Sound apparatus

Abstract

To provide a sound apparatus in which sound quality is enhanced.SOLUTION: A sound apparatus 1 includes: a vibration member 90 having a plate shape; and a first vibration device 11, a plurality of second vibration devices 21-24, and a third vibration device 31 which each have a plate shape including a first main surface and a second main surface opposite to each other and vibrate based on a driving signal input thereto. The first main surface of the first vibration device is connected to the vibration member. A portion of the second main surface of the first vibration device and a portion of the first main surface of the third vibration device are connected to each other by an elastic member 51 so that the first main surface of the third vibration device is spaced apart from and opposite to the second main surface of the first vibration device by a predetermined distance. A portion of each of the plurality of second vibration devices is connected to a portion of the third vibration device by an elastic member 62 so that the plurality of second vibration devices extend radially from the third vibration device in plan view. A portion of the first main surface of each of the plurality of second vibration devices is connected to a portion of the vibration member by elastic members 41-44. A driving signal input to the first vibration device has a phase different from a phase of a driving signal input to the third vibration device.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] This specification relates to an audio device. [Background technology]

[0002] An audio device has a vibration system that converts an input electrical signal into physical vibration. Piezoelectric speakers, which are made of piezoelectric elements such as ferroelectric ceramics, have the advantages of being lightweight and consuming low power, and are therefore used for a variety of purposes. Summary of the Invention [Problem to be solved by the invention]

[0003] The piezoelectric elements used in piezoelectric speakers have a limited vibration amplitude (or displacement amplitude), and therefore may not provide sufficient sound quality.

[0004] The present specification has been made in consideration of the above-mentioned problems, and the inventor of the present specification has conducted several experiments in order to realize an audio device capable of improving sound quality. Through several experiments, the inventor has invented a new audio device capable of improving sound quality. The present specification aims to improve the sound quality of an audio device. [Means for solving the problem]

[0005] According to one or more embodiments of the present specification, there is provided an acoustic device comprising: a vibration member having a flat plate shape; a first vibration element, a plurality of second vibration elements, and a third vibration element, each of which has a flat plate shape including first and second main surfaces facing each other and is configured to vibrate in response to an input drive signal, wherein the first main surface of the first vibration element is connected to the vibration member, a portion of the second main surface of the first vibration element and a portion of the first main surface of the third vibration element are connected via an elastic member so that the first main surface of the third vibration element faces the second main surface of the first vibration element at a predetermined distance, a portion of each of the plurality of second vibration elements is connected to a portion of the third vibration element and a portion of the first main surface of each of the plurality of second vibration elements is connected to a portion of the vibration member via an elastic member so that the plurality of second vibration elements extend radially from the third vibration element in a planar view, and a drive signal input to the first vibration element has a phase opposite to that of a drive signal input to the third vibration elements. Effect of the Invention

[0006] According to the present specification, the sound quality of an audio device can be improved. According to the present specification, the sound pressure characteristics and / or acoustic characteristics in the bass range of an audio device can be improved.

[0007] Both the foregoing description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the disclosure as set forth in the appended claims.

[0008] The accompanying drawings, which are included to provide a further understanding of the specification and are incorporated in and constitute a part of the specification, illustrate aspects and implementations of the specification and, together with the description, may serve to explain the principles of the specification. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram showing the configuration of an audio device and a host system according to a first embodiment of the present specification. [Diagram 2] 1 is a perspective view showing a configuration of an audio device according to a first embodiment of the present specification. [Diagram 3] 1 is a plan view showing a configuration of an acoustic device according to a first embodiment of the present specification. [Figure 4] 1 is a cross-sectional view showing a configuration of an acoustic device according to a first embodiment of the present specification. [Diagram 5] 1 is a cross-sectional view showing a configuration of an acoustic device according to a first embodiment of the present specification. [Figure 6] 1 is a cross-sectional view showing in more detail the structure of an acoustic device according to a first embodiment of the present specification. [Figure 7] 4 is a graph showing acoustic characteristics of the audio device according to the first embodiment of the present specification. [Figure 8] FIG. 11 is a perspective view showing a configuration of an audio device according to a second embodiment of the present specification. [Figure 9] FIG. 11 is a plan view showing the configuration of an acoustic device according to a second embodiment of the present specification. [Figure 10] FIG. 11 is a cross-sectional view showing the configuration of an acoustic device according to a second embodiment of the present specification. [Figure 11] FIG. 11 is a cross-sectional view showing in more detail the configuration of an acoustic device according to a second embodiment of the present specification. [Figure 12] FIG. 11 is a plan view showing the structure of a vibration element according to a third embodiment. [Figure 13] 13 is a cross-sectional view taken along line DD' of FIG. 12 according to the third embodiment. [Figure 14] FIG. 13 is a perspective view showing a vibration layer of a vibration element according to a fourth embodiment. [Figure 15] FIG. 13 is a perspective view showing a vibration layer of a vibration element according to a fifth embodiment. [Figure 16] FIG. 13 is a configuration diagram of a display device according to a sixth embodiment of the present specification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Reference will now be made in detail to the embodiments of the present specification, examples of which may be illustrated in the accompanying drawings. In the following description, if a detailed description of a well-known function or configuration unnecessarily obscures the gist of the present specification, the detailed description may be omitted for the sake of brevity. The progression of steps and / or operations described is exemplary, but the order of steps and / or operations is not limited to that described herein and may be modified, except that steps and / or operations necessarily occur in a particular order.

[0011] Unless otherwise specified, the same reference numerals may generally refer to similar components even if they are illustrated in different drawings. In one or more embodiments, the same components (or components having the same name) in different drawings may have the same or substantially the same functions and characteristics, unless otherwise specified. The names of the respective components used in the following description are selected for convenience and may differ from the actual products.

[0012] The advantages and features of the present specification and methods for achieving them will become apparent from various examples described below in detail with reference to the accompanying drawings. However, the present specification is not limited to the embodiment disclosed below, and may be realized in various different forms, and the embodiment etc. of the present specification are provided only to complete the disclosure of the present specification and to fully inform those skilled in the art of the technical idea of ​​the present specification of the scope of the technical idea.

[0013] The shapes, sizes, areas, ratios, angles, numbers, etc. disclosed in the drawings for explaining an embodiment of this specification are merely illustrative, and the present specification is not limited to the details shown in the drawings.

[0014] When the terms "comprise", "have", "consist", "comprise", "formed", etc. are used in this specification, other parts can be added unless "only" or "only" is used. The terms used in this specification are used only to describe a particular embodiment and are not intended to limit the scope of the specification. The terms used in this specification are used only to describe an exemplary embodiment and are not intended to limit the scope of the specification. Terms expressing elements in the singular include the plural unless otherwise expressly stated. An "embodiment" may be an illustrative example. Any implementation described in the "embodiment" or "example" described in this specification should not necessarily be construed as preferred or advantageous over other implementations.

[0015] In one or more embodiments, components, features, or corresponding information (e.g., levels, ranges, dimensions, sizes, etc.) may be interpreted as including an error or tolerance range even if an explicit description of these error or tolerance ranges is not provided. The error or tolerance range may be caused by various factors (e.g., process factors, internal or external impacts, noise, etc.).

[0016] In the case of a description of a location relationship, when a location relationship is described between two parts using words such as "on or over," "on top," "under or below," "at the bottom," "near," "adjacent to," "beside," or "next to," one or more other parts may be located between the two parts, unless "just," "immediately(ly)," "close(ly)," or "direct(ly)" is used. For example, when structures are described as being located "above or over," "on top," "under or below," "on bottom," "near," "adjacent to," "beside," or "next to," this description must be interpreted to include cases where the structures touch each other and have a third structure disposed between them. For example, when structures are described as being located "above or over," "on top," "under or below," "on bottom," "near," "adjacent to," "beside," or "next to," this description must be interpreted to include cases where the structures touch each other and have a third structure disposed between them. Additionally, "front", "back", "back", "left", "right", "top", "bottom", "downward", "upward", "top", "bottom", "column", "row", "vertical", "horizontal", etc. refer to any frame of reference.

[0017] In the case of descriptions of temporal relationships, when the temporal sequence is described using "after," "subsequent," "next," "before, preceding, or prior to," etc., consecutive or non-consecutive cases can also be included, since "just," "immediately," or "directly" are not used.

[0018] Although the terms "first", "second", etc. are used to describe various components, these components are not limited to these terms. These terms are used only to distinguish one component from another component. Thus, a first component referred to below may also be a second component within the technical spirit of this specification. Furthermore, the first element, the second element, etc. may be named arbitrarily according to the convenience of a person skilled in the art without departing from the scope of this specification. Terms such as "first", "second", etc. may be used to distinguish components from each other, but the function or structure of the component is not limited by the ordinal number before the component or the name of the component.

[0019] In describing components of this specification, terms such as first, second, A, B, (a), (b), etc. may be used. Such terms are used to distinguish the components from other components, and are not used to define the nature, basis, order, or number of the components.

[0020] When a component or layer is described as being "connected," "bonded," or "connected" to another component, it should be understood that the component may be directly connected or connected to the other components, but that other components or layers may be "disposed" or "interpodated" between each component that may be indirectly connected or connected unless specifically and explicitly stated.

[0021] When a component or layer is described as being in "contact with" or "overlapping" another component or layer, it should be understood that the component may be in direct contact with or overlaid on the other component or layer, but one or more other components or layers may be "disposed" or "interpodded" between each component or layer that may be in indirect contact or overlaid unless otherwise expressly described. For example, for purposes of this specification, terms such as "overlap" and "overlapping" should be understood as "overlapping, electrically and / or physically connected" by, for example, surface-to-surface connection, and "overlapping, electrically and / or physically connected" by, for example, surface-to-surface connection.

