Acoustic lens and loudspeaker system
The acoustic lens with dual control mechanisms for sound wave directivity addresses sound leakage issues in speaker systems by managing sound propagation in multiple directions, ensuring focused audio delivery.
Patent Information
- Application Number
- CN202380038245.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-04-27
- Filing Date
- 2023-05-08
- Publication Date
- 2024-12-27
AI Technical Summary
Existing speaker systems installed in vehicles and other moving bodies face issues with sound leakage to unintended directions, lacking effective control over sound wave directivity in multiple intersecting directions.
An acoustic lens with multiple partitions that include a first control mechanism for controlling directivity in one direction and a second control mechanism for controlling directivity in a direction intersecting the first, utilizing partitions of varying lengths and angles to manage sound wave propagation.
The acoustic lens effectively controls sound wave directivity in two intersecting directions, reducing sound leakage to unintended recipients and enhancing audio focus on the intended user.
Smart Images
Figure CN119213788A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to an acoustic lens and a speaker system for controlling the directivity of sound. Background Art
[0002] Patent Document 1 discloses an acoustic lens that improves the directional direction of sound waves to only one predetermined direction.
[0003] Prior art literature
[0004] Patent Literature
[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 63-73297 Summary of the invention
[0006] Problems to be solved by the invention
[0007] An object of the present disclosure is to provide an acoustic lens or the like that can easily control the directivity of sound waves in each of two directions that intersect each other.
[0008] Means for solving problems
[0009] An acoustic lens of one embodiment of the present disclosure includes an opening and a plurality of partitions. Sound waves emitted from a speaker are input to the opening. The plurality of partitions constitute a plurality of sound channels through which the sound waves input to the opening pass. The plurality of partitions have a first control mechanism and a second control mechanism. The first control mechanism controls the directivity in a first direction of the sound waves output to the outside through the plurality of sound channels. The second control mechanism controls the directivity in a second direction intersecting the first direction of the sound waves output to the outside through the plurality of sound channels.
[0010] Moreover, a speaker system according to one aspect of the present disclosure includes: the acoustic lens; and the speaker that emits the sound wave to the opening of the acoustic lens.
[0011] Effects of the Invention
[0012] According to the present disclosure, there is an advantage that the directivity of sound waves can be easily controlled in each of two directions intersecting with each other. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 1 is a schematic diagram showing a speaker system of a comparative example.
[0014] Figure 2 This is a schematic diagram showing an example of use of the speaker system including the acoustic lens according to the first embodiment.
[0015] Figure 3 This is a schematic diagram showing the structure of the acoustic lens according to the first embodiment.
[0016] Figure 4 This is an explanatory diagram of the first control mechanism of the acoustic lens according to the first embodiment.
[0017] Figure 5 This is an explanatory diagram of the second control mechanism of the acoustic lens according to the first embodiment.
[0018] Figure 6 This is an explanatory diagram of the directivity of the acoustic lens in the first direction according to the first embodiment.
[0019] Figure 7 This is an explanatory diagram of the directivity in the second direction of the acoustic lens according to the first embodiment.
[0020] Figure 8 This is a schematic diagram showing the configuration of a speaker system including an acoustic lens according to a second embodiment.
[0021] Fig. 9 This is a partially cutaway perspective view of a speaker system according to Embodiment 2.
[0022] Fig.10 This is a top view of the speaker system according to the second embodiment.
[0023] Fig.11 This is a schematic diagram showing the configuration of an acoustic lens according to a modified example of the first embodiment. DETAILED DESCRIPTION
[0024] (Insights that form the basis of this disclosure)
[0025] Conventionally, there is known a speaker system which is installed in a seat of a moving body such as a car, an airplane, or a train, and which plays sound, music, etc. to a user sitting in the seat. Figure 1 2 is a schematic diagram showing a speaker system 200 of a comparative example. The speaker system 200 of the comparative example is installed in the headrest 31 of the seat 3. Figure 1 In the illustrated example, the speaker system 200 of the comparative example is installed near the left ear and near the right ear of the user U1 sitting at the seat 3 .
[0026] Here, in the speaker system 200 of the comparative example, the directivity of the sound waves emitted from the speaker is the same with respect to the front direction of the speaker. Therefore, in the speaker system 200 of the comparative example, the sound or music played by the speaker is likely to leak to the person sitting in the seat adjacent to the seat 3 and the person sitting in the seat behind the seat 3. That is, in the speaker system 200 of the comparative example, there is a problem that the sound is likely to leak to other than the target user U1.
[0027] In view of the above situation, in the present disclosure, the structure of the acoustic lens is studied with the aim of providing an acoustic lens, etc., which can easily control the directivity of sound waves in each of two mutually intersecting directions, thereby easily suppressing sound leakage to other than the target user U1.
