CN102026079B - Sound-producing device - Google Patents

Abstract

The present invention relates to a kind of sound-producing device, comprising: a sounding module, this sounding module includes at least one first electrode, at least one second electrode and a hot sounding film, this first electrode and the second electrode electrically connect with this hot sounding film spaced reciprocally, wherein, described hot sounding film includes a carbon nano tube structure, described sound-producing device farther includes one first protection structure, one second protection structure and an infrared reflection film, described hot sounding film is arranged between this first protection structure and the second protection structure, described infrared reflection film is arranged on the first protection body structure surface.

Description

Sound device

technical field

The invention relates to a sound generating device, in particular to a sound generating device based on the principle of thermoacoustics.

Background technique

As early as the beginning of the 20th century, H.D.Arnold et al. proposed a thermoacoustic effect-based thermosound generator, please refer to the document "Thethermophone as a precision source of sound", H.D.Arnold, I.B.Crandall, Phys.Rev.10, 22-38 (1917) and "On Some Thermal Effects of Electric Currents", William Henry Preece, Proceedings of the Royal Society of London, Vol. 30, pp 408-411 (1879-1881). The thermosounder realizes sound generation by feeding alternating current into a conductor. The conductor must have a small heat capacity, a relatively thin thickness, and can quickly transfer the heat generated inside it to the surrounding gas medium. When alternating current passes through the conductor, the temperature of the conductor can rise and fall rapidly as the intensity of the alternating current changes, and heat exchange occurs rapidly with the surrounding gas medium. The molecules of the surrounding gas medium move, and the density of the gas medium changes accordingly, thereby emitting sound waves. In the prior art, the most effective conductors are metals.

HD Arnold and IBCrandall introduced a simple thermal sounder in the document "Thethermophone as a precision source of sound", Phys.Rev.10, pp22-38 (1917), which uses a platinum sheet as the sounding element, and the thickness of the platinum sheet is 0.7 microns . Please refer to FIG. 1 , the sound emitting element 102 is fixed by a clamp 104 . The sound emitting element 102 and the fixture 104 are disposed on a surface of a substrate 108 . A current lead 106 is electrically connected to the sound generating element 102 for inputting electrical signals to the sound emitting element 102 . Since the sounding frequency of the sounding element 102 is closely related to its heat capacity per unit area. If the heat capacity per unit area is large, the sounding frequency range will be narrow and the intensity will be low; if the heat capacity per unit area is small, the sounding frequency range will be wide and the intensity will be high. In order to obtain sound waves with a wider range of sounding frequency and higher intensity, it is required that the heat capacity per unit area of the sounding element 102 be as small as possible. The metal platinum sheet with a small heat capacity is limited by the material itself, and its thickness can only reach a minimum of 0.7 microns, and the heat capacity per unit area of a platinum sheet with a thickness of 0.7 microns is 2×10 ^-4 joules per square centimeter Kelvin. Limited by the heat capacity per unit area of the material, the sounding frequency of the sounder using the platinum sheet as the sounding element 102 can only reach up to 4 kHz and the sounding intensity is low. Therefore, the above-mentioned thermosounders utilizing the thermoacoustic effect cannot satisfy daily applications.

Contents of the invention

In view of this, it is indeed necessary to provide a sounding device, which has a wider frequency range, higher sounding intensity and better sounding effect.

A sounding device, comprising: a sounding module, the sounding module includes at least one first electrode, at least one second electrode and a thermal sounding film, the first electrode and the second electrode are separated from the thermal sounding film The film is electrically connected, wherein, the thermal sound film includes a carbon nanotube structure, and the sound generating device further includes a first protective structure, a second protective structure and an infrared reflection film, and the thermal sound film is arranged on the first Between the first protection structure and the second protection structure, the infrared reflection film is arranged on the surface of the first protection structure.