[0022] Terms such as "line" or "direction" should not be construed solely in terms of a geometric relationship in which the respective lines or directions are aligned or perpendicular to one another, but can refer to lines or directions that have a broader orientation within which the components of this specification can functionally operate.

[0023] The term "at least one" should be understood to include all possible combinations of one or more of the associated items. For example, the meaning of "at least one of the first, second, and third items" may include only any combination of the first, second, and third items, and not just combinations of items presented from two or more of the first, second, or third items.

[0024] The phrase "first component", "second component" and / or "third component" should be understood as one of the first, second and third components or any or all combinations of the first, second and third components. For example, A, B and / or C can be considered as A only, B only, C only, any or some combination of A, B and C, or all of A, B and C. Furthermore, the phrase "component A / component B" should be understood as component A and / or component B.

[0025] In one or more embodiments, the terms "between" and "in" may be used interchangeably for convenience only, unless otherwise specified. For example, the phrase "between multiple components" may also be understood as "among multiple components." In other embodiments, the phrase "among multiple components" may also be understood as "between multiple components." In one or more embodiments, the number of components may be two. In one or more embodiments, the number of components may be more than two.

[0026] In one or more embodiments, the term "different from each other" may be understood to mean that any component is different from the other component.

[0027] In one or more embodiments, the terms "one or more of" and "one or more of" may be used interchangeably for convenience only, unless otherwise specified. For example, the term "one or more of" can also be understood as "one or more of." For example, the term "one or more of" can also be understood as "one or more of."

[0028] The features of one or more embodiments of the present specification may be combined or combined with each other in part or in whole, and may be technically linked and operated in various ways, and each embodiment may be implemented independently of each other, or may be implemented together in a linked relationship. In one or more embodiments, the components of each device according to various embodiments of the present specification may be operably coupled or configured.

[0029] The terms used in this specification (including technical and scientific terms) may have the same meaning as that understood by a person having ordinary knowledge in the technical field to which this specification belongs. Furthermore, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant technology, and should not be interpreted as idealized or overly formal unless otherwise specified.

[0030] Hereinafter, the embodiments according to the present specification will be described in detail with reference to the drawings. Elements having common functions throughout the drawings are given the same reference numerals, and duplicated descriptions may be omitted or simplified. Furthermore, for convenience of explanation, the scales, dimensions, sizes, and thicknesses of the components shown in the drawings may have different scales, dimensions, sizes, and thicknesses from the actual scales, dimensions, sizes, and thicknesses, and therefore are not limited to the scales, dimensions, sizes, and thicknesses shown in the drawings.

[0031] [First embodiment] Fig. 1 is a block diagram showing the configuration of an audio device 1 according to this embodiment. With reference to Fig. 1, a drive signal (or an audio signal) input to the audio device 1 will be described. The audio device 1 may be used independently as a speaker, or may be built into an advertising billboard, a poster, a guide board, a display device, etc. The use of the audio device 1 of this embodiment is not particularly limited.

[0032] The acoustic device 1 may have a first vibration element 11, a plurality of second vibration elements 21-24, and a third vibration element 31. The first vibration element 11, the second vibration elements 21-24, and the third vibration element 31 may be piezoelectric elements that are displaced by an inverse piezoelectric effect when a voltage based on an input drive signal is applied. The first vibration element 11, the second vibration elements 21-24, and the third vibration element 31 may be elements that are displaced by bending in response to a voltage, such as a bimorph, a unimorph, or a multimorph. Since the input drive signal is usually an AC voltage, the first vibration element 11, the second vibration elements 21-24, and the third vibration element 31 can vibrate in response to the input drive signal to generate sound. For example, the first vibration element 11, the second vibration elements 21-24, and the third vibration element 31 may be a vibration generating element, an acoustic generating element, a piezoelectric element, a vibration generator, an acoustic generator, a piezoelectric speaker, or a sound generating element, but the embodiments of this specification are not limited thereto.

[0033] The host system 7 is a device or a system including multiple devices that controls the audio device 1 by supplying a drive signal. However, the host system 7 may also supply other signals, such as image signals (e.g., RGB data or RGBW data), timing signals (e.g., vertical synchronization signal, horizontal synchronization signal, data enable signal, etc.), depending on the application of the audio device 1. The host system 7 may be, for example, a sound source playback device, a public address device, a radio broadcast playback system, a television system, a set-top box, a navigation system, an optical disc player, a computer, a home theater system, a video telephone system, etc. The audio device 1 and the host system 7 may be an integrated device or separate devices.

[0034] The host system 7 may include an input unit 701, a D / A (Digital / Analog) converter 711, a PWM (Pulse Width Modulation) circuit 712, transistors 721 and 722, a coil 723, and a capacitor 724. The input unit 701 inputs a digital signal for controlling the first vibration element 11, the second vibration elements 21 to 24, and the third vibration element 31. The D / A converter 711 can convert the digital signal input from the input unit 701 into an analog signal. The PWM circuit 712 pulse-width modulates the analog signal input from the D / A converter 711 and outputs a pulse signal. The PNP-type transistor 721 and the NPN-type transistor 722 can form a push-pull circuit. For example, the collector terminals of the transistors 721 and 722 may be connected to each other, and the base terminals of the transistors 721 and 722 may be connected to each other. A positive voltage +Vdd may be applied to the emitter terminal of the transistor 721, and a negative voltage -Vdd may be applied to the emitter terminal of the transistor 722. A pulse signal is applied to the base terminals of the transistors 721 and 722 from the PWM circuit 712, and the transistors 721 and 722 may be driven on or off complementarily in response to the pulse signal. For example, when a positive pulse signal is applied to the base terminals of the transistors 721 and 722, the transistor 721 is turned on and the transistor 722 is turned off. Therefore, the voltages of the collector terminals of the transistors 721 and 722 are voltage +Vdd. On the other hand, when a negative pulse signal is applied to the base terminals of the transistors 721 and 722, the transistor 721 is turned off and the transistor 722 is turned on. Therefore, the voltages of the collector terminals of the transistors 721 and 722 are voltage -Vdd. Also, when the potential of the pulse signal becomes the ground potential, both the transistors 721 and 722 are turned off. The coil 723 and the capacitor 724 function as a low-pass filter to smooth the pulse signals at the collector terminals of the transistors 721 and 722 and output them to the first vibration element 11, the second vibration elements 21 to 24 and the third vibration element 31 as drive signals (or audio signals).

[0035] FIG. 2 is a perspective view showing the configuration of an acoustic device according to this embodiment. FIG. 3 is a plan view showing the configuration of an acoustic device according to this embodiment. FIGS. 4 and 5 are cross-sectional views showing the configuration of an acoustic device according to this embodiment. FIG. 6 is a cross-sectional view showing the structure of a vibration element according to this embodiment in more detail. FIGS. 4 and 6 show cross-sectional views taken along line A-A' in FIG. 3 according to this embodiment. FIG. 5 shows a cross-sectional view taken along line B-B' in FIG. 3 according to this embodiment. The specific configuration of an acoustic device 1 according to this embodiment will be described with mutual reference to FIGS. 2 to 6.

[0036] As shown in FIG. 2, the acoustic device 1 may include a first vibration element 11, second vibration elements 21-24, and a third vibration element 31. The acoustic device 1 may further include elastic members 41-44, 51, and a vibration member 90. As shown in FIG. 2 and FIG. 3, the first vibration element 11 and the third vibration element 31 may have the same shape as each other in a plan view. The second vibration elements 21-24 may have the same shape and size as each other in a plan view. In a plan view, the second vibration elements 21-24 may have a different shape and size from the first vibration element 11 and the third vibration element 31. For example, the first vibration element 11 and the third vibration element 31 may have a rectangular or substantially square flat plate shape in a plan view. The second vibration elements 21-24 may have a rectangular flat plate shape including a short side and a long side in a plan view. 2 to 6 show coordinate axes in which the short side direction of the second vibration element 21 is the x-axis, the long side direction is the y-axis, and the direction perpendicular to the x-axis and y-axis is the z-axis. The direction parallel to the x-axis is called the first direction, and the direction parallel to the y-axis is called the second direction. In this embodiment, the first direction and the second direction form a right angle in a plan view. The first vibration element 11, the second vibration elements 21 to 24, and the third vibration element 31 can each have two main surfaces that face each other. Of the two main surfaces of the first vibration element 11, the surface on the negative side of the z-axis is called the first main surface 11a, and the surface on the positive side of the z-axis is called the second main surface 11b. Similarly, of the two main surfaces of each of the second vibration elements 21 to 24, the surface on the negative side of the z axis is referred to as the first main surface 21a, 22a, 23a, and 24a, respectively, and the surface on the positive side of the z axis is referred to as the second main surface 21b, 22b, 23b, and 24b, respectively. Similarly, of the two main surfaces of the third vibration element 31, the surface on the negative side of the z axis is referred to as the first main surface 31a, and the surface on the positive side of the z axis is referred to as the second main surface 31b.

[0037] The first vibration element 11 may be disposed on a main surface of the vibration member 90. For example, the entire surface of the first main surface 11a of the first vibration element 11 is in contact with the vibration member 90. For example, the first vibration element 11 and the vibration member 90 may be connected to each other via an adhesive member 61 (or an adhesive agent or an adhesive layer or a first adhesive member). Vibrations generated from the first vibration element 11 by an input drive signal (or an audio signal) may be transmitted directly (or via the adhesive member 61) to the vibration member 90. For example, the first vibration element 11 may be connected to the vibration member 90 by a full-surface adhesion method using an adhesive member.

