 1100. Even in this case, the region 132 protrudes from the region 131, so the opening end 131b of the sound hole 121a and at least a portion of the region 131 do not contact the flat surface 1100. Therefore, the acoustic signal AC1 emitted from the opening end 131b of the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a cancel each other out as described above, thereby suppressing sound leakage. In other words, in this embodiment, the position and size of the region 132 and the shape and angle of the surface 132a of the region 132 are set so that the opening end 131b of the sound hole 121a and at least a portion of the region 131 do not contact the flat surface 1100.

[0024] Such an effect can also be obtained when the housing 12 side is placed on the flat surface 1100. That is, no matter what orientation the acoustic signal output device 10 of this embodiment is placed on the flat surface 1100, the acoustic signal AC1 emitted from the opening end 131b of the sound hole 121a and the acoustic signal AC2 emitted from the sound hole 123a cancel each other out as described above, thereby suppressing sound leakage.

[0025] [Modification of the first embodiment] The shape, size, and arrangement of sound hole 121a and sound hole 123a are not limited to those exemplified in the first embodiment. For example, the first embodiment showed an example in which one sound hole 121a is provided in area AR1 of housing 12, and open end 131b of one sound hole 121a is provided in support part 13. However, as exemplified in Fig. 8A, multiple sound holes 121a may be provided in area AR1 of housing 12, and multiple open ends 131b of sound holes 121a may be provided in support part 13. In this case, these multiple sound holes 121a and open ends 131b may be offset to eccentric positions shifted in the B1 direction from axis A1.

[0026] In the first embodiment, an example was shown in which sound holes 123a of the same shape and size were arranged on the same circumference of wall 123 of housing 12. However, as long as the open end of sound hole 123a faces the space outside space SP surrounded by region 132 and sound hole 123a is arranged biased toward the B2 direction, sound hole 123a may have any shape and size. That is, it is sufficient that the sound pressure level of acoustic signal AC2 emitted from sound hole 123a into space SP1 is lower than the sound pressure level of acoustic signal AC2 emitted from sound hole 123a into space SP2. As described above, space SP1 is a space located on the B1 direction side of sound hole 121a, and space SP2 is a space located on the B2 direction side of sound hole 121a.

[0027] For example, as illustrated in FIG. 8B, multiple sound holes 123a (second sound holes) of different sizes may be provided, or as illustrated in FIG. 8C, multiple sound holes 123a (second sound holes) of different shapes may be provided, and the multiple sound holes 123a do not have to be arranged on the same circumference.

[0028] 9A and 9B, sound holes 123a may also be provided on the B1 side of axis A1. Even in this case, it is sufficient that the opening area of ​​the sound holes 123a located on the B1 side of axis A1 is smaller than the opening area of ​​the sound holes 123a located biased toward the B2 side, or that the opening area per unit area (i.e., the density of the opening area) of the sound holes 123a located on the B1 side of axis A1 is smaller than the opening area per unit area of ​​the sound holes 123a located biased toward the B2 side. This makes the total area of ​​the opening ends of the sound holes 123a facing space SP1 smaller than the total area of ​​the opening ends of the sound holes 123a facing space SP2, and the sound pressure level of the acoustic signal AC2 emitted from the sound holes 123a into space SP1 is lower than the sound pressure level of the acoustic signal AC2 emitted from the sound holes 123a into space SP2. For example, the opening area of ​​the open end of sound hole 123a that is a distance α1 from open end 131b of sound hole 121a may be designed to be smaller than the opening area of ​​the open end of sound hole 123a that is a distance α2 from open end 131b of sound hole 121a, where α1 < α2. For example, the opening area of ​​the open end of sound hole 123a that is closer to open end 131b of sound hole 121a may be configured to be smaller.

[0029] 10A and 10B, even if sound hole 123a is provided on the B1 side of axis A1, it is sufficient that the sound pressure level of acoustic signal AC2 emitted therefrom is lower than the sound pressure level of acoustic signal AC2 emitted from sound hole 123a located biased toward the B2 side. For example, acoustic signal AC2 emitted from driver unit 11 may have directionality, such that the sound pressure level of acoustic signal AC2 emitted from sound hole 123a located on the B1 side of axis A1 is lower than the sound pressure level of acoustic signal AC2 emitted from sound hole 123a located biased toward the B2 side. Alternatively, multiple driver units 11 with different output powers may be housed inside housing 12, such that the sound pressure level of acoustic signal AC2 emitted from sound hole 123a located on the B1 side of axis A1 is lower than the sound pressure level of acoustic signal AC2 emitted from sound hole 123a located biased toward the B2 side. Alternatively, a material that attenuates acoustic signals may be placed at the opening of sound hole 123a provided on the B1 direction side of axis A1, or the opening of sound hole 123a provided on the B1 direction side of axis A1 may have a shape such as a mesh structure that attenuates acoustic signals. That is, it is sufficient if a plurality of sound holes 123a (second sound holes) are provided in housing 12, and the sound pressure level of acoustic signal AC2 (second acoustic signal) emitted from the opening end of sound hole 123a (second sound hole) that faces space SP1 (first space) is lower than the sound pressure level of acoustic signal AC2 (second acoustic signal) emitted from the opening end of sound hole 123a (second sound hole) that faces space SP2 (second space). The design may be such that the sound pressure level of acoustic signal AC2 emitted from the open end of sound hole 123a that is a distance α1 from open end 131b of sound hole 121a is smaller than the sound pressure level of acoustic signal AC2 emitted from the open end of sound hole 123a that is a distance α2 from open end 131b of sound hole 121a, where α1<α2. For example, the design may be such that the closer the sound hole 123a is to open end 131b of sound hole 121a, the smaller the sound pressure level of the emitted acoustic signal AC2.