[0028] More specifically, the acoustic lens of the first mode of the present disclosure includes an opening and a plurality of partitions. Sound waves emitted from a speaker are input to the opening. The plurality of partitions constitute a plurality of sound channels through which the sound waves input to the opening pass. The plurality of partitions have a first control mechanism and a second control mechanism. The first control mechanism controls the directivity in a first direction of the sound waves output to the outside through the plurality of sound channels. The second control mechanism controls the directivity in a second direction intersecting the first direction of the sound waves output to the outside through the plurality of sound channels.
[0029] This has the advantage that the directivity of the sound wave in the first direction is controlled by the first control mechanism, and the directivity of the sound wave in the second direction is controlled by the second control mechanism, so it is easy to control the directivity of the sound wave in each of the two intersecting directions.
[0030] In addition, for example, in the acoustic lens of the second mode of the present disclosure, in the first mode, the first control mechanism is composed of a plurality of first partition plates arranged along the first direction and having different lengths in the direction of travel of the sound wave among the plurality of partition plates. The second control mechanism is composed of a plurality of second partition plates arranged along the second direction and having different lengths in the direction of travel of the sound wave among the plurality of partition plates.
[0031] Thus, there is an advantage that by making the distances between the multiple sound channels formed by the multiple first partitions different from each other, it is easy to control the directivity of the sound wave in the first direction. In addition, there is an advantage that by making the distances between the multiple sound channels formed by the multiple second partitions different from each other, it is easy to control the directivity of the sound wave in the second direction.
[0032] Furthermore, for example, in the acoustic lens of the third aspect of the present disclosure, in the second aspect, the lengths of the plurality of first partition plates in the direction in which the sound wave travels become shorter from one direction toward the other direction in the first direction.
[0033] This has the advantage of easily controlling the directivity of the sound wave so that one side of the first direction has the directivity.
[0034] Furthermore, for example, in the acoustic lens of the fourth aspect of the present disclosure, in the second or third aspect, the length of the plurality of second partition plates in the direction in which the sound wave travels becomes shorter as they are farther away from the center in the second direction.
[0035] This has the advantage of easily making the center side of the second direction of the sound wave have directivity.
[0036] Furthermore, for example, in an acoustic lens according to a fifth aspect of the present disclosure, in any one of the second to fourth aspects, at least one of the plurality of first partition plates and the plurality of second partition plates is inclined at a predetermined angle with respect to a propagation direction of sound waves.
[0037] This has the advantage that the directivity of the sound wave can be easily controlled by adjusting a predetermined angle.
[0038] Furthermore, for example, in the acoustic lens according to a sixth aspect of the present disclosure, in the fifth aspect, the predetermined angles are different in the respective partition plates.
[0039] This has an advantage that the directivity of sound waves can be easily controlled even if the lengths of the partition plates are not made different from each other.
[0040] Furthermore, for example, in the acoustic lens of the seventh aspect of the present disclosure, in any one of the second to sixth aspects, the first direction and the second direction are orthogonal to each other.
[0041] Therefore, for example, if the first direction is set as the horizontal direction and the second direction is set as the vertical direction, there is an advantage that the directivity of the sound wave can be easily controlled in each of the horizontal direction and the vertical direction.
[0042] In addition, for example, in the acoustic lens of the eighth aspect of the present disclosure, in the first aspect, the plurality of partitions are a plurality of third partitions arranged along the first direction. The first control mechanism is configured by having the plurality of third partitions having different lengths in the direction of travel of the sound wave and being inclined at a first angle relative to the direction of travel of the sound wave. The second control mechanism is configured by having the plurality of third partitions being inclined at second angles different from each other relative to the second direction and being arranged in a line-symmetrical manner across the center in the second direction when viewed from the direction of travel of the sound wave.
[0043] This has the advantage that the directivity of the sound wave in the first direction is controlled by the first control mechanism, and the directivity of the sound wave in the second direction is controlled by the second control mechanism, so it is easy to control the directivity of the sound wave in each of the two intersecting directions.
[0044] Moreover, for example, a speaker system according to a ninth aspect of the present disclosure includes the acoustic lens according to any one of the first to eighth aspects and a speaker that emits sound waves to an opening of the acoustic lens.
[0045] This has the advantage of being able to produce the same effect as the above-mentioned acoustic lens.
[0046] Hereinafter, the embodiments are described in detail with reference to the accompanying drawings. In addition, the embodiments described below all represent general or specific examples. The numerical values, shapes, materials, constituent elements, configuration positions of constituent elements, connection methods, steps, or the order of steps shown in the following embodiments are examples and do not limit the main purpose of the present disclosure. In addition, sometimes geometric expressions such as parallel or orthogonal are used, but these expressions do not represent strict mathematical meanings and include errors or deviations that are substantially allowed. For example, in the following description, if the angle formed by two directions intersecting each other is 90 degrees ± 1 to 5%, it can be said that the two directions are orthogonal. In addition, expressions such as simultaneous or identical also include substantially allowed ranges.