[0038] The second vibration elements 21-24 may be disposed above the first vibration element 11. A portion of each of the second vibration elements 21-24 may overlap the first vibration element 11 and the third vibration element 31 in a planar view. The second vibration elements 21-24 do not directly contact the first vibration element 11. The second vibration elements 21-24 may be disposed rotationally symmetrically about an axis (z-axis) perpendicular to the first main surface 31a and the second main surface 31b of the third vibration element 31 in a planar view. Specifically, each of the four second vibration elements 21-24 may have a property of four-fold symmetry about the z-axis. For example, the second vibration element 22 may extend in a direction rotated 90 degrees clockwise from the longitudinal direction of the second vibration element 21 in a planar view. Similarly, in a plan view, the second vibration element 23 can extend in a direction rotated 90 degrees clockwise from the longitudinal direction of the second vibration element 22, and the second vibration element 24 can extend in a direction rotated 90 degrees clockwise from the longitudinal direction of the second vibration element 23. Also, in a plan view, the second vibration element 21 can extend in a direction rotated 90 degrees clockwise from the longitudinal direction of the second vibration element 24. The second vibration elements 21 to 24 can be arranged so as not to contact each other. A part of the first main surface 21a of the second vibration element 21 can be connected to a part of the main surface of the vibration member 90 via the elastic member 41 (or the first elastic member). Similarly, a part (or a first end) of the first main surfaces 22a, 23a, 24a of the second vibration elements 22, 23, 24 can be connected to a part of the main surface of the vibration member 90 via the elastic members 42 to 44 (or the first elastic member). For example, each end (or short side) of the second vibration elements 21-24 adjacent to the center of the first vibration element 11 may be spaced apart in different directions from the center of the first vibration element 11 within a range overlapping with the first vibration element 11. The heights of the elastic members 41-44 in the z-axis direction in a cross-sectional view may be the same. Therefore, the second vibration elements 21-24 may be disposed at the same position (or height) in the z-axis direction. Therefore, the second vibration elements 21-24 do not overlap with each other in a plan view. The vibrations generated from the second vibration elements 21-24 by the input drive signal (or audio signal) may be transmitted to the vibration member 90 via the elastic members 41-44, respectively.

[0039] The elastic members 41-44 according to this embodiment may be provided at the end (or the second end) opposite to the part of each of the second vibration elements 21-24 connected to the third vibration element 31 in a cross-sectional view. However, the elastic members 41-44 according to this embodiment do not necessarily need to be disposed at the positions shown in this embodiment. For example, the elastic members 41-44 may be disposed in a portion (for example, a center portion of each of the first principal surfaces 21a-24a) that does not overlap with the part of each of the second principal surfaces 21b-24b of the second vibration elements 21-24 connected to the third vibration element 31 in a plan view.

[0040] The third vibration element 31 may be disposed above the first vibration element 11. Specifically, the third vibration element 31 is disposed so that the first main surface 31a of the third vibration element 31 faces the second main surface 11b of the first vibration element 11 at a predetermined distance. For example, the third vibration element 31 does not directly contact the first vibration element 11. The third vibration element 31 may be connected to a corner of the rectangular second main surface 11b of the first vibration element 11 via four elastic members 51 (or second elastic members) disposed at a corner (or a first portion) of the rectangular first main surface 31a. The height of the four elastic members 51 in the z-axis direction may correspond to a predetermined distance between the first main surface 31a of the third vibration element 31 and the second main surface 11b of the first vibration element 11. The shape of the third vibration element 31 may be the same as that of the first vibration element 11. For example, the four elastic members 51 may be four second elastic members, four connecting members, or four coupling members.

[0041] A part (or a second part) of the first main surface 31a of the third vibration element 31 may be connected to a part of the second main surfaces 21b, 22b, 23b, 24b of each of the second vibration elements 21 to 24 via an adhesive member 62 (or an adhesive agent, an adhesive layer, or a second adhesive member). Each of the second vibration elements 21 to 24 may extend radially from the third vibration element 31 in a planar view. For example, the angle between each of the second vibration elements 21 to 24 may be 90 degrees. Specifically, the second vibration elements 21 and 22 may be arranged such that the longitudinal direction is parallel to the second direction (y-axis direction). The second vibration element 21 and the second vibration element 22 may be arranged such that the short sides of each of the second vibration elements 21 and 22 face each other in a planar view with a predetermined space between the first vibration element and the third vibration element therebetween. The second vibration elements 23 and 24 may be arranged such that the longitudinal direction is parallel to the first direction (x-axis direction). The second vibration element 23 and the second vibration element 24 may be arranged such that their short sides in a plan view face each other with a predetermined space between the first vibration element and the third vibration element therebetween. Vibrations generated from the third vibration element 31 by an input drive signal (or an audio signal) may be transmitted to the vibration member 90 via the elastic member 51, the first vibration element 11, the second vibration elements 21-24, and the elastic members 41-44.

[0042] As shown in FIG. 2 to FIG. 5, among the second main surfaces 21b, 22b, 23b, and 24b of the second vibration elements 21 to 24, the portions not connected to the third vibration element 31 do not overlap with the third vibration element 31 in a planar view. In addition, in this embodiment, the first vibration element 11 and the third vibration element 31 have the same shape, and the entire surface of the second main surface 11b of the first vibration element 11 is covered by the third vibration element 31 in a planar view. For example, the first vibration element 11 can overlap with the third vibration element 31 in a planar view. Therefore, among the second main surfaces 21b, 22b, 23b, and 24b of the second vibration elements 21 to 24, the portions connected to the third vibration element 31 can overlap with the first vibration element 11 in a planar view.

[0043] The elastic members 41 to 44 may be connected to the vibration elements 21 to 24 and the vibration member 90 via the adhesive members 63 and 64 (or adhesive or adhesive layer). The elastic member 51 may be connected to the first vibration element 11 and the third vibration element 31 via the adhesive members 65 and 66 (or adhesive or adhesive layer). For example, the elastic members 41 to 44 may be connected to the vibration member 90 via the adhesive member 63 (or the third adhesive member). For example, the elastic members 41 to 44 may be connected to the vibration elements 21 to 24 via the adhesive member 64 (or the fourth adhesive member). For example, the elastic member 51 may be connected to the vibration element 11 via the adhesive member 65 (or the fifth adhesive member). For example, the elastic member 51 may be connected to the third vibration element 31 via the adhesive member 66 (or the sixth adhesive member). The elastic members 41 to 44 and 51 may be made of a material such as resin. Polyurethane and polyethylene terephthalate (PET) may be used as resins constituting the elastic members 41-44, 51, but the embodiment of the present specification is not limited thereto. At least a part of the elastic members 41-44, 51 may have a hexahedral shape, but the embodiment of the present specification is not limited thereto. For example, the elastic members 41-44, 51 may be rectangular in plan view and cross-sectional view. At least a part of the elastic members 41-44, 51 may have a cylindrical shape or an elliptical cylindrical shape. For example, the elastic members 41-44, 51 may be circular or elliptical in plan view and rectangular in cross-sectional view. The elastic members 41-44 may be a transmission member or a vibration transmission member that transmits vibrations generated by the second vibration element 21 based on an input drive signal to the vibration member 90. The elastic member 51 may be a transmission member or a vibration transmission member that transmits vibrations generated by the third vibration element 31 based on an input drive signal to the vibration member 90 via the first vibration element 11.

[0044] The vibration member 90 may be a manual vibration member, a vibration plate, or a vibration substrate. The vibration member 90 may have a flat plate shape, but the embodiment of the present specification is not limited thereto. The vibration member 90 may be made of a material such as metal, resin, glass, hard paper, wood, rubber, plastic, fiber, cloth, paper, leather, or carbon, but the embodiment of the present specification is not limited thereto. Stainless steel may be used as a metal constituting the vibration member 90, but the embodiment of the present specification is not limited thereto. For example, the vibration member 90 may be styrene. In addition, the vibration member 90 may include a display panel having pixels configured to display an image, a screen panel on which an image is projected from a display device, a lighting panel, a light-emitting diode lighting panel, an organic light-emitting lighting panel, an inorganic light-emitting lighting panel, a signage panel, an interior material of a vehicle, a glass window of a vehicle, an exterior material of a vehicle, a seat interior material of a vehicle, a ceiling material of a vehicle, a ceiling material of a building, an interior material of a building, a glass window of a building, an interior material of an aircraft, a glass window of an aircraft, or a mirror, but the embodiment of the present specification is not limited thereto.

[0045] According to another embodiment of the present specification, one or more of the adhesive members 61 to 66 may include an elastic material capable of being compressed and restored while having adhesive properties. For example, the adhesive members 61 to 66 may include an adhesive material having elasticity or stretchability. For example, the adhesive members 61 to 66 may include an adhesive material having a low elastic modulus (or Young's modulus). For example, the adhesive members 61 to 66 may be configured by an adhesive resin, an adhesive, an adhesive tape, an adhesive pad, or the like, but the embodiment of the present specification is not limited thereto. For example, the adhesive tape may include a double-sided tape, a double-sided foam tape, or a double-sided sponge tape, or the like, having an adhesive layer. The adhesive pad may include an elastic pad such as a rubber pad or a silicone pad, having an adhesive layer, capable of being compressed and restored.

[0046] According to other embodiments of the present specification, the adhesive resin, adhesive, or adhesive layer of the adhesive members 61 to 66 may include an epoxy-based, acrylic-based, silicone-based, or urethane-based adhesive material. For example, the adhesive members 61 to 66 may include an acrylic-based adhesive material having relatively excellent adhesive strength and high hardness among acrylic and urethane so that the vibration of the vibration element is well transmitted to the vibration member 90, but the embodiment of the present specification is not limited thereto.