[0030] Furthermore, in the first embodiment, an example was shown in which a plurality of sound holes 123a were provided in the housing 12, but a single sound hole 123a may be provided in the housing 12. In this case, it is desirable that the open end of sound hole 123a be as far away from sound hole 121a as possible. It is preferable that sound hole 123a be provided so that the distance between the open end of sound hole 123a and sound hole 121a is maximized.

[0031] [Second embodiment] Next, a second embodiment will be described. The second embodiment is a further modification of the first embodiment and its modifications. The following description will focus on differences from the matters described so far, and will briefly explain matters that have already been described.

[0032] The acoustic signal output device 10 illustrated in the first embodiment suppresses sound leakage by emitting an acoustic signal AC2 from the sound hole 123a, thereby canceling out the acoustic signal AC1 that was emitted from the sound hole 121a and leaked to the outside. Ideally, this is based on the acoustic signal AC2 being out of phase with the acoustic signal AC1. However, because the propagation paths of the acoustic signals AC1 and AC2 are different, a phase difference occurs between the acoustic signals AC1 and AC2, and the acoustic signal AC2 may not be out of phase with the acoustic signal AC1 at the position where sound leakage is desired to be suppressed. This effect becomes more pronounced as the frequencies of the acoustic signals AC1 and AC2 increase, making it difficult to suppress sound leakage as the frequencies increase. In some cases, the acoustic signal AC2 does not cancel out the acoustic signal AC1, and instead the acoustic signal AC2 is perceived as a sound leakage component. For example, the acoustic signal AC2 can suppress sound leakage of the acoustic signal AC1 only when the frequencies of the acoustic signals AC1 and AC2 are up to about 3 kHz. At frequencies above this, the acoustic signal AC2 also becomes a sound leakage component.

[0033] Furthermore, the human ear is sensitive to the 3 kHz to 6 kHz band, and perceives even softer sounds in this band as louder than in other bands. This human hearing characteristic is expressed as an equal loudness curve. This equal loudness curve plots the sound pressure levels at which sounds of various frequencies are perceived as having the same loudness. Figure 13 shows the equal loudness curves. The horizontal axis of Figure 13 represents frequency [Hz], and the vertical axis represents sound pressure level [dB]. As shown in Figure 13, the equal loudness curves have a minimum around 4 kHz, indicating that human hearing sensitivity is high at this frequency. Therefore, it is desirable to lower the sound pressure level of the acoustic signal AC2 in the 3 kHz to 6 kHz band, where human hearing sensitivity is high.

[0034] Furthermore, as mentioned above, acoustic signal AC2 emitted from driver unit 11 is emitted into region AR, which is the internal space of housing 12 (enclosure), and then emitted to the outside through sound hole 123a. The sound pressure level of acoustic signal AC2 reaches a maximum at the resonance frequency of region AR. Therefore, in order to suppress sound leakage at high frequencies, it is desirable to set this resonance frequency above the band where human hearing sensitivity is high (for example, 6 kHz or higher). FIG. 14A illustrates an example of the relationship between the volume of region AR and acoustic signal AC2 emitted to the outside through sound hole 123a. As illustrated in FIG. 14A, it can be seen that the smaller the volume of region AR, the higher the resonance frequency fr. Therefore, it is believed that the impact of sound leakage can be reduced by reducing the volume (capacity) of region AR and setting the resonance frequency of region AR above the band where human hearing sensitivity is high (for example, 6 kHz or higher).

[0035] However, if the resonant frequency of the area AR is set to be higher than the band where human hearing sensitivity is high, the sound pressure level will also increase in the band around this resonant frequency, and the sound pressure level in the band where human hearing sensitivity is high will also increase. Therefore, in this embodiment, a further measure is taken to reduce the high-frequency side of the acoustic signal AC2 emitted to the outside from the sound hole 123a. This makes it possible to reduce sound leakage in the band where human hearing sensitivity is high (for example, the band of 3 kHz to 6 kHz).

[0036] Acoustic signal output device 20 of this embodiment has a driver unit 11, a housing 12 (structural part) that houses driver unit 11 inside, and a support part 13 (structural part) that is placed on the user's auricle when worn. Housing 12 (structural part) is provided with one or more sound holes 121a (first sound holes) that emit an acoustic signal AC1 (first acoustic signal) to the outside, a hollow part that emits an acoustic signal AC2 (second acoustic signal) into an area AR (internal space), and one or more sound holes 123a (second sound holes) that emit the acoustic signal AC2 (second acoustic signal) emitted into the area AR (internal space) of the hollow part to the outside. Here, the hollow portion is designed so that its resonant frequency is equal to or higher than a predetermined frequency (for example, equal to or higher than the band where human hearing sensitivity is high, for example, 6 kHz or higher), and the acoustic signal AC2 (second acoustic signal) is designed so that frequency band components including the predetermined frequency (for example, band components where human hearing sensitivity is high, for example, band components between 3 kHz and 6 kHz) are suppressed and emitted to the outside from the sound hole 123a (second sound hole). This makes it possible to reduce sound leakage in the band where human hearing sensitivity is high (for example, the band between 3 kHz and 6 kHz). An example of such a design is shown below.