A sounding device comprising: at least one first electrode, at least one second electrode and a thermal sounding film, the first electrode and the second electrode are electrically connected to the thermal sounding film at intervals, wherein the thermal sounding The film includes a carbon nanotube structure, and the sound generating device further includes an infrared reflective film and an infrared transmissive film, and the thermal sound film is arranged between the infrared reflective film and the infrared transmissive film.

Compared with the prior art, the sounding device provided by the present invention adopts a carbon nanotube structure as a thermal sounding membrane, and the carbon nanotube structure has a smaller heat capacity per unit area, and the sounding frequency range of the sounding device is wider, and the sounding intensity Higher and better sound.

Description of drawings

Fig. 1 is a structural schematic diagram of a sound generating device using a carbon nanotube film as a thermal sound emitting film in the prior art.

Fig. 2 is a three-dimensional exploded schematic diagram of the sound generating device provided by the first embodiment of the present invention.

Fig. 3 is a scanning electron micrograph of a carbon nanotube stretched film used as a thermosound film according to the first embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a sound generating module using multiple electrodes according to the first embodiment of the present invention.

Fig. 5 is a three-dimensional exploded schematic diagram of the sound generating device provided by the second embodiment of the present invention.

Fig. 6 is a three-dimensional exploded schematic diagram of the sound generating device provided by the third embodiment of the present invention.

detailed description

The sound generating device of the embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

Please refer to FIG. 2 , the first embodiment of the present invention provides a sound generating device 10 , the sound generating device 10 includes a sound generating module 110 , a first protection structure 120 , a second protection structure 130 and an infrared reflection film 140 . The first protection structure 120 and the second protection structure 130 are respectively arranged on two sides of the sound module 110 . The infrared reflection film 140 is disposed on the surface of the first protection structure 120 .

The acoustic module 110 includes a thermal acoustic film 112 , at least one first electrode 114 and at least one second electrode 116 . The first electrode 114 and the second electrode 116 are electrically connected to the thermoacoustic film 112 at intervals from each other. Specifically, the first electrode 114 and the second electrode 116 are arranged at intervals, and the thermosound film 112 may be arranged between the first electrode 114 and the second electrode 116 . The thermal sound-generating membrane 112 receives signals input from the first electrode 114 and the second electrode 116 to emit sound waves.

The thermoacoustic membrane 112 is disposed between the first protection structure 120 and the second protection structure 130 . The thermoacoustic membrane 112 may include a carbon nanotube structure. The carbon nanotube structure includes a plurality of carbon nanotubes. The carbon nanotube structure is a self-supporting structure. The so-called self-supporting structure means that multiple carbon nanotubes in the carbon nanotube structure attract each other through van der Waals force, so that the carbon nanotube structure has a specific shape, which can be suspended in the air and still maintain its specific shape. In this embodiment, the thermosonic film 112 is at least partially suspended between the first protection structure 120 and the second protection structure 130 . Specifically, the thermosonic film 112 may be partially suspended between the first protection structure 120 and the second protection structure 130 through the first electrode 114 and the second electrode 116 . The carbon nanotube structure is layered and has a large specific surface area. The carbon nanotube structure has a thickness of 0.5 nanometers to 1 millimeter. Preferably, the carbon nanotube structure has a thickness of 50 nanometers. The heat capacity per unit area of the carbon nanotube structure may be less than 2×10 ⁻⁴ joules per square centimeter Kelvin. Preferably, the heat capacity per unit area of the carbon nanotube structure may be greater than or equal to 1.7×10 ^-6 Joule per square centimeter Kelvin and less than or equal to 1.7×10 ^-5 Joule per square centimeter Kelvin. In this embodiment, the heat capacity per unit area of the carbon nanotube structure is 1.7×10 ⁻⁶ joules per square centimeter Kelvin. The carbon nanotubes in the carbon nanotube structure include one or more of single-wall carbon nanotubes, double-wall carbon nanotubes and multi-wall carbon nanotubes. The single-walled carbon nanotubes have a diameter of 0.5 nm to 50 nm, the double-walled carbon nanotubes have a diameter of 1.0 nm to 50 nm, and the multi-walled carbon nanotubes have a diameter of 1.5 nm to 50 nm.