[0047] The adhesive resin, adhesive, or adhesive layer of the adhesive members 61 to 66 according to the embodiment of the present specification may be a photocurable adhesive material, but the embodiment of the present specification is not limited thereto. For example, the adhesive resin, adhesive, or adhesive layer may be a UV (ultraviolet) adhesive, but the embodiment of the present specification is not limited thereto.

[0048] An example of the structure of the acoustic device 1 will be described in more detail with reference to Fig. 6. Fig. 6 is an enlarged view of the first vibration element 11, the second vibration elements 21, 22, 23, and the third vibration element 31 in the same cross section as Fig. 4. Fig. 6 also shows a schematic circuit diagram of the connection relationship of the electrodes included in the first vibration element 11, the second vibration elements 21, 22, and the third vibration element 31 to explain a method of inputting a drive signal to the acoustic device 1.

[0049] The first vibration element 11 may include an electrode 111 (or a first electrode), a vibration layer 112 (or a piezoelectric layer), and an electrode 113 (or a second electrode). The electrode 111 and the electrode 113 are arranged to sandwich the vibration layer 112 in the thickness direction. A voltage V1 may be applied to the vibration layer 112 via the electrode 111 and the electrode 113. The voltage V1 may correspond to a drive signal (or an audio signal).

[0050] The first vibration element 11 may further include a protective layer 117 (or a first protective member). The protective layer 117 may protect and / or insulate the upper surface of the electrode 111. The first vibration element 11 may further include a second protective layer 118 (or a second protective member). The second protective layer 118 may be configured to protect and / or insulate the lower surface of the electrode 113. One or more of the protective layer 117 and the second protective layer 118 may be omitted. In this embodiment, the polarization direction of the vibration layer 112 is the positive direction of the z axis as shown in FIG. 6, but may be the negative direction. Note that wiring for applying a voltage to each electrode may be connected to the electrodes 111 and 113 by soldering or the like.

[0051] The first vibration element 11 may be coupled to the vibration member 90 by an adhesive member 61 (or a first adhesive member). The adhesive member 61 may be configured to couple the first vibration element 11 to the vibration member 90.

[0052] The second vibration element 23 may include an electrode 231 (or a first electrode), a vibration layer 232 (or a piezoelectric layer), and an electrode 233 (or a second electrode). The electrode 231 and the electrode 233 are arranged to sandwich the vibration layer 232 in the thickness direction. A voltage V2 may be applied to the vibration layer 232 via a signal line, the electrode 231, and the electrode 233. The voltage V2 corresponds to a drive signal (or an audio signal) and may have a phase opposite to that of the voltage V1 applied to the first vibration element 11. For example, the drive signal input to the second vibration element 23 may have a phase opposite to that of the drive signal input to the first vibration element 11.

[0053] The second vibration element 23 may further include a protective layer 237 (or a first protective member). The protective layer 237 may protect and / or insulate the upper surface of the electrode 231. The second vibration element 23 may further include a second protective layer 238 (or a second protective member). The second protective layer 238 may protect and / or insulate the lower surface of the electrode 233. One or more of the protective layer 237 and the second protective layer 238 may be optional.

[0054] The second vibration element 23 may be connected to the third vibration element 31 by an adhesive member 62. The adhesive member 62 may be configured to connect a part of the second vibration element 23 to the first main surface 31a of the third vibration element 31. Although the direction is set to be the positive direction of the z-axis as shown in Fig. 6, it may be the negative direction. Wiring for applying a voltage to each electrode may be connected to the electrodes 231, 233 by soldering or the like.

[0055] The second vibration elements 21, 22, and 24 have a similar configuration to the second vibration element 23. For example, the second vibration element 21 can include a first electrode, a vibration layer, a second electrode, a first protective member, and a second protective member. The first electrode and the second electrode can be arranged to sandwich the vibration layer in the thickness direction. A voltage V2 can be applied to the vibration layer via a signal line, the first electrode, and the second electrode. For example, the drive signal input to the second vibration elements 21, 22, and 24 can have a phase opposite to that of the drive signal input to the first vibration element 11. As shown in FIG. 6, a part of the second vibration element 21 can be connected to the first main surface 31a of the third vibration element 31 by an adhesive member 62. In addition, the second vibration element 22 can include a first electrode, a vibration layer, a second electrode, a first protective member, and a second protective member. The first electrode and the second electrode can be arranged to sandwich the vibration layer in the thickness direction. A voltage V2 may be applied to the vibration layer via the signal line, the first electrode, and the second electrode. As shown in FIG. 2 and FIG. 6, a part of the second vibration element 22 may be connected to the first main surface 31a of the third vibration element 31 by an adhesive member 62. The second vibration element 24 includes a first electrode, a vibration layer, a second electrode, a first protective member, and a second protective member. The first electrode and the second electrode may be arranged to sandwich the vibration layer in the thickness direction. A voltage V2 may be applied to the vibration layer via the signal line, the first electrode, and the second electrode. A part of the second vibration element 24 may be connected to the first main surface 31a of the third vibration element 31 by an adhesive member 62.

[0056] The third vibration element 31 may include an electrode 311 (or a first electrode), a vibration layer 312 (or a piezoelectric layer), an electrode 313 (or a second electrode), a protective layer 317 (or a first protective member), and a protective layer 318 (or a second protective member). The electrode 311 and the electrode 313 may be arranged to sandwich the vibration layer 312 in the thickness direction. A voltage V2 may be applied to the vibration layer 312 via the electrode 311 and the electrode 313. The voltage V2 may correspond to a drive signal (or an audio signal) commonly applied to the second vibration elements 21 to 24 and the third vibration element 31. For example, the drive signal input to the third vibration element 31 may have the same phase as the phase of the drive signal input to the second vibration elements 21 to 24, and may have a phase opposite to the phase of the drive signal input to the first vibration element 11. The protective layer 317 protects and / or insulates the upper surface of the electrode 311. The protective layer 318 can protect and / or insulate the upper surface of the electrode 313. One or more of the protective layers 317 and 318 can be omitted. In this embodiment, the poling direction of the vibration layer 112 is the positive direction of the z-axis as shown in FIG. 6, but it can be the negative direction. Wiring for applying a voltage to each electrode can be connected to the electrodes 311 and 313 by soldering or the like.

[0057] The voltages applied to the first vibration element 11, the second vibration elements 21-24, and the third vibration element 31 are based on audio signals, and can be considered as AC voltages according to the frequency of the audio to be generated. In FIG. 6, the AC voltage supplied to the first vibration element 11 is V1, and the AC voltage supplied to the second vibration elements 21-24 and the third vibration element 31 is V2. One terminal of the AC power supply is connected to the electrodes 111, 211, 221, 231, 241, and 311, and the other terminal can be connected to the electrodes 113, 213, 223, 233, 243, and 313. Although two AC power supplies are shown in FIG. 6, one AC power supply can be used. For example, a drive signal may be supplied from one (common) AC power source to the first vibration element 11, and a signal with an inverted phase of the drive signal may be supplied as a common drive signal to the second vibration elements 21-24 and the third vibration element 31. For example, one terminal of the common AC power source may be connected to the electrodes 111, 213, 223, 233, 243, and 313, and the other terminal may be connected to the electrodes 113, 211, 221, 231, 241, and 311.

[0058] When an AC voltage is applied between the electrodes 111 and 113 of the first vibration element 11, the vibration layer 112 expands and contracts, and a periodic stress is applied to the vibration member 90. For example, the first vibration element 11 transmits a periodic stress to the vibration member 90, and the transmitted stress causes the vibration member 90 to perform bending vibration. The vibration of the vibration member 90 based on the transmitted stress generates a vibration based on an audio signal, for example, sound. Similarly, when an AC voltage is applied between the electrodes 211, 221, 231, 241 and the electrodes 213, 223, 233, 243 of the second vibration elements 21 to 24, the vibration layers 212, 222, 232, 242 expand and contract, and a periodic stress is applied to the vibration member 90 via the elastic members 41 to 44. Furthermore, when an AC voltage is applied between the electrodes 311 and 313 of the third vibration element 31, the vibration layer 312 expands and contracts, and a periodic stress can be transmitted to the vibration member 90 via the elastic member 51 and the first vibration element 11. The transmitted stress causes the vibration member 90 to undergo bending vibration, and vibrations and / or sounds based on an audio signal are generated.

[0059] The material of each vibration layer 112, 212, 222, 232, 242, 312 is not particularly limited, but since it can increase the amount of displacement, a material with good piezoelectricity such as lead zirconate titanate can be used. As another example, the material used for each vibration layer 112, 212, 222, 232, 242, 312 may include a ceramic-based piezoelectric material that can achieve relatively high vibration. As yet another example, each vibration layer 112, 212, 222, 232, 242, 312 may include a piezoelectric ceramic material having a crystal structure of a Perovskite series. Also, each vibration layer 112, 212, 222, 232, 242, 312 may have a polycrystalline structure, but may also have a single crystal structure. For example, each vibration layer 112, 212, 222, 232, 242, 312 may be made of polycrystalline ceramic or single crystal ceramic. Also, each vibration layer 112, 212, 222, 232, 242, 312 may be made of a material containing a piezoelectric material including PVDF (polyvinylidene fluoride) or lead (Pb), but may also be made of a piezoelectric material that does not contain lead. The piezoelectric material including lead may include, for example, one or more of a PZT (Lead Zirconate Titanate) material, a PZNN (Lead Zirconate Nickel Niobate) material, a PMN (Lead Magnesium Niobate) material, a PNN (Lead Nickel Niobate) material, a PZN (Lead Zirconate Niobate) material, and a PIN (Lead Indium Niobate) material. Additionally, lead-free piezoelectric materials may include, for example, one or more of barium titanate (BaTiO3), calcium titanate (CaTiO3), and strontium titanate (SrTiO3), but embodiments herein are not limited thereto.