[0037] <Design example 1> As illustrated in FIG. 11A , the housing 12 (structural section) of the acoustic signal output device 20 may have an internal hollow section 241 disposed in an area AR (internal space) of the hollow section 220. The internal space ISP of the internal hollow section 241 is spatially separated from the area AR (internal space) of the hollow section 220 located outside the internal hollow section 241. That is, the internal hollow section 241 is a hollow member having a wall section 242 on the outside, and the internal space ISP is spatially separated from the area AR by the wall section 242. As long as the internal hollow section 241 has such an internal space ISP, the shape of the internal hollow section 241 may be any shape. There is no limitation on the material constituting the wall section 242. The wall section 242 may be made of a rigid body such as synthetic resin or metal, or may be made of an elastic body such as rubber. Furthermore, the internal space ISP of the internal hollow section 241 may be completely sealed or may not be completely sealed as long as it is spatially separated from the area AR. The internal space ISP may be filled with air or other gases, and may further include a material such as an elastic body. However, it is desirable that the material disposed in the internal space ISP be softer than the wall portion 242. In this example, the bottom surface 242a of the wall portion 242 of the internal hollow portion 241 is fixed to the region AR2 inside the hollow portion 220. However, this is just one example, and any region of the wall portion 242 of the internal hollow portion 241 may be fixed to any region inside the hollow portion 220. By disposing the internal hollow portion 241 in the region AR of the hollow portion 220 and forming a double structure by the hollow portion 220 and the internal hollow portion 241, the volume of the region AR can be reduced and the resonant frequency of the hollow portion 220 can be increased. Therefore, by appropriately designing the volume of the internal hollow portion 241, the resonant frequency of the hollow portion 220 can be set above the frequency band where human hearing sensitivity is high (e.g., 6 kHz or higher). In particular, there is a high degree of freedom in the design of internal hollow portion 241, and the shape and size of internal hollow portion 241 can be set so that the volume of area AR is sufficiently small. For example, it is possible to design internal hollow portion 241 so that it does not come into contact with driver unit 11 and is as close to driver unit 11 as possible, which makes it possible to sufficiently increase the resonant frequency of hollow portion 220.Furthermore, the air in the internal space ISP of the internal hollow portion 241 acts as a damper to reduce vibrations in the hollow portion 220, thereby suppressing the high-frequency band components of the acoustic signal AC2 (second acoustic signal) emitted to the outside from the sound hole 123a (second sound hole).

[0038] <Design example 2> 11B , cushioning material 25 may be disposed between bottom surface 242a (outside) of internal hollow portion 241 and region AR2 (inside) of hollow portion 220, and bottom surface 242a (outside) of internal hollow portion 241 may be fixed to region AR2 (inside) of hollow portion 220 via cushioning material 25. Note that in this example, cushioning material 25 is disposed on bottom surface 242a of internal hollow portion 241, but cushioning material 25 may be disposed between other wall portions 242 of internal hollow portion 241 and the inside of hollow portion 220, and other wall portions 242 of internal hollow portion 241 may be fixed to the inside of hollow portion 220 via cushioning material 25. Cushioning material 25 is softer than wall portions 122 of housing 12 and wall portions 242 of internal hollow portion 241, thereby further reducing vibrations in hollow portion 220. This makes it possible to suppress the high-frequency band components of the acoustic signal AC2 emitted to the outside from the sound hole 123a. Examples of materials for the buffer material 25 include paper, urethane, and rubber, and for example, double-sided tape made of paper may be used as the buffer material 25. However, this does not limit the present invention. Furthermore, if such a buffer material 25 is provided, a filled solid member may be used instead of the internal hollow portion 241.

[0039] <Design example 3> As illustrated in FIG. 12A, at least a portion of the electronic components 26 for driving the driver unit 11 may be housed in the internal space ISP of the internal hollow portion 241. This allows the internal space of the internal space ISP, which functions as a damper, to be used as an arrangement space for the electronic components 26, thereby enabling the size of the housing 12 to be reduced. Examples of the electronic components 26 include wiring cables, electronic components, and electronic circuit boards. Considering their function as a damper, it is desirable that the electronic components 26 be made of a material that is softer than the wall portion 242, such as wiring cables. Furthermore, as described in Design Example 2, a buffer material 25 may be disposed between the bottom surface portion 242a (outside) of the internal hollow portion 241 and the region AR2 (inside) of the hollow portion 220, and the bottom surface portion 242a (outside) of the internal hollow portion 241 may be fixed to the region AR2 (inside) of the hollow portion 220 via the buffer material 25.

[0040] <Design Example 4> In addition to the configurations described in design examples 1 to 3, driver unit 11 may further emit, into area AR (internal space) of hollow portion 220, an acoustic signal AC2 (second acoustic signal) in which frequency band components (for example, band components for which human hearing sensitivity is high, for example, 3 kHz-6 kHz band components) including the aforementioned predetermined frequency (for example, a band for which human hearing sensitivity is high, for example, 6 kHz) are suppressed. For example, as illustrated in FIG. 12B, an LPF (low-pass filter) section 200 may be provided between driver unit 11 and playback device 100 that outputs an output signal for driving driver unit 11. This low-pass filter suppresses (attenuates or flattens) frequency band components including the aforementioned predetermined frequency (for example, a band for which human hearing sensitivity is high). For example, the cutoff frequency of this low-pass filter is set to 3 kHz. The output signal output from playback device 100 is input to LPF section 200, which outputs a low-pass output signal in which the high-frequency side of this output signal is attenuated. The low-pass output signal is input to the driver unit 11, and the driver unit 11 is driven based on the low-pass output signal. As a result, the driver unit 11 emits an acoustic signal AC2 (second acoustic signal) into the area AR (internal space) of the hollow portion 220, in which frequency band components (for example, band components for which human hearing sensitivity is high, for example, 3 kHz-6 kHz band components) including the above-mentioned predetermined frequency (for example, a band for which human hearing sensitivity is high, for example, 6 kHz) are suppressed. The acoustic signal AC2 (second acoustic signal) emitted into the area AR (internal space) of the hollow portion 220 is further emitted to the outside from the sound hole 123a. Note that the LPF section 200 may be realized by electronic components such as a coil and a capacitor, or may be realized by digital processing. When the LPF section 200 is configured by electronic components such as a resistor and a capacitor, a power supply for driving the LPF section 200 is not required. In this case, the acoustic signal output device 20 may be a wired type that does not require a power supply. The LPF section 200 may be provided outside the housing 12 or may be provided in the housing 12 itself.