[0047] In addition, among the constituent elements in the following embodiments, constituent elements not described in the independent claims are described as arbitrary constituent elements. In addition, each figure is a schematic diagram and may not be a strict illustration. In addition, in each figure, substantially the same constituent elements are marked with the same reference numerals, and repeated descriptions are sometimes omitted or simplified.
[0048] (Implementation Method 1)
[0049] [1. Composition]
[0050] Hereinafter, the acoustic lens 1 according to the first embodiment and the speaker system 100 including the acoustic lens 1 will be described. Figure 2 1 is a schematic diagram showing an example of using the speaker system 100 including the acoustic lens 1 according to the first embodiment. Figure 2 In the figure, the speaker 2 is omitted. Figure 3 This is a schematic diagram showing the structure of the acoustic lens 1 according to the first embodiment. Figure 3 (a) Figure 3 (b) and Figure 3 (c) are stereoscopic views of the acoustic lens 1 observed from different angles. Figure 4 It is an explanatory diagram of a first control mechanism (described later) of the acoustic lens 1 according to the first embodiment. Figure 5 It is an explanatory diagram of a second control mechanism (described later) of the acoustic lens 1 according to the first embodiment.
[0051] like Figure 2 As shown, the speaker system 100 includes an acoustic lens 1 and a speaker 2 (see Figure 4 and Figure 5 The speaker system 100 is used to allow the target user U1 to listen to the sound wave W1 emitted from the speaker 2 and radiated through the acoustic lens 1 (see Figure 4 as well as Figure 5 ) system.
[0052] In Embodiment 1, the speaker system 100 is provided at seats 3 and 3A of a mobile body such as a car. Hereinafter, the case where seat 3 is a driver's seat of the car and seat 3A is a passenger seat of the car will be described. Seats 3 and 3A are arranged along the left-right direction (horizontal direction) of the car at the front side of the car. Hereinafter, the left-right direction (horizontal direction) of the car will be described as a "first direction d1". In addition, the height direction (vertical direction) of the car will be described as a "second direction d2".
[0053] The speaker systems 100 are respectively provided at both ends in the first direction d1 of the headrest 31 of the seat 3. That is, the speaker systems 100 are respectively provided near the left ear and near the right ear of the user U1 sitting on the seat 3. In addition, the speaker systems 100 are respectively provided at both ends in the first direction d1 of the headrest 31A of the seat 3A. That is, the speaker systems 100 are respectively provided near the left ear and near the right ear of the user U2 sitting on the seat 3A.
[0054] The speaker 2 is a device that outputs a sound wave W1 by converting an electrical signal such as a sound signal into vibration of a vibration plate. The size, shape or structure of the vibration plate, magnetic circuit or frame, etc. constituting the speaker 2 is not particularly limited. In Embodiment 1, the speaker 2 is an electrodynamic speaker having a conical vibration plate. The speaker 2 emits a sound wave W1 to the opening 10 (described later) of the acoustic lens 1. As a result, the sound wave W1 emitted from the speaker 2 passes through the acoustic lens 1 and is radiated to the outside (the atmosphere).
[0055] like Figure 3 As shown, the acoustic lens 1 includes an opening 10 and a plurality of partition plates 11 .
[0056] The opening 10 is a portion into which the sound wave W1 emitted from the speaker 2 is input. Specifically, the opening 10 is a bottom portion of the acoustic lens 1 that faces the speaker 2 and is formed in a lattice shape by combining a plurality of partition plates 11. The sound wave W1 emitted from the speaker 2 passes through a plurality of gaps provided between the partition plates 11 at the opening 10.
[0057] Each partition plate 11 is a flat plate and is a member that is difficult to vibrate. The material constituting each partition plate 11 is, for example, wood, resin, metal, or ceramic, etc., and is not particularly limited. Figure 4 and Figure 5 As shown, the plurality of partition plates 11 constitute a plurality of sound channels P1 through which the sound waves W1 input to the opening 10 pass. In Embodiment 1, the space between the adjacent partition plates 11 becomes the sound channels P1 through which the sound waves W1 input to the opening 10 pass. Furthermore, the sound waves W1 input to the opening 10 are output to the outside through the sound channels P1.
[0058] The plurality of partition plates 11 have a first control mechanism and a second control mechanism. The first control mechanism is a mechanism for controlling the directivity in a first direction d1 of the sound wave W1 output to the outside through the plurality of sound channels P1. Figure 4 As shown, the first control mechanism controls the directivity of the sound wave W1 so that the sound pressure level of the sound wave W1 output to the outside through the acoustic lens 1 is equal to that of the other side ( Figure 4 User U2 side) compared to one side ( Figure 4 The second control mechanism is a mechanism for controlling the directivity of the sound wave W1 output to the outside through the plurality of channels P1 in a second direction d2 intersecting the first direction d1. In the first embodiment, as Figure 5 As shown, the second control mechanism controls the directivity of the sound wave W1 so that the sound pressure level of the sound wave W1 output to the outside through the acoustic lens 1 is equal to the end side ( Figure 5 The upper and lower sides of the center are relatively higher than those of the center, so that the directivity becomes biased toward the center in the second direction d2.