[0060] The adhesive members 61, 62, 63, 64, 65, and 66 may be a pressure-bonding resin material, an adhesive, an adhesive tape, or the like, but the embodiments of the present specification are not limited thereto. The elastic modulus of the adhesive member 61 and the adhesive layer 62 may be the same or different from each other. For example, the adhesive member 61 may have a lower elastic modulus than the adhesive member 62. Furthermore, each side of the first vibration element 11, the second vibration elements 21 to 24, and the third vibration element 31 may be covered with an insulator such as a resin to prevent shorting with other members.

[0061] The material of the first electrode and the second electrode (111, 113, 211, 213, 221, 223, 231, 233, 241, 243, 311, 313) of the first vibration element 11, the second vibration element 21, and the third vibration element 31 may include a transparent conductive material, a semi-transparent conductive material, or an opaque conductive material. For example, as a transparent or semi-transparent conductive material, the first electrode and the second electrode may include one or more of ITO (indium tin oxide) or IZO (indium zinc oxide), but the embodiment of the present specification is not limited thereto. As an opaque conductive material, the first electrode and the second electrode may include one or alloys of aluminum (Al), copper (Cu), gold (Au), silver (Ag), molybdenum (Mo), or magnesium (Mg), but the embodiment of the present specification is not limited thereto. For example, the protective layers 117, 118, 227, 228, 237, 238, 317, 318 may be a polyimide film, a polyethylene terephthalate film, or a polyethylene naphthalate film, although embodiments herein are not limited thereto.

[0062] The improvement of the sound quality of the acoustic device according to this embodiment will be described with reference to actual measurement data. FIG. 7 is a graph showing the acoustic characteristics of the acoustic device according to this embodiment. The horizontal axis of FIG. 7 is frequency (Hz) on a logarithmic scale, and the vertical axis is sound pressure in decibels (dB). The curve shown by the solid line in FIG. 7 is the acoustic characteristics of the acoustic device 1 of this embodiment when the phases of the drive signals (or audio signals) input to the second vibration elements 21-24 and the third vibration element 31 are reversed to the phase of the drive signal input to the first vibration element 11. The curve shown by the dashed dotted line is the acoustic characteristics of the acoustic device (hereinafter referred to as "experimental example") when the phases of the drive signals (or audio signals) input to the first vibration element 11, the second vibration elements 21-24, and the third vibration element 31 are made the same. The experimental example has the same structure as the acoustic device 1 of this embodiment shown in FIGS. 2 to 6.

[0063] In FIG. 7, when comparing the curves below 3 kHz, it is understood that the frequency characteristics are roughly similar. On the other hand, when comparing the curves around 3 kHz to 10 kHz, the amplitude is greatly reduced in the configuration according to the experimental example. In the configuration according to this embodiment, no significant reduction in amplitude is observed around 3 kHz, and a higher amplitude is observed in the entire frequency band from 3 kHz to 10 kHz compared to the configuration according to the experimental example. For example, when compared to the experimental example, the acoustic device 1 according to this embodiment can provide a relatively flat frequency characteristic in a wide frequency band from the bass region to the treble region. Therefore, the acoustic device 1 according to this embodiment can improve the flatness characteristic of the sound pressure and improve the sound quality.

[0064] [Second embodiment] The acoustic device 1 according to the second embodiment will be described below. The first vibration element 11, the second vibration elements 21 and 22, the third vibration element 31, the elastic members 41, 42, and 51, and the vibration member 90 have the same configurations as those in the first embodiment, and therefore will not be described.

[0065] FIG. 8 is a perspective view showing the configuration of an acoustic device 1 according to this embodiment. FIG. 9 is a plan view showing the configuration of an acoustic device according to this embodiment. FIG. 10 is a cross-sectional view showing the configuration of an acoustic device according to this embodiment. FIG. 11 is a cross-sectional view showing the structure of a vibration element according to this embodiment in more detail. FIGS. 10 and 11 show cross-sectional views taken along line A-A' in FIG. 9 according to this embodiment. The specific configuration of the acoustic device 1 according to this embodiment will be described with mutual reference to FIGS. 8 to 11.

[0066] 8, the acoustic device 1 according to this embodiment differs from the acoustic device 1 according to the first embodiment in that it does not have the second vibration elements 23, 24 and the elastic members 43, 44. For example, the acoustic device 1 according to this embodiment can include a first vibration element 11, second vibration elements 21, 22, a third vibration element 31, elastic members 41, 42, 51 and a vibration member 90.

[0067] The second vibration elements 21, 22 may be disposed above the first vibration element 11. Parts of the second vibration elements 21, 22 may overlap the first vibration element 11 and the third vibration element 31 in a plan view. The second vibration elements 21, 22 do not directly contact the first vibration element 11. The second vibration elements 21, 22 may be disposed rotationally symmetrically about the z axis in a plan view. Specifically, the two second vibration elements 21, 22 may each have a two-fold symmetry property about the z axis. The second vibration elements 21, 22 may be disposed so as not to contact each other. A part of the first main surface 21a of the second vibration element 21 may be connected to a part of the main surface of the vibration member 90 via the elastic member 41 (or the first elastic member). Similarly, a part of the first main surface 22a of the second vibration element 22 may be connected to a part of the main surface of the vibration member 90 via the elastic member 42. The heights of the elastic members 41, 42 in the z axis direction in a cross-sectional view may be the same. Therefore, the second vibration elements 21 and 22 can be disposed at the same position (or height) in the z-axis direction. Therefore, the second vibration elements 21 and 22 do not overlap each other in a plan view. Vibrations generated from the second vibration elements 21 and 22 by the input drive signal (or audio signal) can be transmitted to the vibration member 90 via the elastic members 41 and 42, respectively.

[0068] The first vibration element 11 may be connected to the vibration member 90 by an adhesive member 61 (or a first adhesive member). A part of the second main surface 21b of the second vibration element 21 may be connected to the first main surface 31a of the third vibration element 31 by an adhesive member 62. A part of the second main surface 22b of the second vibration element 22 may be connected to the first main surface 31a of the third vibration element 31 by an adhesive member 62. A corner of the first main surface 31a of the third vibration element 31 may be connected to a corner of the second main surface 11b of the first vibration element 11 via four elastic members 51. The elastic members 41, 42 may be connected to the vibration elements 21, 22 and the vibration member 90 via adhesive members 63, 64 (or adhesive or adhesive layer). For example, the elastic members 41, 42 may be connected to the vibration member 90 via the adhesive member 63 (or a third adhesive member). For example, the elastic members 41 to 44 may be connected to the vibration elements 21, 22 via an adhesive member 64 (or a fourth adhesive member). For example, the elastic member 51 may be connected to the vibration element 11 via an adhesive member 65 (or a fifth adhesive member). For example, the elastic member 51 may be connected to the third vibration element 31 via an adhesive member 66 (or a sixth adhesive member).

[0069] An example of the structure of the acoustic device 1 will be described in more detail with reference to Fig. 11. Fig. 11 is an enlarged view of the first vibration element 11, the second vibration elements 21 and 22, and the third vibration element 31 in the same cross section as Fig. 10. Fig. 11 also shows a schematic circuit diagram of the connection relationship of the electrodes included in the first vibration element 11, the second vibration elements 21 and 22, and the third vibration element 31 in order to explain a method of inputting a drive signal to the acoustic device 1. Explanations of configurations that overlap with the first embodiment may be omitted.

[0070] A voltage V1 may be applied to the vibration layer 112 of the first vibration element 11 via the electrodes 111 and 113. The voltage V1 may correspond to a driving signal (or an audio signal). The second vibration element 21 and the second vibration element 22 may have a structure similar to that of the second vibration element 23 according to the first embodiment shown in FIG. 6. For example, the second vibration element 21 may include an electrode 211 (or a first electrode), a vibration layer 212 (or a piezoelectric layer), an electrode 213 (or a second electrode), a protective layer 217 (or a first protective member), and a protective layer 218 (or a second protective member). The electrodes 211 and 213 are arranged to sandwich the vibration layer 212 in the thickness direction. A voltage V2 is applied to the vibration layer 212 via a signal line, the electrode 211, and the electrode 213. Similarly, the second vibration element 22 may include an electrode 221 (or a first electrode), a vibration layer 222 (or a piezoelectric layer), an electrode 223 (or a second electrode), a protective layer 227 (or a first protective member), and a protective layer 228 (or a second protective member). The electrode 221 and the electrode 223 are arranged to sandwich the vibration layer 222 in the thickness direction. A voltage V2 may be applied to the vibration layer 222 via the signal line, the electrode 221, and the electrode 223. The voltage V2 corresponds to a drive signal (or an audio signal) and may have an opposite phase to the voltage V1 applied to the first vibration element 11. The voltage V2 may be applied to the vibration layer 312 of the third vibration element 31 via the electrode 311 and the electrode 313. The voltage V2 may correspond to a drive signal (or an audio signal) commonly applied to the second vibration elements 21, 22, and the third vibration element 31. For example, the voltage V2 applied to the third vibration element 31 can have an opposite phase to the voltage V1 applied to the first vibration element 11.