[0041] <Design example 5> As shown in FIG. 12B, a switching unit 210 may be further provided that switches between whether driver unit 11 emits acoustic signal AC2 (second acoustic signal) in which frequency band components (for example, band components for which human hearing sensitivity is high, for example, 6 kHz) including the above-mentioned predetermined frequency (for example, a band for which human hearing sensitivity is high, for example, 3 kHz-6 kHz band components) are suppressed into area AR (internal space) of hollow portion 220, or whether driver unit 11 emits acoustic signal AC2 (second acoustic signal) in which frequency band components including this predetermined frequency are not suppressed into area AR (internal space) of hollow portion 220. For example, switching unit 210 switches whether or not to use LPF unit 200 of design example 4. When switched to use LPF unit 200, as described in design example 4, a low-pass output signal that has passed through LPF unit 200 is input to driver unit 11, and driver unit 11 is driven based on this low-pass output signal. On the other hand, when the LPF unit 200 is switched not to be used, the output signal output from the playback device 100 is input directly to the driver unit 11, and the driver unit 11 is driven based on this output signal. By manually operating this switching unit 210, the user can emit acoustic signals AC1 and AC2 with the above-mentioned frequency band components suppressed in environments where sound leakage is a concern, thereby suppressing sound leakage in the high frequency range, and can emit acoustic signals AC1 and AC2 without suppressing the above-mentioned frequency band components in environments where external noise is loud and sound leakage is not a concern. In the latter case, the above-mentioned frequency band components (e.g., band components in which human hearing sensitivity is high, e.g., band components in the 3 kHz to 6 kHz range) are not suppressed, allowing music and voice to be heard even in high-noise environments. The switching unit 210 may be provided outside the housing 12 or may be provided within the housing 12 itself.

[0042] <Design Example 6> Instead of using LPF section 200 in design example 4, the high-frequency components (frequency band components including the above-mentioned specific frequency) of acoustic signal AC2 (second acoustic signal) emitted from driver unit 11 may be suppressed based on the structure of driver unit 11. For example, if the diaphragm of driver unit 11 is a dynamic type with a paper cone, the stiffness sh of the neck of the paper cone can be designed so that the high-frequency reproduction limit frequency fh of the paper cone is the upper limit (for example, 6 kHz or nearby) of the band where human hearing sensitivity is high (for example, the 3 kHz to 6 kHz band component). The high-frequency reproduction limit frequency fh and stiffness sh satisfy the following relationship: fh=(1 / (2π))×√(sh / M) where M is the mass of the vibration system including the cone paper. In other words, the softer the material of the diaphragm of driver unit 11, the lower the high-frequency reproduction limit frequency fh. Furthermore, such a driver unit 11 may be combined with LPF section 200 of design example 4.

[0043] <Experimental Results> 14B illustrates sound pressure levels when the LPF unit 200 is used (with LPF) and when the LPF unit 200 is not used (without LPF). As illustrated in FIG. 14B, it can be seen that by using the LPF unit 200, the sound pressure level in a band where human hearing sensitivity is high (for example, band components of 3 kHz to 6 kHz) is suppressed, and sound leakage can be reduced.

[0044] [Third embodiment] In the third embodiment, the mounting method of the acoustic signal output device described above will be exemplified.

[0045] <Wearing method 1> 15, one end 311 of a curved, rod-shaped ear hook 310 is fixed to the outside of the housing 12. By attaching this ear hook 310 to the auricle, the acoustic signal output device 10 (20) can be worn as shown in FIG. 5. In this example, one end 311 of the ear hook 310 is fixed to the area 132 (second area) side, not the area 131 (first area) side. As a result, the acoustic signal AC1 (first acoustic signal) emitted toward the area 131 side is emitted into the ear canal 1011 without being blocked by the ear hook 310.

[0046] <Wearing method 2> 16A to 16C is an acoustic signal output device 30 in which the support section 13 of the acoustic signal output device 10 (20) is integrated into the temple 33 of the eyeglasses. In this example, a region 131 (first region) of the support section 13 is disposed on the ear hook 33a side (B1 direction side) of the temple 33 that is attached to the auricle 1020, and a region 132 (second region) that protrudes further than the region 131 (first region) is disposed on the lens 34 side (B2 direction side). The region 131 (first region) protrudes inward from the temple 33 (D1 direction) and is configured in a shape that guides the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) toward the region 131 (first region) side (B1 direction side), as described above. When such eyeglasses are worn, region 132 (second region) of support portion 13 is in contact with and supported by some part of the head (body), and region 131 (first region) is positioned on the ear canal 1011 side without the opening end 131b of sound hole 121a (first sound hole) and region 131 (first region) of support portion 13 coming into contact with at least a part of the head (body). Acoustic signal AC1 emitted from sound hole 121a is guided to the ear canal 1021 side (the lower side of pinna 1020) and emitted.

[0047] <Wearing method 3> 17, an acoustic signal output device 3100 of wearing method 3 has a structural unit 2112 including a housing and a support unit, and a wearing unit 2122 configured to hold the structural unit 2112 and be worn on a middle part 1023 of the auricle 1020. The middle part 1023 is the middle part between the upper part 1022 (helix side) and the lower part 1024 (earlobe side) of the auricle 1020. The structural unit 2112 is the housing 12 and the support unit 13 exemplified in the first embodiment, its modified example, or the second embodiment.

[0048] <Wearing method 4> As illustrated in FIG. 18A, the acoustic signal output device 4100 of wearing method 4 has a structural part 2112 including a housing and a support part, and a wearing part 2224 configured to hold the structural part 2112 and be worn on the upper part 1022 of the auricle 1020, which is a part of the auricle 1020.

[0049] <Wearing method 5> As illustrated in Figure 18B, the acoustic signal output device 4100' of wearing method 5 has a structural part 2112 including a housing and a support part, a wearing part 2224 configured to hold the structural part 2112 and be worn on the upper part 1022 of the auricle 1020, which is part of the auricle 1020, and a wearing part 4421 configured to contact the concha cavity 1025 of the auricle 1020.

