Microphone

Abstract

A microphone, comprising a packaging housing having an inner cavity, a sound hole for sound to flow into the inner cavity being provided on the packaging housing, a diaphragm being disposed in the inner cavity, and the diaphragm dividing the inner cavity into a front cavity close to the side of the sound hole and a back cavity distant from the side of the sound hole. An air permeable barrier is disposed in the back cavity, the air permeable barrier having a Gurley air resistance of less than 10s, a thickness of less than 80 μm, and a maximum pore diameter of less than 50 μm. The air permeable barrier and an inner wall of the back cavity enclosingly form a partition cavity, or a partition cavity is formed inside the air permeable barrier, the partition cavity being filled with a porous material component. The microphone of the present application can virtually expand the volume of a back cavity, effectively increasing the sensitivity and the signal-to-noise ratio of the microphone, improving the performance of the microphone, and can also effectively reduce the impact of falling powder on the diaphragm.

Description

Microphone

[0001] Related Applications

[0002] This application claims priority to Chinese Patent Application No. 202422355016.6, filed on September 26, 2024, and incorporates by reference the entire disclosure of the aforementioned patent application as part of this application. TECHNICAL FIELD

[0003] The present application relates to the field of audio, in particular to a microphone. BACKGROUND

[0004] A condenser microphone is a device that converts sound signals into electrical signals. It uses the principle of a capacitor to sense the changes in sound waves. Condenser microphones have very flat frequency response and high sensitivity, so they are often used in professional audio applications such as recording studios, live performances, and measurements.

[0005] Currently, the condenser microphones on the market have a relatively compact packaging space, resulting in a small volume of the rear cavity of the microphone, which in turn causes the signal-to-noise ratio of the microphone to be low, seriously affecting the performance of the microphone. SUMMARY

[0006] The purpose of the embodiments of the present application is to provide a microphone that can virtually expand the volume of the rear cavity, effectively improve the sensitivity and signal-to-noise ratio of the microphone, and improve the performance of the microphone, and also effectively reduce the impact of falling powder on the diaphragm.

[0007] The purpose of the embodiments of the present application is achieved by providing a microphone, which includes a packaging shell having an inner cavity, a sound hole is formed on the packaging shell for sound to flow into the inner cavity, a diaphragm is arranged in the inner cavity, and the diaphragm divides the inner cavity into a front cavity close to the sound hole and a rear cavity away from the sound hole; a gas-permeable barrier is arranged in the rear cavity, the gas-permeable barrier has a Gurley air permeability resistance less than 10 s, a thickness less than 80 μm, and a maximum pore size less than 50 μm; the gas-permeable barrier and the inner wall of the rear cavity enclose a separation cavity, or the separation cavity is formed in the gas-permeable barrier, and the separation cavity is filled with a porous material.

[0008] In an optional embodiment of the present application, the material of the gas-permeable barrier is polypropylene, polyethylene terephthalate, or polyimide; the gas-permeable barrier has a Gurley air permeability resistance less than 4 s, a thickness less than 50 μm, and a maximum pore size less than 20 μm.

[0009] In an optional embodiment of the present application, the gas-permeable barrier is a gas-permeable film, the gas-permeable film is sleeved on a support ring, and the support ring with the sleeved gas-permeable film is clamped on the inner wall of the rear cavity; or the gas-permeable film is adhesively fixed on the inner wall of the rear cavity.

[0010] In an optional embodiment of the present application, the air-permeable barrier is an air-permeable film, the air-permeable film is sleeved on a porous sheet, the porous sheet sleeved with the air-permeable film is clamped on the inner wall of the rear cavity; or, a porous sheet is clamped on the inner wall of the rear cavity, the porous sheet and the inner wall of the rear cavity enclose a partition cavity, and the air-permeable film is adhered to the surface of the partition cavity opposite to the porous sheet.

[0011] In an optional embodiment of the present application, the density of the porous sheet is 0.1-0.5 g / m 3 , and the thickness is 0.2-3 mm.

[0012] In an optional embodiment of the present application, the air-permeable barrier is an air-permeable film, the air-permeable film is sleeved on a porous sheet, the porous sheet sleeved with the air-permeable film is clamped on the inner wall of the rear cavity; or, a porous sheet is clamped on the inner wall of the rear cavity, the porous sheet and the inner wall of the rear cavity enclose a partition cavity, and the air-permeable film is adhered to the surface of the partition cavity opposite to the porous sheet.