[0059] Here, as described above, in Embodiment 1, the first direction d1 is a horizontal direction and the second direction d2 is a vertical direction. Therefore, in Embodiment 1, the first direction d1 and the second direction d2 are orthogonal to each other. In addition, the first direction d1 and the second direction d2 may cross each other or may not be orthogonal to each other.
[0060] In the first embodiment, the first control mechanism is composed of a plurality of first partition plates 111 among the plurality of partition plates 11. Figure 3 and Figure 4 As shown, the plurality of first partition plates 111 are arranged along the first direction d1, and the lengths l1 in the traveling direction of the sound wave W1 are different from each other. Moreover, the plurality of first partition plates 111 are arranged along the first direction d1 according to the length l1 in the traveling direction of the sound wave W1. Figure 4 to the right) towards the other side ( Figure 4 In other words, the plurality of first partition plates 111 are arranged so that the length l1 of the first partition plate 111 in the traveling direction of the sound wave W1 becomes longer the closer it is to the side where the sound wave W1 is desired to have directivity in the first direction d1.
[0061] Here, the "propagation direction of the sound wave W1" is the propagation direction of the sound wave W1 emitted from the speaker 2, not the propagation direction of the sound wave W1 passing through the acoustic lens 1. In Embodiment 1, the propagation direction of the sound wave W1 corresponds to a direction orthogonal to both the first direction d1 and the second direction d2.
[0062] In the first embodiment, the first partition plates 111 located closest to each other in the first direction d1 ( Figure 4 The two first partition plates 111 (on the right side in FIG. 1 ) deviate from the above conditions, but these first partition plates 111 may also be configured according to the above conditions.
[0063] In addition, in embodiment 1, if Figure 3 and Figure 4 As shown, the plurality of first partition plates 111 are inclined at a predetermined angle θ relative to the traveling direction of the sound wave W1. The predetermined angle θ is an acute angle, for example, 45±1 to 5 degrees. In addition, the predetermined angle θ can be an acute angle, and as an example, it can also be 30±1 to 5 degrees, or 60±1 to 5 degrees.
[0064] In the first embodiment, the second control mechanism is composed of a plurality of second partition plates 112 among the plurality of partition plates 11. Figure 3 and Figure 5 As shown, the plurality of second partition plates 112 are arranged along the second direction d2, respectively, and the lengths l2 in the traveling direction of the sound wave W1 are different from each other. Moreover, the plurality of second partition plates 112 are arranged under the condition that the length l2 in the traveling direction of the sound wave W1 becomes shorter as it moves away from the center of the second direction d2. In other words, the plurality of second partition plates 112 are arranged so that the closer they are to the side where the sound wave W1 is desired to have directivity in the second direction d2, the longer the length l2 of the second partition plate 112 in the traveling direction of the sound wave W1 becomes.
[0065] Here, use Figure 4 The control of the directivity of the sound wave W1 in the first direction d1 by the first control mechanism (plural first partition plates 111) is described. Figure 4 As shown, the lengths of the sound waves W1 of the plurality of sound channels P1 formed by the plurality of first partition plates 111 in the traveling direction (hereinafter referred to as “distance”) increase with the increase in the distance from one side in the first direction d1 ( Figure 4 to the right) towards the other side ( Figure 4 Furthermore, the sound wave W1 passes through each sound path P1 and is radiated to the outside (the atmosphere).
[0066] Here, if Figure 4 As shown, in the first control mechanism, the passage distance of the sound wave W1 is changed by the length of each first partition plate 111 with respect to the position of the ear of the user U1 sitting on the seat 3 and the ear of the user U2 sitting on the seat 3A, and the arrival time of the sound wave W1 is staggered, thereby controlling the directivity in the first direction d1.
[0067] Specifically, as shown by the dotted line, the first direction d1 is reached ( Figure 4The sound wave W1 of the ear of the user U1 (on the right side in the image) is hardly blocked by the first partitions 111 from passing through one side in the first direction d1. Therefore, there is no big difference in the passing distance of the sound wave W1 radiated from each sound channel P1 separated by each first partition 111 of the acoustic lens 1, and the difference in arrival time of the sound wave W1 from each sound channel P1 is small, so the cancellation of the sound wave W1 caused by the difference in arrival time is also small.
[0068] On the other hand, as shown by the one-dot chain line, the other side ( Figure 4 The sound wave W1 of the ear of the user U2 (on the left side in the figure) is blocked by each first partition plate 111 from passing through to the other side in the first direction d1, and is more significantly blocked as it moves toward one side in the first direction d1.