[0050] <Wearing method 6> The acoustic signal output device 4200 illustrated in FIG. 19 has a structural part 2112, a columnar mounting part 4210 configured to hold the structural part 2112 and be positioned at the base of the auricle 1020 when worn, and an arc-shaped mounting part 4220 held at both ends of the mounting part 4210 and worn in the area from the back side of the upper part 1022 of the auricle 1020 to the lower part 1024.

[0051] <Wearing method 7> The acoustic signal output device 5110 of wearing method 7 illustrated in FIGS. 20A to 20E includes a structural unit 5111 that emits an acoustic signal and a wearing unit 5112 that holds the structural unit 5111 and is hooked onto the back side of the upper portion 1022 of the auricle 1020 when worn. The structural unit 5112 is the housing 12 and support unit 13 illustrated in the first embodiment, its modified example, or the second embodiment. The wearing unit 5112 is a bent rod-shaped member, and the structural unit 5111 is attached to one end of the wearing unit 5112 so as to be rotatable in the R5 direction. The auricle 1020 is sandwiched between the structural unit 5111 and the wearing unit 5112, thereby fixing the acoustic signal output device 5110 to the auricle 1020. Furthermore, because the structural unit 5111 can be rotated in the R5 direction relative to one end of the wearing unit 5112, the wearing position and the position of the sound hole can be adjusted to suit the size and shape of the individual auricle 1020.

[0052] <Wearing method 8> 21A to 21C , an acoustic signal output device 5120 of wearing method 8 has a structural part 5121 that emits an acoustic signal, and a wearing part 5122 that holds the structural part 5121 and is hooked onto the back side of the upper part 1022 of the auricle 1020 when worn. The structural part 5121 is the housing 12 and the support part 13 exemplified in the first embodiment, its modified example, or the second embodiment. Unlike wearing method 7, the structural part 5121 is not rotatable relative to the wearing part 5122. The auricle 1020 is sandwiched between the structural part 5121 and the wearing part 5122, thereby fixing the acoustic signal output device 5120 to the auricle 1020.

[0053] <Wearing Method 9> 22A and 22B show acoustic signal output devices 5130 and 5140 of wearing method 9, each of which has a structural portion 5131 and 5141 that emits an acoustic signal, and a wearing portion 5132 and 5142 that holds the structural portion 5131 and 5141 and is hooked onto the back side of the upper portion 1022 of the auricle 1020 when worn. The structural portions 5131 and 5141 are the housing 12 and the support portion 13 shown in the first embodiment, its modified example, or the second embodiment. Furthermore, the acoustic signal output device 5140 shown in FIG. 22B has a wearing portion 5143 that is configured to come into contact with the cavity of the concha 1025 of the auricle 1020 when worn. This allows for more stable wearing.

[0054] <Wearing method 10> 23A, 23B, and 23C includes a structural unit 5151 that emits an acoustic signal, a rod-shaped mounting unit 5152 that holds the structural unit 5151 and is hooked onto the back side of the upper portion 1022 of the auricle 1020 when worn, a columnar support unit 5154 that holds the structural unit 5151 at one end and the mounting unit 5152 at the other end, a rod-shaped mounting unit 5153 that is hooked onto the back side of the middle portion 1023 and the upper portion 1022 of the auricle 102 from the middle portion 1023 side when worn, and a columnar support unit 5155 that holds the structural unit 5151 at one end and the mounting unit 5153 at the other end. The structural unit 5151 is the housing 12 and support unit 13 shown in the first embodiment, its modified example, or the second embodiment. The auricle 1020 is sandwiched between the structural part 5151 and the attachment parts 5152 and 5153 , and thus the acoustic signal output device 5150 is fixed to the auricle 1020 .

[0055] <Wearing method 12> 24A to 24E includes a structural unit 5161 that emits an acoustic signal, a columnar mounting unit 5164 that holds the structural unit 5161 and is configured to be positioned at the base of the auricle 1020 when worn, a rod-shaped mounting unit 5162 that is held at one end of the mounting unit 5164 and that can be hooked onto the back side of the upper part 1022 of the auricle 1020 when worn, and a rod-shaped mounting unit 5163 that is held at the other end of the mounting unit 5164 and that can be hooked onto the back side of the lower part 1024 of the auricle 1020 when worn. The structural unit 5161 is the housing 12 and support unit 13 shown in the first embodiment, its modified example, or the second embodiment. The pinna 1020 is sandwiched between the structural part 5161 and the mounting part 5164 and the mounting parts 5152 and 5153 , and thus the acoustic signal output device 5160 is fixed to the pinna 1020 .

[0056] <Wearing method 13> 25A to 25D and 26A to 26D each include a structural portion 5171, 5181 that emits an acoustic signal, a columnar mounting portion 5172, 5182 configured to be positioned behind the middle portion 1023 of the auricle 102 when worn, and a curved, strip-shaped support portion 5173, 5183 that holds the structural portion 5171, 5181 at one end and the mounting portion 5172, 5182 at the other end. The structural portion 5171, 5181 is the housing 12 and the support portion 13 illustrated in the first embodiment, its modified example, or the second embodiment. The auricle 1020 is sandwiched between the structural portion 5171, 5181 and the mounting portion 5172, 5182, thereby fixing the acoustic signal output device 5170, 5180 to the auricle 1020.

[0057] <Wearing Method 14> 27A to 27C includes a structural unit 5191 that emits an acoustic signal, and a rod-shaped mounting unit 5192 that holds the structural unit 5191 and is configured to be positioned behind the auricle 102 when worn. The structural unit 5191 is the housing 12 and support unit 13 shown in the first embodiment, its modified example, or the second embodiment. The mounting unit 5192 holds the structural unit 5191 at one end that is positioned on the lower part 1024 of the auricle 1020 when worn. The auricle 1020 is sandwiched between the structural unit 5191 and the mounting unit 5192, thereby fixing the acoustic signal output device 5190 to the auricle 1020.

