Quasi-adiabatic thermoacoustic device and electronic equipment

Abstract

The invention belongs to the technical field of sound production devices, and discloses a quasi-adiabatic thermotropic sound production device and electronic equipment. The thermoacoustic device realizes sound production based on a thermoacoustic effect, a sound production frequency band covers an audible sound frequency band and an ultrasonic frequency band of human ears, and the thermoacoustic device comprises a signal excitation device and a thermoacoustic element; the thermotropic sound-making element comprises a first sound-making film, a substrate structure and a second sound-making film, the first sound-making film and the second sound-making film have the same electrothermal response capability, and the electrothermal response capability is the capability of generating thermal oscillation after the sound-making film is stimulated by an excitation signal; the signal excitation device applies the same excitation current to the first sound production film and the second sound production film of the thermotropic sound production element through the wire, so that the first sound production film and the second sound production film generate the same thermal oscillation. The construction of the quasi-thermal insulation structure reduces the heat transfer from the first and second sound production films on the two sides to the middle substrate structure, so that the heat-work conversion efficiency of the thermotropic sound production device is effectively improved.

Description

Technical Field

[0001] The present application relates to the technical field of sound-generating devices, and in particular to a quasi-adiabatic thermal sound-generating device and electronic equipment. Background Art

[0002] Traditional speakers are divided into several types, such as dynamic, electrostatic, electromagnetic and piezoelectric. However, each traditional speaker has some limitations, such as the relatively narrow frequency response range of dynamic speakers, the low efficiency of electrostatic speakers, the unstable performance of electromagnetic speakers, and the easy distortion of piezoelectric speakers during playback. Compared with these traditional types, thermoacoustic speakers represent an innovative technology. Unlike traditional speakers, they do not require the vibration of the sound-generating material itself to produce sound, so there is no specific resonant frequency, and the spectrum can cover an extremely wide frequency band. Thermoacoustic speakers apply an AC signal at both ends of the sound-generating material and use the Joule effect to make the temperature of the sound-generating material oscillate with a relative frequency. In air or other media, this thermal oscillation causes the air around the thermoacoustic membrane to expand and contract, thereby emitting sound waves of a relative frequency. However, existing thermoacoustic speakers have the problem of low heat-to-work conversion efficiency, and usually require higher power input to achieve a sound pressure level similar to that of traditional speakers. Summary of the invention

[0003] To this end, the embodiments of the present application provide a quasi-adiabatic thermoacoustic device and an electronic device. The thermoacoustic device of the present application improves the heat-to-work conversion efficiency through a quasi-adiabatic thermoacoustic element.

[0004] In a first aspect, the present application provides a quasi-adiabatic thermosound generating device.

[0005] This application is achieved through the following technical solutions:

[0006] A quasi-adiabatic thermoacoustic device, wherein the sound frequency of the thermoacoustic device covers the audible sound frequency band and the ultrasonic frequency band of the human ear, comprising:

[0007] Signal excitation device and thermoacoustic element;

[0008] The thermoacoustic element comprises a base structure, a first acoustic film and a second acoustic film symmetrically arranged on both sides of the base structure, wherein the first acoustic film and the second acoustic film have the same electrothermal response capability, and the electrothermal response capability is the capability of the acoustic film to generate thermal oscillation after being stimulated by an excitation signal;

[0009] The signal excitation device is used to apply the same excitation signal to the first sound-generating film and the second sound-generating film of the thermosound element, so that the first sound-generating film and the second sound-generating film generate the same thermal oscillation.

[0010] In a preferred example of the present application, it can be further configured that the signal excitation device includes: a control circuit module, a power amplification module and a dynamic analysis module;

[0011] The control circuit module is used to adjust the frequency and amplitude of the excitation signal.

[0012] The power amplifier module is used to amplify the excitation signal and transmit the amplified excitation signal to the thermoacoustic element.

[0013] The dynamic analysis module is used to detect and analyze the amplified excitation signal and transmit the analysis result to the power amplification module.