The carbon nanotube structure may include at least one carbon nanotube film. Specifically, the carbon nanotube structure may include a plurality of carbon nanotube films laid in parallel and without gaps or/and stacked. The carbon nanotube film includes a plurality of uniformly distributed carbon nanotubes, and the carbon nanotubes are closely combined by van der Waals force. The carbon nanotubes in the carbon nanotube film can be ordered or disordered. The so-called ordered arrangement means that the arrangement direction of the carbon nanotubes is regular. The so-called disordered arrangement means that the arrangement direction of the carbon nanotubes is irregular. Specifically, when the carbon nanotube structure includes disorderly arranged carbon nanotubes, the carbon nanotubes are intertwined or the carbon nanotube structure is isotropic; when the carbon nanotube structure includes ordered arranged carbon nanotubes, the carbon nanotubes are The nanotubes are preferentially oriented in one direction, or the carbon nanotube structure includes multiple parts, the carbon nanotubes are preferentially oriented in one direction in each part, and the carbon nanotubes in two adjacent parts can be arranged in different directions. Specifically, the carbon nanotube film includes one or more of carbon nanotube drawn film, carbon nanotube rolled film, and carbon nanotube flocculated film.

The carbon nanotube drawn film includes a plurality of carbon nanotubes that are substantially parallel to each other and arranged substantially parallel to the surface of the carbon nanotube drawn film. Specifically, the carbon nanotube drawn film includes a plurality of carbon nanotubes connected end-to-end by van der Waals force and arranged in a preferred orientation basically along the same direction. The carbon nanotube drawn film can be obtained by directly pulling from the carbon nanotube array, and is a self-supporting structure. The thickness of the drawn carbon nanotube film can be 0.5 nanometers to 100 microns, and the width is related to the size of the carbon nanotube array from which the drawn carbon nanotube film is drawn, and the length is not limited. Please refer to FIG. 3 for the scanning electron microscope photo of the carbon nanotube drawn film. Specifically, each carbon nanotube film includes a plurality of continuous and aligned carbon nanotube segments. The plurality of carbon nanotube segments are connected end to end by van der Waals force. Each carbon nanotube segment includes a plurality of parallel carbon nanotubes, and the plurality of parallel carbon nanotubes are closely combined by van der Waals force. It can be understood that carbon nanotube structures with different areas and thicknesses can be prepared by laying multiple carbon nanotube films in parallel without gaps or/and in layers. When the carbon nanotube structure includes a plurality of stacked carbon nanotube drawn films, the arrangement direction of the carbon nanotubes in adjacent carbon nanotube drawn films forms an included angle α, and α is greater than or equal to 0 degrees and less than or equal to 90 degrees (0°≤α≤90°). Compared with single-layer carbon nanotube stretched films, multi-layered carbon nanotube drawn films, especially multi-layered carbon nanotube drawn films arranged crosswise, are beneficial to improve the strength of the thermal sound-emitting film 112 . For the structure and preparation method of the carbon nanotube stretched film, please refer to the Chinese published patent application No. 101239712A filed by Fan Shoushan et al. on February 9, 2007 and published on August 13, 2008.