[0058] <Wearing method 15> 28A to 28E includes a structural unit 5201 that emits an acoustic signal and an annular mounting unit 5202 that holds the structural unit 5201. The structural unit 5201 is the housing 12 and the support unit 13 shown in the first embodiment, its modified example, or the second embodiment. When worn, the auricle 1020 is inserted into the annular mounting unit 5202, and the mounting unit 5202 is disposed behind the upper portion 1022, middle portion 1023, and lower portion 1024 of the auricle 1020. At this time, the auricle 1020 is sandwiched between the structural unit 5201 and the mounting unit 5202, thereby fixing the acoustic signal output device 5200 to the auricle 1020.

[0059] <Wearing Method 16> 29A, a structural unit 5251 may be fixed to a rod-like attachment unit 5352 that is curved into a shape so as to be attached to the back of the head and the pinna 1020 of the user 1000. The structural unit 5251 is the housing 12 and the support unit 13 exemplified in the first embodiment, its modified example, or the second embodiment. This attachment unit 5352 is attached to the back of the head and the pinna 1020 of the user 1000, and the housing 12 and the support unit 13 are arranged as described above.

[0060] <Wearing Method 17> 29B includes the above-mentioned driver unit 11 (not shown), a substantially spherical housing 5612 (structural portion) that houses the driver unit 11 inside, a substantially spherical attachment portion 5601 that is placed on the auricle when worn, and a curved portion 5602 that is an elastic body that connects the housing 5612 and the attachment portion 5601. Housing 5612 is provided with sound hole 121a (first sound hole) that emits (derives) to the outside an acoustic signal AC1 (first acoustic signal) emitted from driver unit 11, and sound hole 123a (second sound hole) that emits (derives) to the outside an acoustic signal AC2 (second acoustic signal) emitted from driver unit 11. Here, the device may be designed so that the sound pressure level of acoustic signal AC2 emitted to the outside from sound hole 123a increases as the distance from sound hole 121a increases. When the acoustic signal output device 5600 is worn, the housing 5312 is placed on the front side of the auricle (the ear canal side) with the sound hole 121a facing the ear canal, and the attachment part 5601 is placed on the back side of the auricle (the side where the ear canal does not exist), and the auricle is sandwiched between the housing 5312 and the attachment part 5601.

[0061] [Fourth embodiment] In this embodiment, an acoustic signal output device of a type that is partly fitted into the ear canal but does not completely seal the ear canal will be exemplified.

[0062] <Example 4-1> As illustrated in Figures 30A to 30C, the acoustic signal output device 5300 of this example has the above-mentioned driver unit 11, a housing 5312 (structural part) that houses the driver unit 11 inside, and a support part 5313 (structural part) that is placed in the user's ear canal when worn.

[0063] <Chassis 5312> Housing 5312 is a hollow member with an outer wall, and houses driver unit 11 inside. For example, driver unit 11 is fixed to the end of housing 5312 on the D1 direction side. However, this does not limit the present invention. There are also no limitations on the shape of housing 5312.

[0064] <Sound holes 121a, 123a> The wall of the housing 5312 is provided with a sound hole 121a (first sound hole) that emits (derives) to the outside an acoustic signal AC1 (first acoustic signal) emitted from the driver unit 11, and a sound hole 123a (second sound hole) that emits (derives) to the outside an acoustic signal AC2 (second acoustic signal) emitted from the driver unit 11.

[0065] In this example, sound hole 121a (first sound hole) is provided in region AR1 (first region) of a wall portion disposed on one side of driver unit 11 (the D1 direction side, which is the side from which acoustic signal AC1 is emitted). Sound hole 121a in this example is disposed at an eccentric position displaced in direction B1 (first direction) from axis A1 (central axis of the structural portion), and opens toward direction D1. Note that axis A1 is an axis that passes through the central region of housing 5312 and extends in direction D1, and direction B1 is a specific radiation direction centered on axis A1. In this example, for simplicity of explanation, an example is shown in which the edge shape of the open end of sound hole 121a is elliptical (the open end is elliptical). However, this does not limit the present invention. For example, the edge shape of sound hole 121a may be circular, rectangular, triangular, or another shape. Furthermore, the end of sound hole 121a may be mesh-like. In other words, the end of sound hole 121a may be configured with a plurality of holes. Also, in this example, for the sake of simplicity of explanation, an example is shown in which one sound hole 121a is provided in area AR1 (first area) of the wall of housing 5312. However, this does not limit the present invention. For example, two or more sound holes 121a may be provided in area AR1 (first area) of the wall of housing 5312.

[0066] In this example, sound hole 123a (second sound hole) is provided in region AR3 of wall 123, which is in contact with the region between region AR1 of the wall of housing 5312 and region AR2 of the wall arranged on the D2 direction side of driver unit 11 (the other side from which acoustic signal AC2 is emitted). Furthermore, sound hole 123a (second sound hole) in this example is arranged biased toward the B2 direction (second direction) side. B2 direction (second direction) is a direction that includes a component in the opposite direction of B1 direction (first direction). Specific examples of such an arrangement are as exemplified in the above-described embodiments and their modified examples. Furthermore, the design is such that the sound pressure level of acoustic signal AC2 emitted to the outside from sound hole 123a increases as the distance from sound hole 121a increases. Specific examples of such an arrangement are as exemplified in the above-described embodiments and their modified examples.

[0067] <Support Department 5313> The support portion 5313 is a convex portion provided on the outer surface of the wall portion on the D1 direction side of the housing 5312. At least a part of the outer surface area of ​​the support portion 5313 has a convex shape. The outer surface area of ​​the support portion 5313 is an outer surface area surrounding the opening end 131b of the sound hole 121a (first sound hole). The outer surface area of ​​the support portion 5313 includes an area 53131 (first area) and an area 53132 (second area) that protrudes beyond the area 53131 (first area). Here, the outer surface area of ​​the support portion 5313 may be configured in a shape that guides the acoustic signal AC1 (first acoustic signal) emitted from the sound hole 121a (first sound hole) toward the area 53131 (first area). In this example, the support portion 5313 including the region 53131 and the region 53132 is provided on the B1 direction side, and the support portion 5313 is not provided in the region 5314 on the B2 direction side including the opposite direction component.