[0013] In an optional embodiment of the present application, the microphone is a condenser microphone, and the porous material piece includes porous particles, porous powders, porous sheet bodies and / or porous block bodies.

[0014] In an optional embodiment of the present application, the packaging shell includes a substrate and a shell arranged on the substrate, and the substrate and the shell enclose an inner cavity; a substrate and an ASIC chip are arranged on the substrate and located in the inner cavity, a diaphragm and a back plate are arranged on the substrate, and an air gap is arranged between the diaphragm and the back plate.

[0015] In an optional embodiment of the present application, the sound hole is arranged on the shell, the closed space surrounded by the diaphragm, the substrate and the shell constitutes a rear cavity, and the space surrounded by the diaphragm, the substrate, the shell and the shell constitutes a front cavity.

[0016] In an optional embodiment of the present application, the sound hole is arranged on the substrate and corresponds to the position of the diaphragm, the space surrounded by the diaphragm, the substrate and the shell constitutes a front cavity, and the closed space surrounded by the diaphragm, the substrate, the shell and the shell constitutes a rear cavity.

[0017] In an optional embodiment of the present application, the packaging shell includes a first substrate and a second substrate arranged on the first substrate, and the first substrate and the second substrate enclose an inner cavity; a substrate and an ASIC chip are arranged on the first substrate and located in the inner cavity, a diaphragm and a back plate are arranged on the substrate, and an air gap is arranged between the diaphragm and the back plate; the sound hole is arranged on the first substrate and corresponds to the position of the diaphragm, the space surrounded by the diaphragm, the substrate and the first substrate constitutes a front cavity, and the closed space surrounded by the diaphragm, the substrate, the first substrate and the second substrate constitutes a rear cavity.

[0018] In an optional embodiment of the present application, the packaging shell comprises a circuit board and a shell arranged on the circuit board, the circuit board and the shell enclosing an inner cavity; a solder pad is arranged on the outer wall of the circuit board, and a field effect tube is arranged on the circuit board and located in the inner cavity; a mounting port is arranged on the shell, the mounting port is provided with a diaphragm and a back plate arranged in an inner-outer interval along the axial direction of the mounting port, an air gap is arranged between the diaphragm and the back plate, and a perforation is arranged on the back plate to form a sound hole; the diaphragm, the inner wall of the mounting port and the back plate enclose a front cavity, and the space enclosed by the diaphragm, the shell and the circuit board forms a rear cavity.

[0019] As described above, the microphone of the embodiment of the present application divides the rear cavity into a partitioned cavity by arranging the air-permeable barrier in the rear cavity of the microphone, enclosing the rear cavity with the air-permeable barrier or forming a cavity in the air-permeable barrier itself, arranging a porous material in the partitioned cavity, achieving the acoustic effect of a large cavity in a miniaturized microphone assembly, effectively improving the sensitivity of the microphone and the signal-to-noise ratio of the microphone. At the same time, the air-permeable barrier has high air permeability and can fully exchange gas, further improving the acoustic effect; the air-permeable barrier itself is thin and small in size, which is more conducive to filling more materials; the air-permeable barrier can also effectively prevent the porous material from falling onto the diaphragm and effectively reduce the impact of the falling powder on the diaphragm. BRIEF DESCRIPTION OF DRAWINGS

[0020] The following drawings are only intended to illustrate and explain the present application and do not limit the scope of the present application. Among them:

[0021] Fig. 1 is a structural diagram of a microphone provided by an embodiment of the present application.

[0022] Fig. 2 is a sectional view of the microphone provided by an embodiment of the present application.

[0023] Fig. 3 is a structural diagram of a microphone provided by another embodiment of the present application.

[0024] Fig. 4 is a sectional view of the microphone provided by another embodiment of the present application.

[0025] Fig. 5 is a structural diagram of a microphone provided by yet another embodiment of the present application.

[0026] Fig. 6 is a sectional view of the microphone provided by yet another embodiment of the present application.

[0027] Fig. 7 is a structural diagram of a microphone provided by still another embodiment of the present application.

[0028] Fig. 8 is a sectional view of the microphone provided by still another embodiment of the present application.