The carbon nanotube laminated film includes uniformly distributed carbon nanotubes. The carbon nanotube laminated film can be isotropic or include multiple parts, the carbon nanotubes are arranged in a preferred orientation along one direction in each part, and the carbon nanotubes in two adjacent parts can be arranged in different directions or aligned in the same direction. The carbon nanotubes in the carbon nanotube rolled film overlap each other. The carbon nanotube rolled film can be obtained by rolling a carbon nanotube array. The carbon nanotube array is formed on the surface of a substrate, and the carbon nanotubes in the prepared carbon nanotube rolling film form an angle β with the surface of the substrate of the carbon nanotube array, wherein β is greater than or equal to 0 degrees and less than or equal to 15 degrees (0≤β≤15°). The carbon nanotube rolling film is a self-supporting structure, which can be self-supporting without substrate support. For the carbon nanotube rolled film and its preparation method, please refer to the Chinese published patent application No. 101284662 filed by Fan Shoushan et al. on June 1, 2007 and published on October 15, 2008. The carbon nanotube flocculated film includes intertwined and evenly distributed carbon nanotubes, and the length of the carbon nanotubes can be greater than 10 centimeters. The carbon nanotubes attract and entangle with each other through van der Waals force to form a network structure. The carbon nanotube flocculation film is isotropic. The carbon nanotubes in the carbon nanotube flocculation film are evenly distributed and randomly arranged to form a large number of microporous structures, and the diameter of the micropores is 1 nanometer to 10 micrometers. For the carbon nanotube flocculated film and its preparation method, please refer to the Chinese published patent application No. 101314464 filed by Fan Shoushan et al. on April 13, 2007 and published on December 3, 2008.

The first electrode 114 and the second electrode 116 are formed of conductive material, and their shape can be rod or strip. Specifically, the materials of the first electrode 114 and the second electrode 116 can be selected from metal, metallic carbon nanotubes and the like. Wherein, the metal includes stainless steel, tungsten, copper, molybdenum or silver and the like. In the embodiment of the present invention, the first electrode 114 and the second electrode 116 are strip-shaped metal electrodes, and the strip-shaped metal electrodes may have a self-supporting structure. The first electrode 114 and the second electrode 116 can be used to support the thermal acoustic film 112 and input signals to the thermal acoustic film 112 . The input signal includes an alternating current signal or an audio electric signal and the like. Since the first electrode 114 and the second electrode 116 are arranged at intervals, when the thermal sound-generating film 112 is applied to the sound-generating device 10 , a certain resistance value can be connected to avoid short-circuit phenomenon.

It can be understood that the sound generating device 10 may further include a plurality of first electrodes 114 and a plurality of second electrodes 116 . Please refer to FIG. 4, the plurality of first electrodes 114 and the plurality of second electrodes 116 are alternately arranged at intervals, that is, there is a second electrode 116 between any two adjacent first electrodes 114, and any two adjacent There is a first electrode 114 between the second electrodes 116 . Preferably, the distances between the plurality of first electrodes 114 and the plurality of second electrodes 116 are equal. Further, the plurality of first electrodes 114 may be electrically connected, and the plurality of second electrodes 116 may be electrically connected. Specifically, the plurality of first electrodes 114 may be electrically connected through wires and then used as a signal input end, and the plurality of second electrodes 116 may be electrically connected through wires and then used as another signal input end. When in use, electrical signals can be input to the thermal sound-emitting membrane 112 through the above two signal input terminals. The above-mentioned connection method can realize the parallel connection of the thermal sound-emitting films 112 between adjacent electrodes. The resistance of the thermo-sounding films 112 connected in parallel is smaller than the resistance of the thermo-sounding films 112 before the parallel connection, which can reduce the working voltage.

In this embodiment, the carbon nanotube structure as the thermal sound-emitting film 112 includes a layer of carbon nanotube drawn film. The carbon nanotubes are preferentially aligned along the same direction in the carbon nanotube structure. The sound generating device 10 includes a first electrode 114 and a second electrode 116 . The carbon nanotubes are preferentially aligned along the direction from the first electrode 114 to the second electrode 116 . The carbon nanotube structure has a thickness of 50 nanometers. Since carbon nanotubes have a large specific surface area, under the action of van der Waals force, the carbon nanotube structure itself has good adhesion, so when the carbon nanotube structure is used as the thermal sound-emitting membrane 112, the first The electrodes 114 and the second electrodes 116 can be directly adhered and fixed to the thermal sound-generating film 112 to form good electrical contact.