[0068] <Wearing state> The difference from the first embodiment is that when the acoustic signal output device 5300 is worn, the tip of the housing 5312 on the support section 5313 side is inserted into the user's ear canal. When the tip of the housing 5312 is inserted into the ear canal, the region 5314 on the B2 side where the support section 5313 is not provided comes into contact with the inside of the ear canal. The region 53132 (second region) of the support section also comes into contact with the inside of the ear canal. Meanwhile, the region 53131 (first region) of the support section does not come into contact with the inside of the ear canal. Therefore, a gap is formed between the region 53131 and the inside of the ear canal, which prevents the ear canal from being sealed. This has the advantage that the user can easily hear external sounds. On the other hand, part of the acoustic signal AC1 emitted from the open end 131b of the sound hole 121a is emitted to the outside through the gap between the region 53131 and the inside of the ear canal. The acoustic signal AC1 emitted to the outside in this manner is perceived as sound leakage. However, as described in the first embodiment, this acoustic signal AC1 is canceled out by the acoustic signal AC2 emitted from the sound hole 123a, thereby suppressing sound leakage. Furthermore, because the sound hole 123a in this example is positioned biased toward the B2 direction, the acoustic signal AC2 emitted from the sound hole 123a is less likely to enter the ear canal through the gap between the region 53131 and the inside of the ear canal. Therefore, the acoustic signal AC1 is not significantly canceled out in the ear canal, allowing the user to hear the acoustic signal AC1 with sufficient sound quality. A battery case for storing and charging the acoustic signal output device 5300 may be provided. In this case, the battery case may be designed according to the convex shape of the support unit. For example, the area in contact with the convex shape when the acoustic signal output device 5300 is stored in the battery case may be designed deeper than the other areas in the support unit. If the convex shape is made of a material that allows the shape to be changed, the convex shape may be designed to be, for example, a predetermined size smaller than the size including the convex shape so that the convex shape will hold the acoustic signal output device 5300 in the battery case when the acoustic signal output device 5300 is stored in the battery case.

[0069] <Example 4-2> In Example 4-1, support portion 5313 is provided on the B1 direction side of the outer surface of the wall portion on the D1 direction side of housing 5312, and no support portion is provided in region 5314 on the B2 direction side, which includes the opposite direction component ( FIG. 30A ). However, a protruding region surrounding open end 131b of sound hole 121a may be provided in region 5314. This protruding region surrounding open end 131b is, for example, an annular convex region surrounding the B2 direction side of open end 131b. Preferably, when acoustic signal output device 5300 is worn, most or all of this annular convex region surrounding the B2 direction side of open end 131b comes into contact with the inside of the ear canal, and it is desirable that acoustic signal AC1 emitted from open end 131b of sound hole 121a leaks as little as possible in the B2 direction.

[0070] <Example 4-3> Instead of providing the support section 5313 of Example 4-1, a sound hole 53123b (for example, a through-hole) may be provided on the outer surface of the wall section on the D1 direction side of the housing 5312, as in an acoustic signal output device 5400 illustrated in Fig. 31A to Fig. 31C. The sound hole 53123b takes in external sound into the ear canal and emits to the outside the acoustic signal AC1 emitted inside the housing 5312. In this example, the sound hole 53123b is provided on the B1 direction side, and no sound hole 53123b is provided in an area 5314 on the B2 direction side that includes the opposite direction component.

[0071] When the tip of the housing 5312 is inserted into the ear canal during wearing of the acoustic signal output device 5400, the tip of the housing 5312 contacts the inside of the ear canal. Furthermore, the sound hole 53123b is positioned on the outside of the ear canal, which prevents the ear canal from being sealed. This has the advantage of allowing the user to easily hear external sounds. On the other hand, a portion of the acoustic signal AC1 emitted from the open end 131b of the sound hole 121a is emitted to the outside through the sound hole 53123b. The acoustic signal AC1 thus emitted to the outside is perceived as sound leakage, but as described in the first embodiment, this acoustic signal AC1 is canceled out by the acoustic signal AC2 emitted from the sound hole 123a, thereby suppressing sound leakage. Furthermore, since the sound hole 123a in this example is positioned biased toward the B2 direction, the acoustic signal AC2 emitted from the sound hole 123a is less likely to enter the ear canal through the sound hole 53123b. Therefore, the acoustic signal AC1 is not significantly canceled out in the ear canal, and the user can hear the acoustic signal AC1 with sufficient sound quality.

[0072] <Example 4-4> As illustrated in FIGS. 32A and 32B, acoustic signal output device 5500 of this example has driver unit 11 described above and housing 5512 (structural section) that houses driver unit 11. Housing 5512 has insertion section 5512a that is inserted into the ear canal when worn, and external placement section 5512b that is placed somewhere on the auricle. Insertion section 5512a is provided with through-hole 55121 that passes through insertion section 5512a. As a result, even when insertion section 5512a is inserted into the ear canal, the ear canal is open to the outside through through-hole 55121 and is not sealed. Note that although the external shape of insertion section 5512a in FIGS. 32A and 32B is a donut shape with through-hole 55121, insertion section 5512a may have another shape with through-hole 55121 (for example, a prismatic shape or a triangular prism shape with through-hole 55121). One side of insertion portion 5512a (the side inserted into the ear canal when worn: the D1 direction side) is provided with one or more sound holes 121a (first sound holes). Furthermore, the other side (the D2 direction side) of insertion portion 5512a is provided with one or more sound holes 123a (second sound holes). As described above, sound hole 121a emits acoustic signal AC1 emitted from driver unit 11 to the outside, and sound hole 123a emits acoustic signal AC2 emitted from driver unit 11 to the outside. Furthermore, the design may be such that the sound pressure level of acoustic signal AC2 emitted to the outside from sound hole 123a increases the farther the space is from sound hole 121a. Specific examples of such an arrangement are as exemplified in the above-mentioned embodiments and their modified examples.