[0014] In a preferred example of the present application, it can be further configured that the signal excitation device is configured as follows:

[0015] By adjusting the parameter setting of the control circuit module, the first excitation current frequency of the excitation signal is set;

[0016] The control circuit module outputs the excitation signal to the power amplification module, and the power amplification module amplifies the excitation signal according to the target sound pressure level and determines the second excitation current frequency of the amplified excitation signal;

[0017] The dynamic analysis module performs analysis based on the first excitation current frequency and the second excitation current frequency, and feeds back the analysis result to the power amplification module, and the analysis result is used by the power amplification module to adjust the amplification strategy.

[0018] In a preferred example of the present application, it can be further configured that the signal excitation device is configured as follows:

[0019] By adjusting the parameter setting of the control circuit module, a first excitation voltage value of the excitation signal is set;

[0020] The control circuit module outputs the excitation signal to the power amplification module, and the power amplification module amplifies the excitation signal according to the target sound pressure level and determines a second excitation voltage value of the amplified excitation signal;

[0021] The dynamic analysis module performs analysis based on the second excitation voltage value and the first excitation voltage value, and feeds back the analysis result to the power amplification module, where the analysis result is used for the power amplification module to adjust the amplification strategy.

[0022] In a preferred example of the present application, it can be further configured that the first sound-emitting film and the second sound-emitting film are connected to the signal excitation device through a wire.

[0023] In a preferred example of the present application, it can be further arranged that the material of the base structure is a polymer material, and the polymer material includes any one of polyimide film, polyvinyl alcohol film, polytetrafluoroethylene film, polyvinyl chloride film, polyethylene film, polypropylene film, polystyrene film, polyester film, polycarbonate film, polyparaxylene film, polyethylene naphthalate film, high-density polyethylene film, silicone rubber film, polyester amide film, polymethyl methacrylate film, polyetheretherketone film, polyamide film, polyetherimide film, and liquid crystal polymer film.

[0024] In a preferred example of the present application, it can be further arranged that the first sound-emitting film and the second sound-emitting film are made of the same material, including any one of gold, platinum, silver, copper, aluminum, molybdenum, tungsten, nickel, zinc, iron, tin and their alloys, induced graphene, carbon nanotubes, graphite, carbon black, carbon fiber, indium tin oxide, stainless steel, gallium indium liquid metal, poly 3,4-ethylenedioxythiophene / polystyrene sulfonate, polypyrrole, polyaniline, polyacetylene, and conductive non-woven fabrics.

[0025] In a preferred example of the present application, it can be further configured that the materials of the first sound-emitting film and the second sound-emitting film are both induced graphene, and the thermo-induced sound-emitting element is prepared by the following steps:

[0026] Lay the base structure flat below the laser emitter of the laser engraving machine so that the laser beam emitted by the laser emitter irradiates the base structure;

[0027] Selecting a first irradiation area on a surface of the substrate structure, irradiating the first irradiation area with a laser of preset power, so that the laser induces the substrate structure of the first irradiation area to be converted into a graphene structure, and a first sound-emitting film is generated on the surface of the substrate structure;

[0028] A second irradiation area is selected on the other surface of the substrate structure, and a laser of preset power is irradiated on the second irradiation area so that the laser induces the conversion of the substrate structure of the second irradiation area into a graphene structure, thereby generating a second sound-emitting film on the surface of the substrate structure, wherein the second irradiation area is symmetrical to the first irradiation area with respect to the substrate structure.

[0029] In a second aspect, the present application provides an electronic device.

[0030] This application is achieved through the following technical solutions:

[0031] An electronic device, wherein a sound generating device of the electronic device comprises the thermoacoustic device as described in the first aspect.

[0032] In a preferred example of the present application, it can be further configured that the electronic device includes a display device, and the thermoacoustic device is arranged in the display device.