The first protection structure 120 and the second protection structure 130 can be used to protect the sound module 110 . The first protection structure 120 and the second protection structure 130 may be layered or plate-shaped. They are respectively arranged on two sides of the sound-generating module 110 , wherein the first protection structure 120 is arranged on the side of the sound-generating device 10 facing the user. The materials of the first protection structure 120 and the second protection structure 130 are not limited, as long as they have good heat resistance. Preferably, the first protection structure 120 and the second protection structure 130 have relatively high sound transmittance. The shapes of the first protection structure 120 and the second protection structure 130 are not limited, and may be a plane or a curved surface. The material of the first protection structure 120 and the second protection structure 130 can be selected to be a conductive material, such as metal, or an insulating material, such as plastic, plastic and the like. The metal includes one or more of stainless steel, carbon steel, copper, nickel, titanium, zinc and aluminum. The first protection structure 120 and the second protection structure 130 can be a porous structure, such as a grid, or a non-porous structure, such as a glass plate, a quartz plate, and the like. When the glass plate or quartz plate is used as the second protective structure 130, the glass plate or quartz plate should have better infrared transmission performance. In addition, when the glass plate or quartz plate is used as the second protective structure 130, the first electrode 114 and the second electrode 116 can be directly formed on the surface of the second protective structure 130, at this time, the thermal sound-emitting film 112 can be suspended between the first electrode 114 and the second electrode 116 .

In the embodiment of the present invention, both the first protection structure 120 and the second protection structure 130 are porous structures. Specifically, both the first protection structure 120 and the second protection structure 130 are a plastic grid, and the plastic grid has a plurality of through holes. The percentages of the total through hole areas of the first protection structure 120 and the second protection structure 130 to the areas of the first protection structure 120 and the second protection structure 130 respectively may be greater than 0% and less than 100%. Preferably, the The total area of the through holes in the first protection structure 120 and the second protection structure 130 accounts for 20% to 99% of the area of the first protection structure 120 and the second protection structure 130 respectively. The distribution and shape of the plurality of through holes are not limited.

The infrared reflective film 140 is spaced apart from the thermal sound film 112 . The infrared reflective film 140 may be disposed on the outer surface or the inner surface of the first protection structure 120 . The infrared reflective film 140 has better infrared reflective properties, and can change the propagation direction of the infrared rays radiated from the thermosonic film 112 . The infrared reflective film 140 can be used to reflect the infrared rays (including near-infrared rays and far-infrared rays) radiated toward the user by the thermal sound-emitting film 112 to the other side of the thermal-sound-emitting film 140 (ie, the side away from the user). Preferably, the infrared reflective film 140 also has better heat insulation effect. The material of the infrared reflective film 140 is not limited, as long as it has a high infrared reflectivity. The infrared reflectivity of the infrared reflective film 140 may be greater than or equal to 20% and less than or equal to 100%. Preferably, the infrared reflectivity of the infrared reflective film 140 is greater than or equal to 70% and less than or equal to 99%. In this embodiment, the infrared reflectivity of the infrared reflective film 140 is 95%. The infrared reflective film 140 may include a substrate and a reflective film disposed on the surface of the substrate. The reflective film is a metal reflective film. The metal includes materials with better infrared reflection properties such as gold, silver or copper. The substrate comprises a polymer or a fabric. The polymers include polyester films and the like. The metal reflective film can be prepared by sputtering a layer of metal material with high infrared reflectivity on the surface of the substrate. In addition, at least one dielectric film may be further provided on the surface of the metal reflective film away from the substrate, and the material of the dielectric film may include silicon oxide, magnesium fluoride, silicon dioxide, or aluminum oxide. The dielectric film can be used to protect the metal reflective film. The infrared reflective film 140 can be made of transparent materials, or made of opaque materials. Preferably, the infrared reflective film 140 is made of transparent materials. In this embodiment, the infrared reflective film 140 is a transparent polyester film with a silver film on the surface, and the infrared reflective film 140 is provided on the outer surface of the first protective structure 120 . When the first protection structure 120 is a non-porous structure, the infrared reflection film 140 may only include a metal reflection film, and the metal reflection film may also be directly formed on the surface of the first protection structure 120 .