[0069] Therefore, the sound wave W1 heading toward the ear of the user U2 on the other side located in the first direction d1 has a large difference in arrival time due to the large difference in the travel distances of the sound wave W1 radiated from each sound channel P1 separated by each first partition plate 111 of the acoustic lens 1, and the effect of the cancellation of the sound wave W1 caused by the difference in arrival time is large.
[0070] Therefore, the sound pressure level of the sound wave W1 reaching the ear of the user U1 becomes relatively higher than the sound pressure level of the sound wave W1 reaching the ear of the user U2 , and thus has directivity biased toward one side in the first direction d1 .
[0071] In Embodiment 1, as described above, the plurality of first partition plates 111 are each inclined at a predetermined angle θ relative to the traveling direction of the sound wave W1. Therefore, in Embodiment 1, the sound wave W1 is further deflected toward one side in the first direction d1 ( Figure 4 In addition, the directivity of the sound wave W1 in the first direction d1 can be adjusted by changing the specified angle θ. For example, the sound wave W1 is controlled in such a way that the larger the specified angle θ is, the more the directivity is biased toward one side in the first direction d1.
[0072] Figure 6 This is an explanatory diagram of the directivity in the first direction d1 of the acoustic lens 1 according to the first embodiment. Figure 6 It is a directional characteristic diagram (polar pattern). Figure 6 (a) shows the directivity of the sound wave W1 in the first direction d1 when the sound wave W1 is emitted from the speaker 2 without using the acoustic lens 1 . Figure 6 (b) shows the directivity of the sound wave W1 in the first direction d1 when the sound wave W1 is emitted from the speaker 2 using the acoustic lens 1. Figure 6 In the figure, the solid line represents the directivity of the sound wave W1 with a frequency of 5kHz, the dotted line represents the directivity of the sound wave W1 with a frequency of 8kHz, the dotted line represents the directivity of the sound wave W1 with a frequency of 10kHz, and the single-point dashed line represents the directivity of the sound wave W1 with a frequency of 12kHz. Figure 6 The right side in is equivalent to the side in the first direction d1. Figure 6 The left direction in corresponds to the other direction in the first direction d1.
[0073] like Figure 6 As shown in (a) of FIG. 1 , when the sound wave W1 is emitted from the speaker 2 without using the acoustic lens 1, the sound wave W1 is radiated almost uniformly in front of the speaker 2 and has almost no directivity. Figure 6 As shown in (b), when the acoustic lens 1 is used to emit the sound wave W1 from the speaker 2, in front of the speaker 2, the directivity of one sound wave W1 in the first direction d1 becomes wider, and the directivity of the other sound wave W1 in the first direction d1 becomes narrower. In this way, by using the acoustic lens 1, the directivity of the sound wave W1 in the first direction d1 can be controlled.
[0074] Next, use Figure 5 The control of the directivity of the sound wave W1 in the second direction d2 by the second control mechanism (plural second partition plates 112) is described. Figure 5 As shown, the distance between the plurality of sound paths P1 formed by the plurality of second partition plates 112 becomes shorter as it is farther from the center in the second direction d2. Then, the sound wave W1 passes through each sound path P1 and is radiated to the outside (the atmosphere).
[0075] Here, if Figure 5 As shown, in the second control mechanism, the position of the ear of the user U1 sitting on the seat 3 and one side located in the second direction d2 ( Figure 5 The imaginary point p in the upper side of the image is changed by the length of each second partition plate 112, and the arrival time of the sound wave W1 is staggered, thereby controlling the directivity in the second direction d2.
[0076] Specifically, as shown by the dotted line, the sound wave W1 reaching the ear of the user U1 located at the center in the second direction d2 is hardly blocked by the second partition plates 112 from passing through the center side in the second direction d2. In contrast, as shown by the single-point dashed line, the sound wave W1 reaching the imaginary point p located at one side in the second direction d2 is blocked by the second partition plates 112 from passing through the one side in the second direction d2, and is blocked more significantly as it moves toward the center in the second direction.
[0077] Therefore, the sound wave W1 heading toward the imaginary point p located on one side of the second direction d2 has a larger difference in the distance of the sound wave W1 radiated from each sound path P1 separated by each second partition plate 112 of the acoustic lens 1. Therefore, the difference in arrival time from the time the sound wave W1 is radiated to the time it reaches the imaginary point p becomes larger, and the effect of cancellation of the sound wave W1 caused by the difference in arrival time becomes larger.
[0078] In contrast, the sound wave W1 directed toward the ear of the user U1 located in the center on the second direction d2 has less cancellation of the sound wave W1 caused by the difference in arrival time from the time the sound wave W1 is emitted to the time it reaches the ear of the user U1, because the difference in the passage distances of the sound wave W1 emitted from each sound channel P1 separated by the second partition plates 112 of the acoustic lens 1 is small.
[0079] Therefore, the sound pressure level of the sound wave W1 reaching the ear of the user U1 is relatively higher than the sound pressure level of the sound wave W1 reaching the virtual point p, and thus has directivity biased toward the center in the second direction d2.