[0033] In summary, compared with the prior art, the technical solution provided in the embodiment of the present application has at least the following beneficial effects:

[0034] The signal excitation device and thermo-sound element of the present application; the thermo-sound element comprises a first sounding film, a base structure and a second sounding film, wherein the first sounding film and the second sounding film have the same electrothermal response capability, wherein the electrothermal response capability is the capability of the sounding film to generate thermal oscillations after being stimulated by an excitation signal; the signal excitation device is used to apply the same excitation current to the first sounding film and the second sounding film of the thermo-sound element, so that the first sounding film and the second sounding film generate the same thermal oscillations. The two sounding films of the thermo-sound element of the present application have the same electrothermal response capability, and when voltages of the same amplitude and the same phase are applied to the two sounding films, the same temperature rise will occur on the two sounding films, which can reduce the transfer of heat from the sounding films to the intermediate base structure, thereby improving the efficiency of converting thermal energy into sound energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of the structure of a quasi-adiabatic thermoacoustic device provided in one embodiment of the present application;

[0036] Figure 2 A schematic diagram of the structure of a thermoacoustic element provided in one embodiment of the present application;

[0037] Figure 3 A schematic diagram of the structure of a thermoacoustic element provided in yet another embodiment of the present application;

[0038] Figure 4 The sound pressure level test result of the thermoacoustic device provided in one embodiment of the present application;

[0039] Description of reference numerals:

[0040] Signal excitation device 1, thermoacoustic element 2, first sound-emitting film 201, base structure 200, second sound-emitting film 202, control circuit module 101, dynamic analysis module 102, power amplification module 103. DETAILED DESCRIPTION

[0041] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

[0042] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0043] In addition, the term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application, unless otherwise specified, generally indicates that the associated objects before and after are in an "or" relationship.

[0044] In this application, the terms "first", "second", etc. are used to distinguish identical or similar items with basically the same effects and functions. It should be understood that there is no logical or temporal dependency between "first", "second", and "nth", nor is there any limitation on quantity and execution order.

[0045] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0046] First, the principle of thermoacoustic devices is introduced. Thermoacoustic devices use the thermoacoustic effect to generate sound without mechanical vibration of the sound-generating material. When an AC signal is applied to the conductive medium of the device, it causes periodic Joule heat changes on the surface of the conductive medium, which are then transmitted to the adjacent air, causing air fluctuations. This causes the air to be compressed and expanded periodically, thereby generating sound waves, which then propagate in all directions. Since this sound-generating mechanism does not rely on the mechanical vibration of the sound-generating element, it does not generate resonance peaks in the spectrum, thereby achieving a wide frequency response range.

[0047] The embodiments of the present application are further described in detail below in conjunction with the drawings in the specification.

[0048] like Figure 1 The figure shows a quasi-adiabatic thermoacoustic device provided by the first exemplary embodiment of the present application, the thermoacoustic device comprising:

[0049] A signal excitation device 1 and a thermo-sounding element 2; the thermo-sounding element 2 comprises a base structure 200, and a first sounding film 201 and a second sounding film 202 symmetrically arranged on both sides of the base structure 200, wherein the first sounding film 201 and the second sounding film 202 have the same electrothermal response capability, and the electrothermal response capability is the capability of the sounding film to generate thermal oscillations after being stimulated by an excitation signal, and the electrothermal response capability can also be understood as the temperature rise of the sounding film after being stimulated by an excitation current.

[0050] The signal excitation device 1 applies the same excitation signal to the first sounding film 201 and the second sounding film 202 of the thermosound element 2, so that the first sounding film 201 and the second sounding film 202 produce the same thermal oscillation, that is, the same Joule heat change is generated in the first sounding film 201 and the second sounding film 202.