The distance between the infrared reflective film 140 and the thermal sound film 112 is not limited. Preferably, the infrared reflective film 140 does not affect the heat exchange between the thermal sound film 112 and the surrounding medium, and can effectively reflect infrared rays to the rear side of the sound generating device 10 . In this embodiment, the distance between the infrared reflective film 140 and the thermosound film 112 is about 10 millimeters.

When the above-mentioned sounding device 10 is in use, since the carbon nanotube structure is composed of uniformly distributed carbon nanotubes, and the carbon nanotube structure is layered and has a larger specific surface area, the carbon nanotube structure has a smaller unit Area heat capacity and large heat dissipation surface, after the input signal, the carbon nanotube structure can rapidly rise and fall in temperature, resulting in periodic temperature changes, and rapid heat exchange with the surrounding medium, so that the density of the surrounding medium changes periodically , and then make a sound. The sounding principle of the thermal sounding membrane 112 is the conversion of "electricity-heat-acoustic". When the sound generating device 10 is in use, the thermal sound emitting film 112 radiates heat to the surroundings in the form of electromagnetic waves and rapidly exchanges heat with the surrounding medium. In the present invention, an infrared reflective film 140 is arranged on the surface of the first protective structure 120 on the side of the sound generating device 10 facing the user to control the propagation direction of the infrared rays radiated from the thermal sound emitting film 112, and the thermal sound emitting film 112 is directed toward the The infrared rays radiated from one side of the user are reflected to the other side of the heat-sounding film 112 , so that the user on the side of the infrared reflective film 140 will not feel the heat.

The sound pressure level of the sound generating device 10 provided by the embodiment of the present invention is greater than 50 decibels per watt, and the sound frequency range is from 1 Hz to 100,000 Hz (ie, 1 Hz-100 kHz). The distortion degree of the sound generating device in the frequency range of 500 Hz to 40,000 Hz can be less than 3%. When a single-layer carbon nanofilm of A4 paper size is used as the thermal sounding film 112, a microphone is arranged at a position 5 centimeters away from the thermal sounding film, and when the input voltage is 50 volts, the measured sounding device 10 The sound frequency is greater than or equal to 100 Hz and less than or equal to 100,000 Hz, and the sound intensity is greater than 50 decibels per watt. The sounding device 10 has a wide range of sounding frequency, high intensity and good sounding effect.

Please refer to Fig. 5, the second embodiment of the present invention provides a sounding device 20, the sounding device 20 includes a sounding module 210, a first protection structure 220, a second protection structure 230, an infrared reflective film 240 and an Infrared transmissive film 250 . The acoustic module 210 includes a thermal acoustic film 212 , at least one first electrode 214 and at least one second electrode 216 . The first protection structure 220 and the second protection structure 230 are respectively disposed on two sides of the sound module 210 . The infrared reflection film 240 is disposed on the surface of the first protection structure 220 . The infrared transmissive film 250 is disposed on the surface of the second protection structure 230 .

The structure of the sound generating device 20 provided in the second embodiment of the present invention is basically the same as that of the sound generating device 10 in the first embodiment. The difference is that the sound emitting device 20 provided by the second embodiment of the present invention further includes an infrared transmissive film 250 disposed on the surface of the second protective structure 230 . The infrared transmissive film 250 is beneficial to improve the infrared transmittance of the sound generating device 20 on the side of the second protection structure 230 . In addition, when the second protective structure 230 adopts a porous structure, such as a grid, the infrared transmissive film 250 can further protect the thermosonic film 212 . The material of the infrared transmissive film 250 may be an existing material with relatively high infrared transmittance. The infrared transmittance of the infrared transmissive film 250 may be greater than or equal to 10% and less than or equal to 99%. Preferably, the infrared transmittance of the infrared transmissive film 250 may be greater than or equal to 60% and less than or equal to 99%. In this embodiment, the infrared transmittance of the infrared transmissive film 250 is 90%. The material of the infrared transmissive film 250 includes zinc sulfide, zinc selenide, diamond, diamond-like carbon and other materials with high infrared transmittance in the infrared band.