[0080] Figure 7 1 is an explanatory diagram of the directivity in the second direction d2 of the acoustic lens 1 according to the first embodiment. Figure 7 It is a directional characteristic diagram (polar pattern). Figure 7 (a) shows the directivity of the sound wave W1 in the second direction d2 when the sound wave W1 is emitted from the speaker 2 without using the acoustic lens 1 . Figure 7 (b) shows the directivity of the sound wave W1 in the second direction d2 when the sound wave W1 is emitted from the speaker 2 using the acoustic lens 1. Figure 7 In FIG. 1 , the solid line represents the directivity of the sound wave W1 with a frequency of 5 kHz, the dotted line represents the directivity of the sound wave W1 with a frequency of 8 kHz, and the dotted line represents the directivity of the sound wave W1 with a frequency of 10 kHz. Figure 7 The right side in is equivalent to the side in the second direction d2, Figure 7 The left side in the figure corresponds to the other side in the second direction d2.
[0081] like Figure 7 As shown in (a) of FIG. 1 , when the sound wave W1 is emitted from the speaker 2 without using the acoustic lens 1, the sound wave W1 is radiated almost uniformly in front of the speaker 2 and has almost no directivity. Figure 7 As shown in (b), when the sound wave W1 is emitted from the speaker 2 using the acoustic lens 1, the directivity of the sound wave W1 is narrowed in one direction and the other direction in the second direction d2 in front of the speaker 2. In this way, by using the acoustic lens 1, the directivity of the sound wave W1 in the second direction d2 can be controlled.
[0082] [2. Advantages]
[0083] The advantages of the acoustic lens 1 and the speaker system 100 of Embodiment 1 are described below. As described above, in the acoustic lens 1 of Embodiment 1, the directivity of the sound wave W1 in the first direction d1 can be controlled by the first control mechanism (plural first partitions 111), and the directivity of the sound wave W1 in the second direction d2 can be controlled by the second control mechanism (plural second partitions 112). Therefore, the acoustic lens 1 of Embodiment 1 has the advantage of being easy to control the directivity of the sound wave W1 in each of the two mutually intersecting directions (the first direction d1 and the second direction d2).
[0084] In Embodiment 1, the first direction d1 is set as the horizontal direction, and the second direction d2 is set as the vertical direction, and the acoustic lens 1 can control the directivity of the sound wave W1 in the horizontal direction and the vertical direction. Therefore, the acoustic lens 1 of Embodiment 1 and the speaker system 100 using the acoustic lens 1 can eliminate the problems of the speaker system 200 of the comparative example.
[0085] For example, Figure 2 As shown, the speaker system 100 is respectively arranged near the left ear and the right ear of the user U1 sitting in the seat 3, and the acoustic lens 1 is arranged in a manner that the sound wave W1 has a directivity that is biased toward the user U1 in the horizontal direction (first direction d1). In this case, the sound wave W1 emitted by the speaker 2 is radiated in a manner that is biased toward the user U1 in the horizontal direction through the acoustic lens 1, so that the sound is difficult to leak to the user U2 sitting in the seat 3A adjacent to the seat 3. In addition, in this case, the sound wave W1 emitted by the speaker 2 is radiated in a manner that is biased toward the front of the user U1 without being diffused in the vertical direction through the acoustic lens 1, so that the sound wave W1 is difficult to go around the back of the seat 3, and the sound is difficult to leak to the user sitting in the seat located behind the seat 3.
[0086] Similarly, the speaker system 100 is respectively arranged near the left ear and the right ear of the user U2 sitting in the seat 3A adjacent to the seat 3, and the acoustic lens 1 is arranged in a manner that the sound wave W1 has a directivity that is biased toward the user U2 in the horizontal direction (first direction d1). In this case, the sound wave W1 emitted by the speaker 2 is radiated in a manner that is biased toward the user U2 in the horizontal direction through the acoustic lens 1, so that the sound is difficult to leak to the user U1 sitting in the seat 3. In addition, in this case, the sound wave W1 emitted by the speaker 2 is radiated in a manner that is biased toward the front of the user U2 without being diffused in the vertical direction through the acoustic lens 1, so that the sound wave W1 is difficult to go around the back of the seat 3A, and the sound is difficult to leak to the user sitting in the seat located behind the seat 3A.
[0087] As described above, the acoustic lens 1 according to the first embodiment and the speaker system 100 using the acoustic lens 1 have the advantage of being able to easily suppress sound leakage to persons other than the target user U1 (or user U2 ).