[0071] The voltages applied to the first vibration element 11, the second vibration element 21, the second vibration element 22, and the third vibration element 31 are based on audio signals, and can be considered as AC voltages according to the frequency of the audio to be generated. In FIG. 11, the AC voltage supplied to the first vibration element 11 is V1, and the AC voltage supplied to the second vibration elements 21, 22, and the third vibration element 31 is V2. One terminal of the AC power supply may be connected to the electrodes 111, 211, 221, and 311, and the other terminal may be connected to the electrodes 113, 213, 223, and 313. Although two AC power supplies are shown in FIG. 6, one AC power supply may be used. For example, a drive signal may be supplied from one (or a common) AC power supply to the first vibration element 11, and a signal with the phase of the drive signal inverted may be supplied to the second vibration elements 21 to 24 and the third vibration element 31 as a common drive signal. For example, one terminal of a common AC power source may be connected to electrodes 111, 213, 223, and 313, and the other terminal may be connected to electrodes 113, 211, 221, and 311.

[0072] When an AC voltage is applied between the electrode 111 and the electrode 113 of the first vibration element 11, the vibration layer 112 expands and contracts, and a periodic stress is applied to the vibration member 90. For example, the first vibration element 11 transmits a periodic stress to the vibration member 90, and the transmitted stress can cause the vibration member 90 to perform bending vibration. The vibration of the vibration member 90 based on the transmitted stress generates a vibration based on an audio signal, for example, sound. Similarly, when AC voltages are applied between the electrodes 211, 221 and the electrodes 213, 223 of the second vibration elements 21, 22, respectively, the vibration layers 212, 222 expand and contract, and a periodic stress is applied to the vibration member 90 via the elastic members 41, 42. Also, when an AC voltage is applied between the electrode 311 and the electrode 313 of the third vibration element 31, the vibration layer 312 expands and contracts, and a periodic stress can be transmitted to the vibration member 90 via the elastic member 51 and the first vibration element 11. The transmitted stress causes the vibrating member 90 to vibrate and generate vibrations and / or sounds based on the audio signal.

[0073] In this embodiment, two second vibration elements 21 and 22 are used in the acoustic device 1. Also, in the first embodiment, four second vibration elements 21 to 24 are used in the acoustic device 1. However, the number of second vibration elements arranged in the acoustic device 1 according to the present disclosure is not limited to two or four. Specifically, the second vibration elements may be arranged rotationally symmetrically about the z-axis in a plan view. For example, the acoustic device 1 according to the present disclosure may have six second vibration elements. For example, the second vibration elements according to the present disclosure may be arranged in the acoustic device 1 so as to have a six-fold symmetry property. In this case, each of the second vibration elements may be arranged so as to extend in a direction rotated by 60 degrees from the longitudinal direction of the adjacent second vibration element in a plan view.

[0074] In the first and second embodiments, a part of the second main surface (e.g., the second main surface 21b, 22b) of each second vibration element may be connected to a part of the first main surface 31a of the third vibration element. However, the acoustic device 1 according to the present disclosure may be configured such that a part of the first main surface (e.g., the first main surface 21a, 22a) of the second vibration element is connected to a part of the second main surface 31b of the third vibration element. For example, as a modification of the first embodiment, a part of the second main surface 31b of the third vibration element 31 may be connected to a part of the first main surfaces 21a, 22a, 23a, 24a of each of the second vibration elements 21 to 24 via an adhesive member (or an adhesive layer or adhesive). In the first embodiment, the second vibration elements 21 to 24 may be arranged so as to extend radially from the third vibration element 31 in a plan view. In this case, the second vibration elements 21 and 22 may be arranged so that the longitudinal direction is parallel to the second direction (y-axis direction). The second vibration element 21 and the second vibration element 22 may be arranged such that their short sides in plan view face each other with a predetermined space between the first vibration element and the third vibration element. The second vibration elements 23 and 24 may be arranged such that their longitudinal directions are parallel to the first direction (x-axis direction). The second vibration element 23 and the second vibration element 24 may be arranged such that their short sides in plan view face each other with a predetermined space between the first vibration element and the third vibration element. In the modified example of the second embodiment, the second vibration elements 21 and 22 may be arranged in the same configuration as in the modified example of the first embodiment.

[0075] [Third embodiment] In this embodiment, a modified example of the structure of the vibration element in the acoustic device 1 according to the third embodiment will be described. Fig. 12 is a plan view showing the structure of the vibration element according to this embodiment. Fig. 13 is a cross-sectional view taken along line DD' in Fig. 12 according to this embodiment.

[0076] As shown in FIGS. 12 and 13, the vibration element 11 according to this embodiment can include a vibration generating section (or a vibration section) 11A.

[0077] The vibration generating unit 11A may include a vibration layer 112, a first electrode 111 on a first surface of the vibration layer 112, and a second electrode 113 on a second surface of the vibration layer 112 different from the first surface. The vibration layer 112 may be substantially the same as the vibration layer 112 described in FIG. 6, so a duplicated description thereof will be omitted. The first electrode 111 and the second electrode 113 are arranged to sandwich the vibration layer 112 in the thickness direction, and apply a voltage to the vibration layer 112. The polarization direction of the vibration layer 112 may be the positive direction or the negative direction of the z axis. Wiring for applying a voltage to each electrode may be connected to the first electrode 111 and the second electrode 113.

[0078] The vibration element 11 according to this embodiment may further include a first protective layer (or a first protective member) 117 and a second protective layer (or a second protective member) 118. The first protective layer 117 may be connected to a first surface (or a front surface or a top surface) of the vibration generating unit 11A. The first protective layer 117 protects and insulates the first surface of the vibration generating unit 11A. The second protective layer 118 may be connected to a second surface (or a back surface or a bottom surface) of the vibration generating unit 11A. The second protective layer 118 protects and insulates the second surface of the vibration generating unit 11A. For example, any one of the first protective layer 117 and the second protective layer 118 of the vibration elements 11, 12, 13, and 14 may be connected to the vibration member via adhesive layers 119a and 119b. For example, the adhesive layers 119a and 119b may be made of an adhesive resin material, an adhesive, an adhesive tape, or the like, but the embodiment of the present specification is not limited thereto. The adhesive layers 119a, 119b may include an epoxy-based, an acrylic-based, a silicone-based, or a urethane-based material, and embodiments herein are not limited thereto.

[0079] The first protective layer 117 may be connected or bonded to the first electrode 111 via a first adhesive layer 119a. The second protective layer 118 may be connected or bonded to the second electrode 113 via a second adhesive layer 119b. The first adhesive layer 119a and the second adhesive layer 119b may be configured between the first protective layer 117 and the second protective layer 118 so as to completely surround the vibration generating unit 11A. For example, the vibration generating unit 11A may be embedded or built-in between the first adhesive layer 119a and the second adhesive layer 119b. For example, the first protective layer 117 and the second protective layer 118 may be a polyimide film, a polyethylene terephthalate film, or polyethylene naphthalate, but the embodiments of the present specification are not limited thereto.

[0080] The structures of the vibration elements 21, 22, 23, 24, and 31 according to this embodiment are similar to those of the third embodiment, and therefore will not be described.

[0081] [Fourth embodiment] In this embodiment, a modified example of the structure of the vibration layer in the vibration element of the acoustic device 1 according to the fourth embodiment will be described. Fig. 14 is a perspective view showing the vibration layer in the vibration element of the acoustic device according to this embodiment.

[0082] 14, the vibration layer 112 of the vibration generating section 11A in the vibration element 11 according to this embodiment can include a plurality of first portions 112a and one or more second portions 112b. For example, the vibration layer 112 can include a plurality of first portions 112a and a plurality of second portions 112b between the plurality of first portions 112a. For example, the plurality of first portions 112a and the plurality of second portions 112b can be alternately and repeatedly arranged along the x-axis direction, but the embodiment of the present specification is not limited thereto.

[0083] Each of the plurality of first portions 112a may include an inorganic material having a piezoelectric characteristic. For example, each of the plurality of first portions 112a may be an inorganic material portion or a piezoelectric material portion. Each of the plurality of first portions 112a may have a first width parallel to the x-axis direction and extend along the y-axis direction. Each of the plurality of first portions 112a may be substantially the same as the vibration layer 112 described in FIG. 6, and therefore, a duplicate description thereof will be omitted.

[0084] Each of the second portions 112b may be disposed between the first portions 112a. For example, each of the first portions 112a may be disposed between two adjacent second portions 112b among the second portions 112b. For example, the first portions 112a and the second portions 112b may include line or stripe shapes having the same or different sizes.

[0085] Each of the plurality of second portions 112b may be configured to fill a gap between two adjacent first portions 112a. Each of the plurality of first portions 112a and each of the plurality of second portions 112b may be arranged (or aligned) parallel to each other on the same plane (or the same layer). Each of the plurality of second portions 112b may improve the durability of the first portion 112a by absorbing an impact applied to the first portion 112a, and may provide flexibility to each of the first vibration element 11 and the second vibration element 21. Each of the plurality of second portions 112b may include an organic material having soft properties. For example, the plurality of second portions 112b may be one or more of an epoxy-based polymer, an acrylic-based polymer, and a silicone-based polymer, but the embodiments herein are not limited thereto. For example, each of the plurality of second portions 112b may be expressed as an organic part, an organic material, an adhesive part, an elastic part, a bending part, a damping part, an elastic part, a resilient part, or a soft part, but the embodiments herein are not limited thereto.

[0086] A first surface of each of the first portions 112a and the second portions 112b may be commonly coupled to a first electrode. A second surface of each of the first portions 112a and the second portions 112b may be commonly coupled to a second electrode.