[0029] Explanation of reference numerals: 1. Encapsulation housing; 11. Acoustic aperture; 12. Front cavity; 13. Rear cavity; 131. Vent barrier; 14. Substrate; 15. Outer shell; 151. Mounting port; 16. First substrate; 17. Second substrate; 18. Circuit board; 19. Solder pad; 2. Porous material component; 3. Substrate; 4. Diaphragm; 5. Back electrode plate; 6. ASIC chip; 7. Field effect transistor; 10. Inner cavity; 20. Separation cavity. Detailed Implementation

[0030] To provide a clearer understanding of the technical features, objectives, and effects of this application, specific embodiments of this application will now be described with reference to the accompanying drawings.

[0031] As shown in Figures 1 to 8, this application provides a microphone, including a housing 1 with an inner cavity 10. A sound hole 11 is provided on the housing 1 to allow sound to flow into the inner cavity 10. A diaphragm 4 is provided in the inner cavity 10, which divides the inner cavity into a front cavity 12 near the sound hole 11 and a rear cavity 13 away from the sound hole 11. A breathable barrier 131 is provided in the rear cavity 13. The breathable barrier 131 has a Gurley-air permeability (s / 100cc) of less than 10s, a thickness of less than 80μm, and a maximum pore size of less than 50μm. The breathable barrier 131 and the inner wall of the rear cavity 13 enclose a partition cavity 20, or the breathable barrier 131 forms a partition cavity 20. A porous material 2 is filled in the partition cavity 20.

[0032] Therefore, in this embodiment of the microphone, by providing a breathable barrier 131 within the rear cavity 13 of the microphone, and by either enclosing the rear cavity 13 with the inner wall of the rear cavity 13 or forming a cavity within the breathable barrier 131 itself, a partition cavity 20 is created within the partition cavity. A porous material component 2 is then placed within the partition cavity. This achieves the acoustic effect of a large cavity in a miniaturized microphone assembly, effectively improving the microphone's sensitivity and signal-to-noise ratio. Simultaneously, the high permeability of the breathable barrier 131 allows for ample gas exchange, further enhancing the acoustic effect. The thin and small size of the breathable barrier 131 facilitates the filling of more material. Furthermore, the breathable barrier 131 effectively prevents porous material from falling onto the diaphragm 4, effectively reducing the impact of dust on the diaphragm 4.

[0033] The porous material component 2 described above can be one or more of porous particles, porous powders, porous sheets, and porous blocks. When the porous material component 2 adopts a sheet structure or a block structure, the signal-to-noise ratio and sensitivity of the microphone are higher than when porous particles or porous powders are used.

[0034] Further preferably, the air permeable barrier 131 has a Gurley air permeability of less than 4 s, a thickness of less than 50 pm, and a maximum pore size of less than 20 pm. Still further preferably, the air permeable barrier 131 has a Gurley air permeability of less than 1 s, a thickness of less than 30 pm, and a maximum pore size of less than 10 pm. With these parameters, the air permeable barrier 131 is even thinner and can be filled with more material. The material of the air permeable barrier 131 is preferably polypropylene (PP), polyethylene terephthalate (PET), or polyimide (PI).

[0035] The porous material piece 2 contains a porous material, which is a combination of one or more of zeolite, activated carbon, MOF, COF, aerogel, and hydrogel. The porous material piece 2 preferably contains zeolite, which has a better signal-to-noise ratio and sensitivity than activated carbon. The zeolite material has good absorption and release capacity for air, can virtually expand the volume of the back cavity 13, and better improve the performance of the microphone. In some embodiments, the porous material piece 2 is in the form of a powder, and the size of the powder is 50-300 nm. In some embodiments, the porous material piece 2 is in the form of a particle, and the size of the particle is 10-300 pm. In some embodiments, the porous material piece 2 is in the form of a sheet, and the density is 0.1-0.5 g / m 3 , and the thickness is 0.1-1 mm. In some embodiments, the porous material piece 2 is in the form of a block, and the density is 0.1-0.5 g / m 3 , and the thickness is 1-3 mm.

[0036] In some embodiments, the air permeable barrier 131 is fixed on the inner wall of the back cavity 13. The air permeable barrier 131 can be a combination of one or more of hard PET mesh and air-permeable film, and the air permeable barrier 131 is more preferably an air-permeable film, which has better powder leakage prevention performance and can ensure the long-term and stable operation of the MEMS. In some embodiments, the air permeable barrier 131 of the hard PET mesh is clamped in the groove or buckle inside the corresponding shell of the back cavity 13.