[0088] (Implementation Method 2)
[0089] [1. Composition]
[0090] Hereinafter, an acoustic lens 1A according to a second embodiment and a speaker system 100A including the acoustic lens 1A will be described. Figure 8 1 is a schematic diagram showing a configuration of a speaker system 100A including an acoustic lens 1A according to a second embodiment. Figure 8 (a) shows a stereoscopic view of the acoustic lens 1A. Figure 8 (b) shows a perspective view of the speaker system 100A. Fig. 9 This is a partially cutaway perspective view of the speaker system 100A according to the second embodiment. Fig.10 1 is a top view of a speaker system 100A according to Embodiment 2. In the following description, description of the same configuration as Embodiment 1 is appropriately omitted. Figure 8 and Fig.10 In the figures, the illustration of the sound wave W1 is omitted.
[0091] like Figure 8 As shown in (b), the speaker system 100A includes an acoustic lens 1A and a speaker 2 (see Fig. 9 ) and housing 4. The speaker system 100A is the same as the speaker system 100 of Embodiment 1, and is a system for allowing the target user U1 to listen to the sound wave W1 emitted from the speaker 2 and radiated through the acoustic lens 1A. The structure of the speaker 2 and the configuration of the speaker system 100A are the same as those of Embodiment 1, and therefore the description thereof is omitted here.
[0092] The housing 4 is formed in a flat rectangular parallelepiped shape and holds the acoustic lens 1A and the speaker 2. Specifically, the speaker 2 is accommodated inside the housing 4. The housing 4 is provided with an opening, and the acoustic lens 1A is held in the housing 4 so that the acoustic lens 1A is exposed to the outside through the opening.
[0093] like Figure 8 As shown in (a), the acoustic lens 1A includes an opening 10, a plurality of partition plates 11, and a plurality of partition plates 12. In Embodiment 2, the plurality of partition plates 11 are a plurality of third partition plates 113 arranged in the first direction d1. The plurality of partition plates 12 are made of the same material as the partition plates 11 and are arranged in the second direction d2. In addition, the partition plates 12 hardly contribute to the control of the directivity of the sound wave W1, so the description thereof is omitted here.
[0094] In implementation mode 2, if Fig. 9 As shown, the first control mechanism is formed by a plurality of third partition plates 113 having different lengths l3 in the traveling direction of the sound wave W1 and being inclined at a first angle θ1 relative to the traveling direction of the sound wave W1. The first angle θ1 is an acute angle, for example, 45±1 to 5 degrees. In addition, the first angle θ1 can be an acute angle, and as an example, it can also be 30±1 to 5 degrees, or 60±1 to 5 degrees, etc.
[0095] Here, the plurality of third partition plates 113 are arranged along the first direction d1 in accordance with the length l3 of the acoustic wave W1 in the traveling direction. Fig. 9 ) towards the other side ( Fig. 9 In other words, the third partition plates 113 are arranged so that the length l3 of the third partition plate 113 in the traveling direction of the sound wave W1 becomes longer the closer it is to the side where the sound wave W1 is desired to have directivity in the first direction d1.
[0096] In addition, in Embodiment 2, Fig.10 As shown, the second control mechanism is formed by a plurality of third partition plates 113 which are respectively inclined at second angles θ2 different from each other with respect to the second direction d2 and are arranged in a direction from the traveling direction of the sound wave W1 (with respect to the traveling direction of the sound wave W1). Fig.10 The plurality of third partition plates 113 are arranged in a line-symmetrical manner across the center of the second direction d2 when viewed from the direction perpendicular to the paper surface in the second direction d1. Fig.10 ) towards the other side ( Fig.10 The right side of the figure is configured to make the value smaller.
[0097] The second angle θ2 is, for example, in the range of 0±1 to 5 degrees or more and 20±1 to 5 degrees or less. The second angle θ2 may be an acute angle (including 0 degrees), and may be, for example, in the range of 30±1 to 5 degrees or less, or in the range of 60±1 to 5 degrees or less.
[0098] [2. Advantages]
[0099] The advantages of the acoustic lens 1A and the speaker system 100A of Embodiment 2 are described below. As described above, in the acoustic lens 1A of Embodiment 2, the directivity of the sound wave W1 in the first direction d1 can be controlled by the first control mechanism (plural third partitions 113), and the directivity of the sound wave W1 in the second direction d2 can be controlled by the second control mechanism (plural third partitions 113). Therefore, the acoustic lens 1A of Embodiment 2 has the advantage of being easy to control the directivity of the sound wave W1 in each of the two mutually intersecting directions (the first direction d1 and the second direction d2), similarly to the acoustic lens 1 of Embodiment 1.
[0100] In Embodiment 2, similarly to Embodiment 1, the first direction d1 is set to the horizontal direction, and the second direction d2 is set to the vertical direction, and the acoustic lens 1A can control the directivity of the sound wave W1 in the horizontal direction and the vertical direction. Therefore, the acoustic lens 1A of Embodiment 2 and the speaker system 100A using the acoustic lens 1A can solve the problem of the speaker system 200 of the comparative example similarly to Embodiment 1.
[0101] (Other embodiments)
[0102] As mentioned above, although Embodiment 1 and Embodiment 2 were described, this invention is not limited to the said Embodiment 1 and Embodiment 2.