[0051] Specifically, the first sounding film 201 and the second sounding film 202 are symmetrically arranged on the two surfaces of the base structure 200, and the first sounding film 201, the base structure 200 and the second sounding film 202 form a three-layer structure similar to a "sandwich". The first sounding film 201 and the second sounding film 202 are made of the same thermoacoustic material, and the first sounding film 201 and the second sounding film 202 are the same in area size, thickness and other settings. When the signal excitation device 1 applies the same excitation signal to the first sounding film 201 and the second sounding film 202, the first sounding film 201 and the second sounding film 202 will have the same electrothermal response ability, that is, the first sounding film 201 and the second sounding film 202 on both sides of the base structure 200 will produce the same temperature rise after being stimulated by the same excitation signal. This can reduce the heat transfer from the first sounding film 201 and the second sounding film 202 on both sides to the middle base structure 200, thereby reducing heat loss and slowing down the temperature drop gradient. The quasi-insulating thermoacoustic element formed by the first sounding film 201, the base structure 200 and the second sounding film 202 can effectively improve the heat-to-work conversion efficiency of the thermoacoustic device made using the thermoacoustic element.

[0052] Among them, the first sound-emitting film 201 and the second sound-emitting film 202 are made of the same material, and conductive materials can be used, including but not limited to gold, platinum, silver, copper, aluminum, molybdenum, tungsten, nickel, zinc, iron, tin and alloys of the above metal materials, induced graphene, carbon nanotubes, graphite, carbon black, carbon fiber, indium tin oxide (ITO), stainless steel, gallium indium liquid metal, poly 3,4-ethylenedioxythiophene / polystyrene sulfonate (PEDOT / PSS), polypyrrole, polyaniline, polyacetylene, and any one of conductive non-woven fabrics.

[0053] The base structure 200 is a polymer material, including but not limited to polyimide film, polyvinyl alcohol film, polytetrafluoroethylene film, polyvinyl chloride film, polyethylene film, polypropylene film, polystyrene film, polyester film, polycarbonate film, polyparaxylene film, polyethylene naphthalate film, high-density polyethylene film, silicone rubber film, polyesteramide film, polymethyl methacrylate film, polyetheretherketone film, polyamide film, polyetherimide film, liquid crystal polymer film. The base structure 200 can also be made of some film materials, such as foam plastic film, glass wool film, asbestos film, high silica wool film, perlite film, rock wool film, ceramic fiber film, silica aerogel film, vacuum insulation film.

[0054] Optionally, the thickness of the base structure is 1 μm to 1000 μm. For example, the thickness of the base structure 200 may be 1 μm, 10 μm, 100 μm, or 1000 μm. The above thickness values ​​are only examples and are not intended to limit the thickness of the base structure.

[0055] Preferably, the thickness of the base structure is 10 μm to 150 μm.

[0056] The first sound-emitting film and the second sound-emitting film are connected to the signal excitation device through a wire. It can be understood that the wire is a metal material with good electrical conductivity, such as silver, copper, gold, aluminum or an alloy thereof.

[0057] In a feasible implementation, Figure 2 ( Figure 2 a and Figure 2 As shown in FIG. 2 , two metal wires are arranged on both side edges of the first sound-emitting film 201. The wires are coated with silver paste. One end of the metal wire is led out from the first sound-emitting film 201 and then bypasses the base structure 200 to connect with the second sound-emitting film 202. The metal wires are used to connect the thermoacoustic element 2 and the signal excitation device 1.

[0058] like Figure 3 As shown, in some preferred exemplary embodiments, the signal excitation device 1 includes: a control circuit module 101, a power amplification module 103 and a dynamic analysis module 102; the control circuit module 101 is used to adjust the frequency and amplitude of the excitation signal, the power amplification module 103 is used to amplify the excitation signal, and output the amplified excitation signal to the thermoacoustic element 2; the dynamic analysis module 102 is used to detect and analyze the amplified excitation signal, and transmit the analysis result to the power amplification module 103. The analysis result is used by the power amplification module 103 to adjust the amplification strategy. The excitation signal refers to the original signal used to drive the thermoacoustic element 2 to work, and the signal is an electrical signal containing sound wave information.