[0037] In some embodiments, the air permeable barrier 131 is an air-permeable film and is sleeved on a support ring (such as a plastic ring or a metal ring), and the support ring with the air permeable barrier 131 sleeved thereon is clamped in the clamping groove of the inner wall of the back cavity 13; or, the air permeable barrier 131 is fixed on the inner wall of the back cavity 13 by an adhesive or double-sided adhesive.

[0038] In some embodiments, the air permeable barrier 131 is an air-permeable film and is sleeved on a porous sheet, and the porous sheet with the air permeable barrier 131 sleeved thereon is clamped in the clamping groove of the inner wall of the back cavity 13; or, a porous sheet is clamped in the clamping groove of the inner wall of the back cavity 13, the porous sheet and the inner wall of the back cavity 13 enclose the above-mentioned separation cavity 20, and the air permeable barrier 131 is heated and softened and adhered to the surface of the separation cavity 20 opposite to the porous sheet.

[0039] In this embodiment, the porous sheet is made of porous material and has a certain air permeability. The density of the porous sheet is preferably 0.1-0.5 g / m 3 2, and the thickness is preferably 0.2-3 mm. By providing the porous sheet, the air permeable barrier 131 can be supported, and the possibility of the porous material falling on the diaphragm 4 can be further reduced, and the influence of the falling powder on the diaphragm 4 can be more effectively reduced. In particular, for a MEMS microphone, the diaphragm 4 is small in volume, and the influence of the falling powder is great. The cooperation of the air permeable barrier 131 and the porous sheet in this embodiment can well avoid the influence.

[0040] In some embodiments, the air permeable barrier 131 is an air permeable film, which wraps the porous material piece 2 and is assembled in the back cavity 13. For example, the air permeable film wrapped around the porous material piece 2 can be placed in the back cavity 13, clamped on the clamping groove of the inner wall of the back cavity 13, or bonded to the inner wall of the back cavity 13.

[0041] In order to better illustrate the effect of the microphone of the present application, the following takes the structure of a MEMS microphone as an example to test the signal-to-noise ratio and sensitivity of several specific embodiments provided with the above-mentioned air permeable barrier 131 and porous material piece 2 in the back cavity 13 and a blank comparative example without the air permeable barrier 131 and the porous material piece 2, for further comparison and illustration, as follows:

[0042] Embodiment 1

[0043] The air permeable barrier 131 is a hard PET mesh cloth (Gurley air permeability resistance is 0.2 s, thickness is 40 μm, and maximum pore size is 10 μm), which is clamped in the groove inside the corresponding shell of the back cavity 13, and the inner wall of the corresponding shell of the back cavity 13 forms a closed separation cavity 20. The volume of the separation cavity 20 is 0.001 CC. In the separation cavity 20, 0.001 CC of porous particles is filled, and the average diameter of the porous particles is 50 μm.

[0044] Embodiment 2

[0045] The air permeable barrier 131 is an air permeable film (Gurley air permeability resistance is 3.5 s, thickness is 45 μm, and maximum pore size is 10 nm), which is sleeved on a supporting metal ring and clamped in the groove of the inner wall of the back cavity 13, and the inner wall of the corresponding shell of the back cavity 13 forms a closed separation cavity 20. The volume of the separation cavity 20 is 0.001 CC. In the separation cavity 20, 0.001 CC of porous powder is filled, and the average diameter of the porous powder is 15 nm.

[0046] Embodiment 3

[0047] The air-permeable barrier 131 is an air-permeable film (the parameters of the air-permeable film are the same as those in Example 2), and a porous sheet is clamped in the clamping groove of the inner wall of the rear cavity 13. The porous sheet and the inner wall of the rear cavity 13 form the above-mentioned separation cavity 20, and the air-permeable barrier 131 is heated and softened and adhered to the surface of the separation cavity 20 opposite to the porous sheet. The porous sheet contains zeolite, binder and fiber, and has a density of 0.2 g / m 3 and a thickness of 0.1 mm. The separation cavity 20 is filled with 0.001 CC of porous particles, and the average diameter of the porous particles is 50 μm.