[0103] In Embodiment 1, all of the plurality of first partition plates 111 are inclined relative to the traveling direction of the sound wave W1 , but the present invention is not limited thereto. For example, only a portion of the plurality of first partition plates 111 may be inclined.
[0104] In addition, the acoustic lens 1 of the first embodiment may also be Fig.11 The composition shown. Fig.11 1 is a schematic diagram showing the structure of an acoustic lens 1 according to a modified example of the first embodiment. Fig.11 As shown in (a), the plurality of first partition plates 111 and the plurality of second partition plates 112 may be configured so as not to be inclined relative to the traveling direction of the sound wave W1. Fig.11 As shown in (b), the plurality of first partition plates 111 may have the same length l1 along the traveling direction of the sound wave W1 and a predetermined angle θ along one side of the first direction d1 ( Fig.11 (b) inward) toward the other side ( Fig.11 It is configured under the condition that the angle becomes smaller (the near front side in (b)).
[0105] In addition, for example, Fig.11 As shown in (c), the plurality of second partition plates 112 may also be arranged in accordance with the length l2 in the traveling direction of the sound wave W1 along the direction from one side of the second direction d2 ( Fig.11 (c) to the left) towards the other side ( Fig.11 In addition, the plurality of second partition plates 112 may be respectively inclined at a predetermined angle θ' relative to the traveling direction of the sound wave W1. The predetermined angle θ' is an acute angle, for example, 45±1 to 5 degrees. In addition, the predetermined angle θ' only needs to be an acute angle, and as an example, it may be 30±1 to 5 degrees, or 60±1 to 5 degrees, etc.
[0106] In addition, various modifications that can be conceived by those skilled in the art to the embodiments, or embodiments achieved by arbitrarily combining the components and functions described in the embodiments without departing from the gist of the present disclosure are also included in the present disclosure.
[0107] Industrial availability
[0108] The present disclosure is useful as a means for controlling the directivity of sound waves emitted from a speaker.
[0109] Description of Reference Numerals
[0110] 1. 1A acoustic lens
[0111] 10 Opening
[0112] 11 Divider
[0113] 111 First partition
[0114] 112 Second partition
[0115] 113 Third partition
[0116] 12 Dividing board
[0117] 2 Speakers
[0118] 3. Seat 3A
[0119] 31, 31A headrest
[0120] 100, 100A speaker system
[0121] 200 Comparative Example Speaker System
[0122] d1 first direction
[0123] d2 Second direction
[0124] l1, l2, l3 length
[0125] p Virtual point
[0126] P1 channel
[0127] U1, U2 users
[0128] W1 Sonic
[0129] Angles specified by θ and θ'
[0130] θ1 First angle
[0131] θ2 Second angle
Claims
1. An acoustic lens comprising: an opening to which sound waves emitted from the speaker are input; and A plurality of partition plates constitute a plurality of sound channels through which the sound waves input to the opening pass, The plurality of partition plates have: a first control mechanism for controlling the directivity in a first direction of the sound waves output to the outside through the plurality of sound channels; and The second control means controls the directivity of the sound waves output to the outside through the plurality of channels in a second direction intersecting the first direction.
2. The acoustic lens according to claim 1, The first control mechanism is composed of a plurality of first partition plates arranged along the first direction and having different lengths in the traveling direction of the sound wave, among the plurality of partition plates. The second control mechanism is composed of a plurality of second partition plates, which are arranged in the second direction and have different lengths in the direction in which the sound waves travel, among the plurality of partition plates.
3. The acoustic lens according to claim 2, The lengths of the plurality of first partition plates in the direction in which the sound waves travel are shortened from one direction toward the other direction in the first direction.
4. The acoustic lens according to claim 2 or 3, The lengths of the plurality of second partition plates in the traveling direction of the sound wave become shorter as they are farther away from the center in the second direction.
5. The acoustic lens according to claim 2 or 3, At least one of the plurality of first partition plates and the plurality of second partition plates is inclined at a predetermined angle with respect to a propagation direction of the sound wave.
6. The acoustic lens according to claim 5, The predetermined angle is different among the partition plates.
7. The acoustic lens according to claim 2 or 3, The first direction and the second direction are orthogonal to each other.
8. The acoustic lens according to claim 1, The plurality of partition plates are a plurality of third partition plates arranged along the first direction, The first control mechanism is formed by the plurality of third partition plates having different lengths in the traveling direction of the sound wave and being inclined at a first angle relative to the traveling direction of the sound wave. The second control mechanism is configured by the plurality of third partition plates being inclined at second angles different from each other with respect to the second direction and being arranged line-symmetrically with respect to the center in the second direction when viewed from the traveling direction of the sound wave.
9. A speaker system comprising: The acoustic lens according to any one of claims 1 to 3 and 8; and The speaker emits the sound wave toward the opening of the acoustic lens.