Referring to FIG. 6 , the third embodiment of the present invention provides a sound generating device 30 , which includes a sound generating module 310 , an infrared reflective film 340 and an infrared transmissive film 350 . The infrared reflective film 340 and the infrared transmissive film 350 are respectively arranged on two sides of the sound emitting module 210 and fixed to the sound emitting module 310 . The acoustic module 310 includes a thermal acoustic film 312 , a first electrode 314 , a second electrode 316 and a supporting structure 318 . The thermoacoustic film 312 is disposed between the infrared reflective film 340 and the infrared transmissive film 350 .

The structure of the sound generating device 30 provided in the third embodiment is basically the same as that of the sound generating device 10 in the first embodiment. The difference is that the sound generating device 30 provided by the third embodiment of the present invention only includes a sound generating module 310 , an infrared reflective film 340 and an infrared transmissive film 350 , and the sound generating module 310 further includes a supporting structure 318 . The sound emitting device 30 does not include the first protection structure and the second protection structure. The infrared reflective film 340 and the infrared transmissive film 350 can further protect the thermosonic film 312 . The support structure 318 is made of insulating material, such as glass, ceramic, resin, wood material, quartz, or plastic. The supporting structure 318 may include four side panels (not shown) connected end to end, namely a first side panel, a second side panel, a third side panel and a fourth side panel. The first side panel, the second side panel, the third side panel and the fourth side panel can be integrally formed. The first side plate is opposite to the third side plate and arranged in parallel and spaced apart, and the second side plate is opposite to the fourth side plate and arranged in parallel and spaced apart. The first side plate, the second side plate, the third side plate and the fourth side plate together form a space, and the thermosound film 312 is disposed in the space through the first electrode 314 and the second electrode 316 . Two ends of the first electrode 314 and the second electrode 316 are supported by two parallel side plates of the supporting structure 318 . The infrared reflection film 340 and the infrared transmission film 350 preferably have a self-supporting structure. The size of the infrared reflective film 340 and the infrared transmissive film 350 may be consistent with the size of the support structure 318 . The infrared reflective film 340 and the infrared transmissive film 350 can be respectively fixed on the side plate of the supporting structure 318 by means of adhesive or the like. In this embodiment, the infrared reflective film 340 and the infrared transmissive film 350 are respectively fixed on the four side plates of the supporting structure 318 by adhesive. It can be understood that the infrared transmissive film 350 in this embodiment is an optional structure.

The sounding device provided by the present invention has the following advantages: one, the carbon nanotube structure is used as the thermal sounding film, the carbon nanotube structure has a smaller heat capacity per unit area, the sounding frequency range of the sounding device is wider, and the sounding intensity Higher and better sound. Second, the sounding device provided by the present invention further reflects the infrared rays emitted by the thermal sounding film to the other side of the thermal sounding film to the other side of the thermal sounding film by arranging an infrared reflective film on one side of the sounding module, so that Users on the side of the infrared reflective film will not feel the heat. Second, the sound generating device can be composed of a layered protective structure and a thermal sounding film, and the thermal sounding film is arranged between the two layered protective structures, and the layered protective structure can protect the thermal sounding film to make the thermal sounding The membrane is not easily damaged by external force. Third, the sound generating device may only include a sound generating module, an infrared reflective film, and an infrared transmissive film. At this time, the infrared reflective film and the infrared transmissive film can further protect the thermal sound emitting film, so that the The structure of the sound generating device is relatively simple.

In addition, those skilled in the art can also make other changes within the spirit of the present invention. Of course, these changes made according to the spirit of the present invention should be included within the scope of protection claimed by the present invention.