[0059] The output end of the control circuit module 101 is connected to the input end of the dynamic analysis module 102 and the input end of the power amplifier module 103 respectively, the output end of the dynamic analysis module 102 is connected to the power amplifier module 103, and the output end of the power amplifier module 103 is connected to the thermoacoustic element 2. The control circuit module 101 controls the frequency and amplitude of the output excitation signal (including AC current and DC current), the power amplifier module 103 amplifies the excitation signal, and the dynamic analysis module 102 analyzes the amplified excitation signal. If the amplified excitation signal can meet the target sound pressure level corresponding to the preset sound wave, the analysis result that meets the requirements is sent to the power amplifier module 103, and the power amplifier module 103 transmits the amplified excitation signal to the thermoacoustic element 2. If the dynamic analysis module 102 analyzes the amplified excitation signal and confirms that the amplified excitation signal does not meet the target sound pressure level corresponding to the preset sound wave, the analysis result that does not meet the requirements is sent to the power amplifier module 103, and the power amplifier module 103 adjusts the amplification strategy until the amplified excitation signal meets the preset target sound pressure level. The dynamic analysis module adopts a dynamic analyzer, and the power amplification module adopts a power amplifier.

[0060] In some preferred embodiments, the output end of the power amplifier module 103 is connected to the thermoacoustic element 2 via a wire. The wire has excellent electrical conductivity, and the use of the wire to connect the power amplifier module 103 and the thermoacoustic element 2 can reduce the loss of electrical signals during transmission and improve the electrical-thermal-acoustic conversion efficiency of the entire thermoacoustic device.

[0061] In one embodiment, the first excitation current frequency of the excitation signal output by the control circuit module 101 is set by changing the parameter setting in the control circuit module 101; the control circuit module 101 outputs the excitation signal to the power amplifier module 103, and the power amplifier module 103 amplifies the excitation signal according to the target sound pressure level and determines the second excitation current frequency of the amplified excitation signal; the dynamic analysis module 102 receives the amplified excitation signal and the second excitation current frequency from the power amplifier module 103 and the first excitation current frequency of the excitation signal from the control circuit module 101, analyzes the second excitation current frequency and the first excitation current frequency, determines the adjustment of the excitation current frequency, and determines whether the adjusted excitation current frequency reaches the target frequency required by the preset sound pressure level. If the preset target frequency is not reached, the amplification strategy of the power amplifier module 103 is adjusted again until the target frequency is reached. After ensuring that the adjusted second excitation current frequency reaches the preset target frequency, the adjusted excitation signal is transmitted to the thermoacoustic element 2, thereby changing the frequency of the sound emitted by the thermoacoustic element 2.

[0062] In another embodiment, the first excitation voltage value of the excitation signal is set by adjusting the parameter setting of the control circuit module 101; the control circuit module 101 outputs the excitation signal to the power amplifier module 103, the power amplifier module 103 amplifies the excitation signal according to the target sound pressure level, and determines the second excitation voltage value of the amplified excitation signal; the dynamic analysis module 102 performs analysis and processing based on the second excitation voltage value and the first excitation voltage value, and feeds back the analysis result to the power amplifier module 103, and the analysis result is used for the power amplifier module 103 to adjust the amplification strategy. If the preset target voltage value is not reached, the amplification strategy of the power amplifier module 103 is adjusted again until the target voltage value is reached. After ensuring that the adjusted second excitation voltage value of the excitation signal reaches the preset target voltage value, the amplified excitation signal is transmitted to the thermoacoustic element, thereby changing the sound pressure of the sound emitted by the thermoacoustic element.

[0063] The present application achieves this by integrating the control circuit module, the dynamic analysis module and the power amplification module in the signal excitation device, so that the excitation signal output to the thermoacoustic element has sufficient electrical power, thereby ensuring that the thermoacoustic element can be driven to achieve the required sound pressure level and frequency response, thereby significantly improving the heat-to-work conversion efficiency and sound pressure level of the existing thermoacoustic source.