[0087] The vibration layer 112 in the vibration element 11 of the acoustic device 1 according to the fourth embodiment can have a single thin film shape by arranging (or connecting) a plurality of first portions 112a and second portions 112b on the same plane. This allows the vibration element 11 to vibrate in the up and down direction by the first portions 112a having vibration characteristics, and to bend into a curved shape by the second portions 112b having flexibility. For example, the vibration element 11 including the vibration layer 112 can have a resonance frequency of 20 kHz or less by having a 2-2 composite structure, but the embodiments of the present specification are not limited thereto.

[0088] The structures of the vibration elements 21, 22, 23, 24, and 31 according to this embodiment are similar to those of the fourth embodiment, and therefore description thereof will be omitted.

[0089] [Fifth embodiment] In this embodiment, a description will be given of another modified example of the structure of the vibration layer in the vibration element of the acoustic device 1 according to the tenth embodiment. Fig. 15 is a perspective view showing the vibration layer in the vibration element of the acoustic device according to this embodiment.

[0090] 15, the vibration layer 112 of the vibration generating section 11A in the vibration element 11 according to this embodiment can include a plurality of first portions 112a and a second portion 112b. For example, the vibration layer 112 can include a plurality of first portions 112a and a second portion 112b disposed between the plurality of first portions 112a.

[0091] The first portions 112a may be arranged to be spaced apart from one another along the x-axis direction and the y-axis direction. For example, the first portions 112a may be arranged in a lattice shape having hexahedral shapes of the same size. Each of the first portions 112a may be substantially the same as the first portion 112a described in FIG. 14, and therefore a duplicate description thereof will be omitted.

[0092] The second portion 112b may be disposed between the first portions 112a along each of the x-axis direction and the y-axis direction. The second portion 112b may be connected or bonded to the adjacent first portions 112a by filling a gap between two adjacent first portions 112a or by being configured to surround each of the first portions 112a. The second portion 112b may be substantially the same as the second portion 112b described in FIG. 14, and therefore a duplicate description thereof will be omitted.

[0093] A first surface of each of the plurality of first portions 112a and the second portions 112b may be commonly coupled to a first electrode, and a second surface of each of the plurality of first portions 112a and the second portions 112b may be commonly coupled to a second electrode.

[0094] The vibration layer 112 in the vibration element 11 of the acoustic device 1 according to the fifth embodiment can have a single thin film shape by arranging (or connecting) a plurality of first portions 112a and second portions 112b on the same plane. This allows the vibration element 11 to vibrate in the up and down direction by the first portions 112a having vibration characteristics, and to bend into a curved shape by the second portions 112b having flexibility. For example, the vibration element 11 including the vibration layer 112 can have a resonance frequency of 20 kHz or less by having a 1-3 composite structure, but the embodiments of the present specification are not limited thereto.

[0095] The structures of the vibration elements 21, 22, 23, 24, and 31 according to this embodiment are similar to those of the fifth embodiment, and therefore will not be described.

[0096] [Sixth embodiment] In this embodiment, a specific configuration example will be described in which the acoustic device 1 according to the first embodiment is a display device and the vibrating member 90 also functions as a display panel of the display device. Descriptions of elements common to the first embodiment may be omitted or simplified.

[0097] 16 is a configuration diagram of a display device 70 according to a sixth embodiment. The display device 70 of this embodiment may be used, for example, as an electronic poster, a digital bulletin board, an electronic billboard, a computer screen, a television receiver, etc., but the embodiment of this specification is not limited thereto. The structures of the host system 7, the first vibration element 11, the second vibration elements 21-24, and the third vibration element 31 are similar to those of the first embodiment, and therefore description thereof will be omitted. In addition, the elastic members 41-44, 51, etc. of the first embodiment are connected to the first vibration element 11, the second vibration elements 21-24, and the third vibration element 31.

[0098] 16, the display device 70 may have an acoustic device including a first vibration element 11, second vibration elements 21-24 and a third vibration element 31, a control unit 200, a panel control unit 300, a data driving circuit 400, a gate driving circuit 500 and a display panel 600. The display device 70 may be a device that displays an image on the display panel 600 based on input RGB data or the like, and emits sound based on input driving signals or the like.

[0099] The panel control unit 300 can control the data driving circuit 400 and the gate driving circuit 500 based on image data and timing signals input from the host system 7. The data driving circuit 400 can supply data voltages and the like to the pixels (P) via driving lines 410 arranged for each column of the pixels (P). The gate driving circuit 500 can supply control signals to the pixels (P) via driving lines 510 arranged for each row of the pixels (P). Each of the driving lines 410 and the driving lines 510 can be composed of a plurality of wirings.

[0100] The display panel 600 may include a plurality of pixels (P) arranged in a plurality of rows and a plurality of columns. If the display device 70 is capable of displaying a color image, the pixels (P) may be sub-pixels that display any of a plurality of colors (e.g., RGB or RGBW) that make up the color image.

[0101] The display panel 600 used in one or more embodiments of the present specification may be a display panel of any shape, such as a liquid crystal display panel, an organic light-emitting display panel, and an electroluminescent display panel, and the embodiments of the present specification are not limited thereto. For example, the display panel 600 may be a display panel that can generate sound by being vibrated by an acoustic device according to an embodiment of the present specification. The display panel 600 applied to the display device 70 according to an embodiment of the present specification is not limited to the shape or size of the display panel 600.

[0102] According to one or more embodiments herein, when the display panel 600 is a liquid crystal display panel, the display panel 600 may include a plurality of gate lines, a plurality of data lines, and a plurality of pixels (P) formed at each of the intersection regions of the gate lines and the data lines. The display panel 600 may include an array substrate including thin film transistors that are switching elements for adjusting the light transmittance of each pixel (P), an upper substrate including a color filter and / or a black matrix, and a liquid crystal layer formed between the array substrate and the upper substrate.

[0103] When the display panel 600 is an organic light emitting display panel, the display panel 600 may include a plurality of gate lines, a plurality of data lines, and a plurality of pixels (P) formed at each of the intersection regions of the gate lines and the data lines. The display panel 600 may include an array substrate including a thin film transistor, which is an element for selectively applying a voltage to each pixel (P), an organic light emitting element layer on the array substrate, and a sealing substrate or encapsulation substrate disposed on the array substrate to cover the organic light emitting element layer. The sealing substrate may protect the thin film transistor and the organic light emitting element layer from external impact and prevent moisture or oxygen from penetrating into the organic light emitting element layer. The layer formed on the array substrate may include an inorganic light emitting layer, for example, a nano-sized material layer, and a quantum dot light emitting layer. In another embodiment of the present specification, the layer formed on the array substrate may include a micro light emitting diode.

[0104] The display panel 600 may further include a backing, such as a metal plate, attached to the display panel 600. The display panel 600 may also include other structures, for example, other structures made of other materials.

[0105] Each of the control unit 200, the panel control unit 300, the data driving circuit 400, and the gate driving circuit 500 may be configured by one or more semiconductor integrated circuits. In addition, some or all of the control unit 200, the panel control unit 300, the data driving circuit 400, and the gate driving circuit 500 may be integrated into one semiconductor integrated circuit.

[0106] The display device 70 of this embodiment can display an image and / or emit a sound by receiving an image signal (e.g., RGB data or RGBW data), a drive signal, and a timing signal (e.g., a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, etc.) from the host system 7. The display panel 600 can have an image display surface that displays an image, and a back surface that faces the image display surface. The first vibration element 11, the second vibration elements 21 to 24, and the third vibration element 31 can be connected to the back surface of the display panel 600. For example, the vibration generated by the first vibration element 11, the second vibration elements 21 to 24, and the third vibration element 31 can be transmitted to the back surface of the display panel 600. The display panel 600 can have a function of image display and a function of the vibration member 90 in the first embodiment. In this embodiment, a display device 70 having an acoustic effect in which a sound is generated from an image displayed on the display panel 600 can be provided.

[0107] The acoustic device according to the embodiment of the present specification may be applied to an acoustic device arranged in an apparatus. The apparatus according to the embodiment of the present specification may be applied to a mobile device, a video phone, a smart watch, a watch phone, a wearable apparatus, a foldable apparatus, a rollable apparatus, a bendable apparatus, a flexible apparatus, a curved apparatus, a sliding apparatus, a variable apparatus, an electronic organizer, an electronic book, a portable multimedia player (PMP), a personal digital assistant (PDA), an MP3 player, a mobile medical device, a desktop PC, a laptop PC, a netbook computer, a workstation, a navigation system, a vehicle navigation system, a vehicle display device, a vehicle device, a theater device, a theater display device, a television, a wallpaper device, a signage device, a game device, a notebook, a monitor, a camera, a video camera, and a home appliance. The acoustic device of the present specification may be applied to an organic light-emitting lighting device or an inorganic light-emitting lighting device. When the acoustic device is applied to a lighting device, the lighting device may play the role of lighting and a speaker. When the acoustic device of the present specification is applied to a mobile device or the like, the acoustic device may be one or more of a speaker, a receiver, and a haptic device, and the embodiment of the present specification is not limited thereto.

[0108] The acoustic device according to the embodiment of the present specification can be described as follows.

[0109] An acoustic device according to an embodiment of the present specification includes a vibration member having a flat plate shape, and a first vibration element, a plurality of second vibration elements, and a third vibration element, each of which has a flat plate shape including first and second main surfaces facing each other and is configured to vibrate in response to an input drive signal, wherein the first main surface of the first vibration element is connected to the vibration member, and a portion of the second main surface of the first vibration element and a portion of the first main surface of the third vibration element are connected via an elastic member so that the first main surface of the third vibration element faces the second main surface of the first vibration element at a predetermined distance, and a portion of each of the plurality of second vibration elements is connected to a portion of the third vibration element and a portion of the first main surface of each of the plurality of second vibration elements is connected to a portion of the vibration member via an elastic member so that the plurality of second vibration elements extend radially from the third vibration element in a planar view, and the drive signal input to the first vibration element can have a phase different from the phase of the drive signal input to the third vibration element.