Claims (20)

1. a sound-producing device, comprising: a sounding module, this sounding module includes multiple being connected with each other the first electrode, multiple it is connected with each other the second electrode and a hot sounding film, the plurality of first electrode and multiple second electrode alternate intervals arrange and electrically connect with this hot sounding film, it is characterized in that, described hot sounding film includes a carbon nano tube structure, described sound-producing device farther includes one first protection structure, one second protection structure, one infrared reflection film and an infrared transmission film, described hot sounding film is arranged between this first protection structure and the second protection structure, described infrared reflection film is arranged on the first protection body structure surface, described infrared transmission film is arranged on the surface of described second protection structure.

2. sound-producing device as claimed in claim 1, it is characterised in that described infrared reflection film and described hot sounding film interval are arranged.

3. sound-producing device as claimed in claim 1, it is characterised in that the infrared reflection rate of described infrared reflection film is be more than or equal to 20% and less than or equal to 100%.

4. sound-producing device as claimed in claim 1, it is characterised in that described infrared reflection film includes a matrix and is arranged on a reflectance coating of this matrix surface.

5. sound-producing device as claimed in claim 4, it is characterised in that described matrix includes polymeric film or fabric.

6. sound-producing device as claimed in claim 4, it is characterised in that described reflectance coating is metallic reflective coating, and this metal is gold, silver or copper.

7. sound-producing device as claimed in claim 4, it is characterized in that, described infrared reflection film farther includes at least one dielectric film and is arranged on the described reflectance coating surface away from matrix, and the material of this dielectric film is silicon oxide, Afluon (Asta), silicon dioxide or aluminium sesquioxide.

8. sound-producing device as claimed in claim 1, it is characterised in that the material of described infrared transmission film is zinc sulfide, zinc selenide, diamond or diamond-like-carbon.

9. sound-producing device as claimed in claim 8, it is characterised in that the infrared light transmission of described infrared transmission film is be more than or equal to 10% and less than or equal to 99%.

10. sound-producing device as claimed in claim 1, it is characterised in that described first protection structure and the second protection structure have multiple through hole.

11. sound-producing device as claimed in claim 10, it is characterised in that multiple through hole gross areas of described first protection structure and the second protection structure account for the percentage ratio of the area of this first protection structure and the second protection structure respectively between 20% to 99%.

12. sound-producing device as claimed in claim 1, it is characterised in that described carbon nano tube structure includes at least one carbon nano-tube film.

13. sound-producing device as claimed in claim 12, it is characterised in that described carbon nano-tube film includes multiple CNT and joins end to end and be substantially arranged of preferred orient in the same direction, is connected with each other by Van der Waals force between CNT.

14. sound-producing device as claimed in claim 13, it is characterised in that described carbon nano tube structure includes multiple CNT film-stack and arranges.

15. sound-producing device as claimed in claim 1, it is characterised in that the unit are thermal capacitance of described hot sounding film is less than 2 × 10^-4Joules per cm Kelvin.

16. sound-producing device as claimed in claim 1, it is characterised in that described hot sounding film is unsettled at least partly to be arranged between described first protection structure and described second protection structure.

17. sound-producing device as claimed in claim 16, it is characterised in that described hot sounding film is arranged between described first protection structure and described second protection structure by described at least two the first electrode and at least two the second electrode are unsettled at least partly.

18. a sound-producing device, it is connected with each other the first electrode comprising: multiple, multiple it is connected with each other the second electrode and a hot sounding film, this first electrode and the second electrode alternate intervals arrange and electrically connect with this hot sounding film, it is characterized in that, described hot sounding film includes a carbon nano tube structure, and described sound-producing device farther includes an infrared reflection film and an infrared transmission film, and described hot sounding film is arranged between this infrared reflection film and infrared transmission film.

19. sound-producing device as claimed in claim 18, it is characterised in that farther including a supporting construction, described at least one first electrode and at least one second electrode are supported by this supporting construction.

20. sound-producing device as claimed in claim 19, it is characterised in that described infrared reflection film and infrared transmission film are fixedly installed on described supporting construction and described hot sounding film interval setting.