[0064] In some preferred exemplary embodiments, the first sound-emitting film 201 and the second sound-emitting film 202 of the thermoacoustic element are laser-induced graphene, wherein the preparation process of laser-induced graphene (LIG) is:

[0065] Lay the base structure (polymer structure) and a flat plate for fixing the base structure together directly under the laser emitter of the laser engraving machine so that the laser beam emitted by the laser emitter irradiates the base structure;

[0066] Selecting a first irradiation area on a surface of the base structure, irradiating the first irradiation area with a laser of preset power, so that the laser induces the base structure in the first irradiation area into LIG, and generates a first sound-emitting thin film on the surface of the base structure;

[0067] A second irradiation area is selected on the other surface of the substrate structure, and a laser of preset power is irradiated on the second irradiation area, so that the laser induces the substrate structure of the second irradiation area into LIG, and a second sound-generating film is generated on the surface of the substrate structure. The second irradiation area and the first irradiation area are symmetrically arranged, and the area and shape of the second irradiation area are the same as those of the first irradiation area. Finally, a three-layer structure of LIG-PI-LIG is formed, and a quasi-insulating double-sided thermoacoustic element is prepared.

[0068] Low-resistance metal wires are placed at both ends of LIG and coated with silver paste. The metal wires become electrodes connecting the sound-generating film and the signal excitation device. The laser graphene structure has extremely high thermal conductivity and small heat capacity, which can quickly transfer heat to the surrounding air, thereby effectively improving the sound power and efficiency.

[0069] The quasi-insulated double-sided LIG structure was tested, such as Figure 4 The experimental results show that the thermoacoustic device using the quasi-adiabatic double-sided LIG structure of the present application greatly improves the heat-to-work conversion efficiency and the sound pressure level. Compared with the thermoacoustic device using the single-sided LIG structure, the sound pressure level of the thermoacoustic device using the quasi-adiabatic double-sided LIG structure of the present application is increased by 8dB, which means that the sound pressure level is increased by three times.

[0070] In an optional embodiment, a thermoacoustic element can also be prepared by a double-sided indium tin oxide (ITO) sound-emitting film. The structure of the ITO sound-emitting film is an ITO-glass-ITO structure. Wires are placed at both ends of the ITO and coated with a conductive paste to form electrodes connecting the sound-emitting film and the signal excitation source device. The double-sided ITO sound-emitting element can be integrated into the mobile phone screen, or it can be directly used as the material of the mobile phone screen. By changing the current frequency of the excitation signal, the frequency of the sound wave emitted by the double-sided ITO thermoacoustic speaker can be changed; by changing the voltage of the excitation signal, the sound pressure of the sound emitted by the double-sided ITO thermoacoustic speaker can be changed.

[0071] Another embodiment of the present application further provides an electronic device, which includes the above-mentioned thermoacoustic device. The electronic device can be a mobile phone, tablet, computer, camera, or other electronic device that requires a sound device.

[0072] In some preferred embodiments, the electronic device comprises a display device, and the thermoacoustic device is disposed in the display device.

[0073] The specific limitations of the electronic device provided in this embodiment can be found in the embodiment of the quasi-adiabatic thermoacoustic device described above, and will not be elaborated here.

[0074] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the system described in the present application is divided into different functional units or modules to complete all or part of the functions described above.

Claims

1. A quasi-adiabatic thermoacoustic device, characterized in that: The sound frequency of the thermoacoustic device covers the audible sound frequency band and the ultrasonic frequency band of the human ear, including: Signal excitation device and thermoacoustic element; The thermoacoustic element comprises a base structure, a first acoustic film and a second acoustic film symmetrically arranged on both sides of the base structure, wherein the first acoustic film and the second acoustic film have the same electrothermal response capability, and the electrothermal response capability is the capability of the acoustic film to generate thermal oscillation after being stimulated by an excitation signal; The signal excitation device is used to apply the same excitation signal to the first sound-generating film and the second sound-generating film of the thermosound element, so that the first sound-generating film and the second sound-generating film generate the same thermal oscillation.

2. The quasi-adiabatic thermoacoustic device according to claim 1, characterized in that: The signal excitation device comprises: a control circuit module, a power amplification module and a dynamic analysis module; The control circuit module is used to adjust the frequency and amplitude of the excitation signal. The power amplifier module is used to amplify the excitation signal and transmit the amplified excitation signal to the thermoacoustic element. The dynamic analysis module is used to detect and analyze the amplified excitation signal and transmit the analysis result to the power amplification module.