[0048] Example 4

[0049] The air-permeable barrier 131 is an air-permeable film (the parameters of the air-permeable film are the same as those in Example 2), and a porous sheet is clamped in the clamping groove of the inner wall of the rear cavity 13. The porous sheet and the inner wall of the rear cavity 13 form the above-mentioned separation cavity 20, and the air-permeable barrier 131 is heated and softened and adhered to the surface of the separation cavity 20 opposite to the porous sheet. The porous sheet contains zeolite, binder and fiber, and has a density of 0.2 g / m 3 and a thickness of 0.1 mm. The separation cavity 20 has a volume of 0.001 CC. The separation cavity 20 is filled with 0.001 CC of porous powder, and the average diameter of the porous powder is 15 nm.

[0050] Example 5

[0051] The air-permeable barrier 131 is an air-permeable film (the parameters of the air-permeable film are the same as those in Example 2), and wraps the porous powder and is adhered in the rear cavity 13 by an adhesive. The bulk volume of the powder is 0.001 CC, and the average diameter is 15 nm.

[0052] Example 6

[0053] The air-permeable barrier 131 is an air-permeable film (the parameters of the air-permeable film are the same as those in Example 2), and wraps the porous sheet body and is adhered in the rear cavity 13 by an adhesive. The porous sheet body contains zeolite, binder and fiber, and has a density of 0.2 g / m 3 and a thickness of 0.1 mm.

[0054] Blank Comparative Example

[0055] A silicon microphone module without the air-permeable barrier 131 and the porous material piece 2, such as the 3722 MEMS silicon microphone of Zhixuanyin Technology.

[0056] The signal-to-noise ratio and sensitivity of the blank comparative example and the microphones corresponding to the aforementioned Examples 1-6 were tested. The test results are shown in Table 1 below:

[0057] Table 1

[0058] As can be seen from the test results in the above table, by setting the air-permeable barrier 131 in the back cavity 13 of the microphone to separate the partition cavity 20 in the back cavity 13 and setting the porous material piece 2 in the partition cavity 20, the sensitivity and signal-to-noise ratio of the microphone can be effectively improved. In addition, the signal-to-noise ratio when the air-permeable barrier 131 is an air-permeable film is higher than when it is a mesh cloth.

[0059] In some embodiments, the microphone is a condenser microphone, which generally includes a diaphragm 4, a back plate 5, a capacitor, an output terminal, and a packaging shell 1. The diaphragm 4 is usually made of very thin metal or plastic material and is responsible for sensing sound waves and converting them into mechanical vibrations. The back plate 5 is located opposite the diaphragm 4 and is usually made of metal and forms one of the two electrodes of the capacitor with the diaphragm 4; sound waves cause the diaphragm 4 to vibrate, thereby changing the distance between the diaphragm 4 and the back plate 5, and this change in distance is the change in capacitance of the capacitor. The space between the diaphragm 4 and the back plate 5 constitutes a capacitor. When sound waves act on the diaphragm 4, the distance between the diaphragm 4 and the back plate 5 changes, causing the capacitance of the capacitor to change. The output terminal is where the electrical signal output of the microphone is connected to an amplifier or other audio equipment. The packaging shell 1 is the outermost layer of the microphone and is used to protect the internal structure from damage while allowing sound to pass through.

[0060] In this embodiment, according to the different structures of the packaging shell 1 and the different positions of the sound hole 11, there can be several structural forms as follows.

[0061] In one embodiment, the packaging shell 1 includes a substrate 14 and a shell 15 arranged on the substrate 14, and the substrate 14 and the shell 15 enclose to form an inner cavity 10. The substrate 14 is provided with a substrate 3 and an ASIC chip 6 in the inner cavity 10, and the substrate 3 is provided with a diaphragm 4 and a back plate 5, and an air gap is arranged between the diaphragm 4 and the back plate 5.

[0062] In this embodiment, the sound hole 11 can be provided on the shell 15 or on the substrate 14. When the sound hole 11 is provided on the shell 15, referring to FIGS. 1 and 2, the closed space enclosed by the diaphragm 4, the substrate 3, and the substrate 14 constitutes a back cavity 13, and the space enclosed by the diaphragm 4, the substrate 3, the substrate 14, and the shell 15 constitutes a front cavity 12. When the sound hole 11 is provided on the substrate 14, the sound hole 11 corresponds to the position of the diaphragm 4 so that sound waves can reach the diaphragm 4, referring to FIGS. 3 and 4, the space enclosed by the diaphragm 4, the substrate 3, and the substrate 14 constitutes a front cavity 12, and the closed space enclosed by the diaphragm 4, the substrate 3, the substrate 14, and the shell 15 constitutes a back cavity 13.