[0110] According to one or more embodiments herein, the drive signal input to the third vibration element may have the same phase as the phase of the drive signal input to the plurality of second vibration elements.

[0111] According to one or more embodiments herein, the multiple second vibration elements may be arranged rotationally symmetrically about an axis perpendicular to the first and second main surfaces of the third vibration element.

[0112] According to one or more embodiments of the present specification, a portion of each of the multiple second vibration elements connected to the third vibration element may not overlap a portion of the first principal surface of each of the multiple second vibration elements in a planar view.

[0113] According to one or more embodiments herein, a portion of the second major surface of each of the plurality of second vibration elements may be connected to a portion of the first major surface of the third vibration element.

[0114] According to one or more embodiments herein, the plurality of second vibration elements may be connected to the third vibration element via an adhesive member.

[0115] According to one or more embodiments herein, the multiple second vibration elements may not overlap each other in a plan view.

[0116] According to one or more embodiments herein, the sensor may include two or more second vibration elements, or may include four or more second vibration elements.

[0117] According to one or more embodiments of the present specification, the first vibration element has the same shape as the flat plate shape of the third vibration element, and the entire second main surface of the first vibration element can be covered by the third vibration element in a plan view.

[0118] According to one or more embodiments herein, the second main surface of the first vibration element and the first main surface of the third vibration element are rectangular, and a portion of the second main surface of the first vibration element and a portion of the first main surface of the third vibration element may be corners of the rectangle.

[0119] According to one or more embodiments herein, the entirety of the first major surface of the first vibrating element may be in contact with the vibrating member.

[0120] According to one or more embodiments herein, the first vibration element and the second vibration element may not be in direct contact with each other.

[0121] According to one or more embodiments herein, the first vibration element may overlap a portion of the second vibration element that is connected to the third vibration element in a plan view.

[0122] According to one or more embodiments herein, at least one of the first vibration element, the second vibration element, and the third vibration element may be a piezoelectric element.

[0123] An acoustic device according to an embodiment of the present specification includes a vibrating member, a first vibration element connected to the vibrating member, a third vibration element superimposed on the first vibration element, a plurality of second vibration elements connected to the vibrating member and connected to the third vibration element between the first vibration element and the third vibration element so as to be spaced apart from the first vibration elements, a plurality of elastic members connected between each of the plurality of second vibration elements and the vibrating member, and a plurality of connecting members connected between the first vibration element and the third vibration element, and a drive signal input to the first vibration element can have a phase different from the phase of the drive signal input to the third vibration element.

[0124] According to one or more embodiments herein, the drive signal input to the third vibration element may have the same phase as the phase of the drive signal input to the plurality of second vibration elements.

[0125] According to one or more embodiments of the present disclosure, the first vibration element may be coupled to the vibration member by a full-surface adhesive method using an adhesive member.

[0126] According to one or more embodiments herein, each of the plurality of second vibration elements may include a first end coupled to the vibration member via a corresponding elastic member and a second end coupled to the third vibration element via a corresponding connecting member.

[0127] In accordance with one or more embodiments herein, the vibrating member includes at least one of the following materials: metal, resin, glass, wood, rubber, plastic, fiber, cloth, paper, leather, or carbon, and the vibrating member may be at least one of a display panel including pixels configured to display an image, a screen panel onto which an image is projected from a display device, a lighting panel, a light emitting diode lighting panel, an organic light emitting lighting panel, an inorganic light emitting lighting panel, a signage panel, an interior material of a vehicle, a glass window of a vehicle, an exterior material of a vehicle, a seat interior material of a vehicle, a ceiling material of a vehicle, a ceiling material of a building, an interior material of a building, a glass window of a building, an interior material of an aircraft, a glass window of an aircraft, and a mirror.

[0128] According to one or more embodiments herein, the vibration member is a display panel of a display device, the display panel including an image display surface on which an image is displayed and a back surface opposite the image display surface, and vibrations generated by the first vibration element, the second vibration element and the third vibration element can be transmitted to the back surface of the display panel.

[0129] The present specification described above is not limited to the above-mentioned embodiment and the attached drawings, and various substitutions, modifications and changes are possible within the scope of the technical idea of ​​the specification. Therefore, the scope of the specification is indicated by the claims described below, and all modifications or variations derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the specification. [Explanation of symbols]

[0130] 1 Sound equipment 11 First vibration element 21 to 24 Second vibration element 31 Third vibration element 41 to 44, 51 Elastic member 90 Vibration member

Claims

1. A vibration member having a flat plate shape; The vibration device includes a first vibration element, a plurality of second vibration elements, and a third vibration element, each of which has a flat plate shape including a first main surface and a second main surface facing each other, and is configured to vibrate in response to an input drive signal; The first main surface of the first vibration element is connected to the vibration member, a part of the second main surface of the first vibration element and a part of the first main surface of the third vibration element are connected via an elastic member such that the first main surface of the third vibration element faces the second main surface of the first vibration element at a predetermined distance; a portion of each of the second vibration elements is connected to a portion of the third vibration element such that the second vibration elements extend radially from the third vibration element in a plan view, and a portion of the first main surface of each of the second vibration elements is connected to a portion of the vibration member via an elastic member; The drive signal input to the first vibration element has a phase different from a phase of the drive signal input to the third vibration element. sound equipment.

2. The drive signal input to the third vibration element has the same phase as a phase of the drive signal input to the second vibration elements.

2. An acoustic device according to claim 1.

3. The plurality of second vibration elements are arranged rotationally symmetrically about an axis perpendicular to the first principal surface and the second principal surface of the third vibration element.

2. An acoustic device according to claim 1.

4. The acoustic device according to claim 3 , wherein the portion of each of the plurality of second vibration elements connected to the third vibration element does not overlap the portion of the first main surface of each of the plurality of second vibration elements in a plan view.

5. A portion of the second main surface of each of the plurality of second vibration elements is connected to a portion of the first main surface of the third vibration element.

5. An acoustic device according to claim 4.

6. The plurality of second vibration elements are connected to the third vibration element via an adhesive member.

6. An acoustic device according to claim 5.

7. The second vibration elements do not overlap with each other in a plan view.

4. An acoustic device according to claim 3.

8. The second vibration element may include two or more of the second vibration elements, or may include four or more of the second vibration elements.

8. An acoustic device as claimed in claim 7.

9. The first vibration element has the same shape as the flat plate shape of the third vibration element, The entire second principal surface of the first vibration element is covered by the third vibration element in a plan view.

2. An acoustic device according to claim 1.

10. the second main surface of the first vibration element and the first main surface of the third vibration element are rectangular, the portion of the second main surface of the first vibration element and the portion of the first main surface of the third vibration element are corners of the rectangle; 11. An acoustic device as claimed in claim 10.

11. The entire first main surface of the first vibration element is in contact with the vibration member.

10. An acoustic device as claimed in claim 9.

12. The first vibration element and the second vibration element are not in direct contact with each other.

12. An acoustic device as claimed in claim 11.

13. the first vibration element overlaps with the portion of the second vibration element connected to the third vibration element in a plan view; 13. An acoustic device as claimed in claim 12.

14. At least one of the first vibration element, the second vibration element, and the third vibration element is a piezoelectric element.

2. An acoustic device according to claim 1.

15. A vibrating member; A first vibration element coupled to the vibration member; a third vibration element superimposed on the first vibration element; a plurality of second vibration elements connected to the vibration member and connected to the third vibration element between the first vibration element and the third vibration element so as to be spaced apart from the first vibration element; a plurality of elastic members connected between each of the plurality of second vibration elements and the vibration member; a plurality of connecting members connected between the first vibration element and the third vibration element; The drive signal input to the first vibration element has a phase different from a phase of the drive signal input to the third vibration element. sound equipment.

16. The drive signal input to the third vibration element has the same phase as a phase of the drive signal input to the second vibration elements.

16. An acoustic device as claimed in claim 15.

17. The first vibration element is connected to the vibration member by a full surface adhesion method using an adhesive material.

16. An acoustic device as claimed in claim 15.

18. Each of the second vibration elements includes a first end connected to the vibration member via the corresponding elastic member, and a second end connected to the third vibration element via the corresponding connecting member.

16. An acoustic device as claimed in claim 15.

19. The vibration member includes at least one material selected from the group consisting of metal, resin, glass, wood, rubber, plastic, fiber, cloth, paper, leather, and carbon; 19. The acoustic device of any one of claims 1 to 18, wherein the vibrating member is at least one of a display panel including pixels configured to display an image, a screen panel onto which an image is projected from a display device, a lighting panel, a light emitting diode lighting panel, an organic light emitting lighting panel, an inorganic light emitting lighting panel, a signage panel, an interior material of a vehicle, a glass window of a vehicle, an exterior material of a vehicle, a seat interior material of a vehicle, a ceiling material of a vehicle, a ceiling material of a building, an interior material of a building, a glass window of a building, an interior material of an aircraft, a glass window of an aircraft, and a mirror.

20. the vibration member is a display panel of a display device, the display panel includes an image display surface on which an image is displayed and a back surface opposed to the image display surface; The acoustic device according to claim 1 , wherein vibrations generated by the first vibration element, the second vibration element, and the third vibration element are transmitted to the rear surface of the display panel.

Images