3. The quasi-adiabatic thermoacoustic device according to claim 2, characterized in that: The signal excitation device is configured as follows: By adjusting the parameter setting of the control circuit module, the first excitation current frequency of the excitation signal is set; The control circuit module outputs the excitation signal to the power amplification module, and the power amplification module amplifies the excitation signal according to the target sound pressure level and determines the second excitation current frequency of the amplified excitation signal; The dynamic analysis module performs analysis based on the first excitation current frequency and the second excitation current frequency, and feeds back the analysis result to the power amplification module, and the analysis result is used by the power amplification module to adjust the amplification strategy.

4. The quasi-adiabatic thermoacoustic device according to claim 2, characterized in that: The signal excitation device is configured as follows: By adjusting the parameter setting of the control circuit module, a first excitation voltage value of the excitation signal is set; The control circuit module outputs the excitation signal to the power amplification module, and the power amplification module amplifies the excitation signal according to the target sound pressure level and determines a second excitation voltage value of the amplified excitation signal; The dynamic analysis module performs analysis based on the second excitation voltage value and the first excitation voltage value, and feeds back the analysis result to the power amplification module, where the analysis result is used for the power amplification module to adjust the amplification strategy.

5. The quasi-adiabatic thermoacoustic device according to any one of claims 1 to 4, characterized in that: The first sound-emitting film and the second sound-emitting film are connected to a signal excitation device through a wire.

6. The quasi-adiabatic thermoacoustic device according to claim 1, characterized in that: The material of the base structure is a polymer material, and the polymer material includes any one of polyimide film, polyvinyl alcohol film, polytetrafluoroethylene film, polyvinyl chloride film, polyethylene film, polypropylene film, polystyrene film, polyester film, polycarbonate film, polyparaxylene film, polyethylene naphthalate film, high-density polyethylene film, silicone rubber film, polyesteramide film, polymethyl methacrylate film, polyetheretherketone film, polyamide film, polyetherimide film, and liquid crystal polymer film.

7. The quasi-adiabatic thermoacoustic device according to claim 6, characterized in that: The first sound-emitting film and the second sound-emitting film are made of the same material, including any one of gold, platinum, silver, copper, aluminum, molybdenum, tungsten, nickel, zinc, iron, tin and their alloys, induced graphene, carbon nanotubes, graphite, carbon black, carbon fiber, indium tin oxide, stainless steel, gallium indium liquid metal, poly 3,4-ethylenedioxythiophene / polystyrene sulfonate, polypyrrole, polyaniline, polyacetylene, and conductive non-woven fabrics.

8. The quasi-adiabatic thermoacoustic device according to claim 7, characterized in that: The materials of the first sound-emitting film and the second sound-emitting film are both induced graphene, and the thermo-induced sound-emitting element is prepared by the following steps: Lay the base structure flat below the laser emitter of the laser engraving machine so that the laser beam emitted by the laser emitter irradiates the base structure; Selecting a first irradiation area on a surface of the substrate structure, irradiating the first irradiation area with a laser of preset power, so that the laser induces the substrate structure of the first irradiation area to be converted into a graphene structure, and a first sound-emitting film is generated on the surface of the substrate structure; A second irradiation area is selected on the other surface of the substrate structure, and a laser of preset power is irradiated on the second irradiation area so that the laser induces the conversion of the substrate structure of the second irradiation area into a graphene structure, thereby generating a second sound-emitting film on the surface of the substrate structure, wherein the second irradiation area is symmetrical to the first irradiation area with respect to the substrate structure.

9. An electronic device, characterized in that: The sound generating device of the electronic device comprises the thermal sound generating device as claimed in any one of claims 1 to 8.

10. The electronic device according to claim 9, characterized in that: The electronic device comprises a display device, and the thermoacoustic device is arranged in the display device.

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