[0063] In another embodiment, the difference from the embodiments of Figs. 1-4 is that a multi-layer substrate structure is used, and the microphone device (the substrate 3, the ASIC chip 6, the diaphragm 4 and the back plate 5) is arranged in a closed space of the multi-layer substrate. Specifically, referring to Figs. 5 and 6, the package housing 1 includes a first substrate 16 and a second substrate 17 arranged on the first substrate 16, and the first substrate 16 and the second substrate 17 enclose to form the inner cavity 10; the substrate 3 and the ASIC chip 6 are arranged on the first substrate 16 and in the inner cavity 10, the diaphragm 4 and the back plate 5 are arranged on the substrate 3, and the air gap is arranged between the diaphragm 4 and the back plate 5; the sound hole 11 is arranged on the first substrate 16 and corresponds to the position of the diaphragm 4, the space enclosed by the diaphragm 4, the substrate 3 and the first substrate 16 forms the front cavity 12, and the closed space enclosed by the diaphragm 4, the substrate 3, the first substrate 16 and the second substrate 17 forms the back cavity 13.

[0064] It can be understood that the microphones shown in Figs. 1-6 are all MEMS microphones, and in the two embodiments, the substrate 3, the diaphragm 4 and the back plate 5 form a MEMS chip, which is a transducer component for converting sound signals into electrical signals, and is made by MEMS (Micro-Electro-Mechanical System) technology; the ASIC (Application Specific Integrated Circuit) chip is a signal amplifier device, mainly used to amplify the electrical signal output by the MEMS chip for subsequent processing; the specific structure of the MEMS chip and the ASIC chip 6 is prior art. The housing 15 in Figs. 1-4 and the second substrate 17 in Figs. 5 and 6 are both cavity structures with one end open, so as to facilitate the attachment of the housing 15 in Figs. 1-4 and the substrate 14 together and the attachment of the second substrate 17 in Figs. 5 and 6 and the first substrate 16 together, to form the above-mentioned inner cavity 10. In some embodiments, a sound leakage hole is arranged in the back cavity 13 and communicates with the outside.

[0065] In still another embodiment, referring to Figs. 7 and 8, the package housing 1 comprises a circuit board 18 and a shell 15 arranged on the circuit board 18, the circuit board 18 and the shell 15 enclosing the inner cavity 10; a solder pad 19 is arranged on the outer wall of the circuit board 18 (i.e. the side opposite to the shell 15), and the field effect tube 7 is arranged on the circuit board 18 and in the inner cavity 10; the shell 15 is provided with a mounting port 151, and the mounting port 151 is provided with the diaphragm 4 and the back plate 5 arranged in an inner-outer spaced manner along the axis of the mounting port 151 (the plate faces of the diaphragm 4 and the back plate 5 are perpendicular to the axis of the mounting port 151, and the outer peripheries of the diaphragm 4 and the back plate 5 are connected to the inner wall of the mounting port 151), and the air gap is arranged between the diaphragm 4 and the back plate 5, and the perforation is arranged on the back plate 5 and forms the sound hole 11; the diaphragm 4, the inner wall of the mounting port 151 and the back plate 5 enclose the front cavity 12, and the space enclosed by the diaphragm 4, the shell 15 and the circuit board 18 forms the back cavity 13.

[0066] It can be understood that the shell 15 is a cavity structure with one end open, so as to facilitate the shell 15 and the circuit board 18 to be attached together to form the above-mentioned inner cavity 10 in Figs. 7 and 8. The microphone shown in Figs. 7 and 8 belongs to an electret microphone, and the sensitivity and signal-to-noise ratio of the microphone can be effectively improved by arranging the porous material piece 2 in the back cavity 13.

[0067] In some embodiments, the above-mentioned inner cavity 10 is a closed cavity.

[0068] In some embodiments, the above-mentioned inner cavity 10 is not completely closed. According to the actual design requirements, the package housing 1 can be provided with different sizes and shapes of air holes for different process purposes, such as filling of porous materials, sound leakage of modules, etc. It can be understood that improvements to the package housing 1 according to actual design requirements are also within the scope of protection of the present application.

[0069] The above merely illustrates specific embodiments of the present application, and is not intended to limit the scope of the present application. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present application shall fall within the scope of protection of the present application.