[0073] When the acoustic signal output device 5500 is worn, the insertion portion 5512a of the housing 5512 is inserted into the ear canal, and the external placement portion 5512b is placed somewhere on the pinna. The through-hole 55121 of the insertion portion 5512a does not seal the ear canal. This has the advantage of making it easier for the user to hear external sounds. On the other hand, a portion of the acoustic signal AC1 emitted from the open end 131b of the sound hole 121a is emitted to the outside from the through-hole 55121. The acoustic signal AC1 thus emitted to the outside is perceived as sound leakage, but as described in the first embodiment, this acoustic signal AC1 is canceled out by the acoustic signal AC2 emitted from the sound hole 123a, thereby suppressing sound leakage.

[0074] <Example 4-5> Any of Example 4-1 to Example 4-4 may be combined with Design Examples 1 to 6 of the second embodiment. That is, in any of Examples 4-1 to 4-4, the resonant frequency of the hollow portion of housings 5312, 5512 may be designed to be equal to or higher than a predetermined frequency (for example, equal to or higher than a band where human hearing sensitivity is high, for example, 6 kHz or higher), and acoustic signal AC2 (second acoustic signal) in which frequency band components including the predetermined frequency (for example, band components where human hearing sensitivity is high, for example, band components of 3 kHz to 6 kHz) are suppressed may be designed to be emitted to the outside from sound hole 123a (second sound hole).

[0075] <Example 4-6> 33, a structural unit 5781 may be fixed to a rod-like attachment unit 5782 that is curved into a shape so as to be worn on the shoulder or neck of a user 1000. The structural unit 5781 is, for example, any one of the acoustic signal output devices 5300, 5400, and 5500 of Examples 4-1 to 4-5.

[0076] [Other variations] The present invention is not limited to the above-described embodiments. For example, in the above-described embodiments, the housing 12 and the support part 13 are separate bodies, but the housing 12 and the support part 13 may be integrally configured.

[0077] In the first embodiment, the housing 12 does not necessarily have to be provided with the sound hole 123a. Even in this case, when the housing 12 and the support unit 13 (structural unit) are attached to the pinna 1010 of the user 1000, the region 132 (second region) of the support unit 13 comes into contact with and is supported by some part of the pinna 1010 (body), and the opening end 131b of the sound hole 121a (first sound hole) and the region 131 (first region) of the support unit 13 do not come into contact with at least a part of the pinna 1010 (body), and the region 131 (first region) is positioned on the ear canal 1011 side. In this case, the region 131 comes into contact with the pinna 1010 and acts as a support, providing a high sense of stability when worn. Furthermore, the B2 side of the opening end 131b of the sound hole 121a is surrounded by the region 132, so that the acoustic signal AC1 emitted from the sound hole 121a can be prevented from leaking in the B2 direction (sound leakage). In the second embodiment, the support portion 13 does not necessarily have to be provided.

[0078] Furthermore, in each of the above-described embodiments, driver unit 11 is housed inside housing 12. However, driver unit 11 may be disposed outside housing 12, and acoustic signals AC1 and AC2 emitted from driver unit 11 may be introduced into housing 12 through a waveguide. [Explanation of symbols]

[0079] 10,20,30,3100,4100,4200,5110,5120,5130,5140,5150,5160,5170,5190,5200-5600 Acoustic signal output device 5021,5111,5112,5121,5131,5151,5171,5191,5201,5781 Structural part 121a,123a sound hole 11 Driver unit 210 Switching section 220 Hollow part 241 Internal hollow part 1000 users 1010,1020 Auricle 1011,1021 External auditory canal

Claims

1. a first sound hole or holes for emitting a first acoustic signal to the outside is provided, and at least a part of an outer surface area surrounding an open end of the first sound hole has a structure having a convex shape; the outer surface region includes a first region and a second region protruding beyond the first region, an open end of the first sound hole faces a space surrounded by the second area, the first region side of the space surrounded by the second region is open outward from the outer periphery of the space surrounded by the second region, When the structure is attached to the auricle, the first region is disposed below the auricle relative to the second region, The outer surface area is configured in a shape that guides the first acoustic signal emitted from the first sound hole toward an ear canal.

2. The acoustic signal output device of claim 1, an open end of the first sound hole faces a space partially surrounded by the second region, An acoustic signal output device, wherein the first region side of the space partially surrounded by the second region is open to the ear canal side outside the outer periphery of the space partially surrounded by the second region.

3. The acoustic signal output device of claim 2, an open end of the first sound hole faces a space partially surrounded by the curved second region, An acoustic signal output device, wherein the first region side of the space partially surrounded by the curved second region is open to the ear canal side outside the outer periphery of the space partially surrounded by the curved second region.

4. 2. The acoustic signal output device of claim 1, When the structure is attached to the body, the second region is supported in contact with any part of the body; the open end of the first sound hole and at least a part of the first region do not come into contact with the body, The first region is disposed on the ear canal side. The acoustic signal output device is configured as follows.

5. 5. The acoustic signal output device according to claim 1, the structure is further provided with one or more second sound holes for emitting a second acoustic signal to the outside, an open end of the second sound hole faces a space outside the space surrounded by the second region, 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 a predetermined value smaller than the attenuation rate of the acoustic signal at the second point relative to the first point due to air propagation; Is designed to be: an attenuation amount of the first acoustic signal at the second point relative to the first point, a predetermined value greater than the attenuation of the acoustic signal due to air propagation at the second point relative to the first point; An acoustic signal output device designed to satisfy the above.

6. 2. The acoustic signal output device of claim 1, When the structure is attached to the body, An acoustic signal output device designed so that the sound pressure level of the first acoustic signal emitted from the structural part toward the ear canal is higher than the sound pressure level of the first acoustic signal emitted from the structural part toward a side other than the ear canal.

Images