Claims

1. A microphone, wherein, The microphone comprises a packaging shell with an inner cavity, a sound hole is formed on the packaging shell for sound to flow into the inner cavity, a diaphragm is arranged in the inner cavity, and the diaphragm divides the inner cavity into a front cavity close to the sound hole and a rear cavity away from the sound hole; A gas-permeable barrier is arranged in the rear cavity, the gas-permeable barrier has a Gurley air permeability of less than 10 s, a thickness of less than 80 μm, and a maximum pore size of less than 50 μm; The gas-permeable barrier and the inner wall of the rear cavity enclose a separation cavity, or the gas-permeable barrier has a separation cavity formed therein, and the separation cavity is filled with a porous material.

2. The microphone according to claim 1, wherein The gas-permeable barrier is made of polypropylene, polyethylene terephthalate or polyimide, has a Gurley air permeability of less than 4 s, a thickness of less than 50 μm, and a maximum pore size of less than 20 μm.

3. The microphone according to claim 1, wherein The gas-permeable barrier is a gas-permeable film, the gas-permeable film is sleeved on a support ring, and the support ring on which the gas-permeable film is sleeved is clamped on the inner wall of the rear cavity; or the gas-permeable film is fixedly bonded to the inner wall of the rear cavity.

4. The microphone according to claim 1, wherein The gas-permeable barrier is a gas-permeable film, the gas-permeable film is sleeved on a porous sheet, and the porous sheet on which the gas-permeable film is sleeved is clamped on the inner wall of the rear cavity; or a porous sheet is clamped on the inner wall of the rear cavity, the porous sheet and the inner wall of the rear cavity enclose the separation cavity, and the gas-permeable film is bonded to the surface of the porous sheet away from the separation cavity.

5. The microphone according to claim 4, wherein The density of the porous sheet is 0.1-0.5 g / m 3 and the thickness is 0.2-3 mm.

6. The microphone according to claim 1, wherein The gas-permeable barrier is a gas-permeable film, the gas-permeable film is wrapped around the outer periphery of the porous material, and the inner wall of the gas-permeable film encloses the separation cavity.

7. The microphone according to claim 1, wherein The microphone is a condenser microphone, and the porous material comprises porous particles, porous powders, porous sheets and / or porous blocks.

8. The microphone according to claim 1, wherein The packaging shell comprises a substrate and a shell arranged on the substrate, and the substrate and the shell enclose the inner cavity; a substrate and an ASIC chip are arranged on the substrate and in the inner cavity, a diaphragm and a back plate are arranged on the substrate, and an air gap is arranged between the diaphragm and the back plate; The sound hole is formed on the shell, the closed space enclosed by the diaphragm, the substrate and the substrate constitutes the rear cavity, and the space enclosed by the diaphragm, the substrate, the substrate and the shell constitutes the front cavity; or the sound hole is formed on the substrate and corresponds to the position of the diaphragm, the space enclosed by the diaphragm, the substrate and the substrate constitutes the front cavity, and the closed space enclosed by the diaphragm, the substrate, the substrate and the shell constitutes the rear cavity.

9. The microphone according to claim 1, wherein The package shell comprises a first substrate and a second substrate arranged on the first substrate, the first substrate and the second substrate enclosing the inner cavity; a substrate and an ASIC chip are arranged on the first substrate and in the inner cavity, a diaphragm and a back plate are arranged on the substrate, and an air gap is arranged between the diaphragm and the back plate; The sound hole is arranged on the first substrate and corresponds to the position of the diaphragm, a space enclosed by the diaphragm, the substrate and the first substrate constitutes the front cavity, and a closed space enclosed by the diaphragm, the substrate, the first substrate and the second substrate constitutes the back cavity.

10. The microphone of claim 1, wherein, The package shell comprises a circuit board and a shell arranged on the circuit board, the circuit board and the shell enclosing the inner cavity; a pad is arranged on the outer wall of the circuit board, and a field effect tube is arranged on the circuit board and in the inner cavity; A mounting port is arranged on the shell, a diaphragm and a back plate are arranged in the mounting port and spaced apart in the axial direction of the mounting port, an air gap is arranged between the diaphragm and the back plate, a perforation is arranged on the back plate and constitutes the sound hole; the diaphragm, the inner wall of the mounting port and the back plate enclose the front cavity, and a space enclosed by the diaphragm, the shell and the circuit board constitutes the back cavity.

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