Microphone

Abstract

The utility model relates to a microphone, which comprises an inner cavity enclosed by a packaging shell, a sound hole for sound to flow into the inner cavity is arranged on the packaging shell, a vibrating diaphragm is arranged in the inner cavity, the vibrating diaphragm divides the inner cavity into a front cavity close to one side of the sound hole and a rear cavity far away from one side of the sound hole, and a porous material piece is arranged in the front cavity. The microphone provided by the utility model can effectively improve the tone quality and sensitivity of the microphone, and reduces noise interference.

Description

Technical Field

[0001] The utility model relates to the technical field of audio, and particularly relates to a microphone. Background Art

[0002] A capacitive microphone is a device that converts sound signals into electrical signals, and it uses the principle of a capacitor to sense the changes in sound waves. Capacitive microphones have a very flat frequency response and high sensitivity, so they are usually used in professional audio applications such as recording studios, live performances, and measurements.

[0003] However, in the process of sound acquisition, traditional capacitive microphones often have problems such as poor sound quality, low sensitivity, and susceptibility to external noise interference. Therefore, it is necessary to optimize the design of capacitive microphones to improve their acoustic performance and stability. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a microphone that can effectively improve the sound quality and sensitivity of the microphone and reduce noise interference.

[0005] The purpose of the utility model is realized as follows: A microphone includes an inner cavity surrounded by a packaging shell. A sound hole for sound to flow into the inner cavity is opened on the packaging shell. A diaphragm is arranged in the inner cavity. The diaphragm divides the inner cavity into a front cavity close to the sound hole and a rear cavity far from the sound hole. A porous material piece is arranged in the front cavity.

[0006] In a preferred embodiment of the utility model, the porous material piece includes porous particles. The porous particles are installed in a breathable bag and filled in the front cavity.

[0007] In a preferred embodiment of the utility model, the porous material piece includes porous powder. The porous powder is installed in a breathable bag and filled in the front cavity.

[0008] In a preferred embodiment of the utility model, the porous material piece is in a sheet structure, a block structure, or a film layer structure, and is adhesively fixed on the inner wall of the front cavity.

[0009] In a preferred embodiment of the utility model, the porous material piece is in a coating structure and is sprayed on the inner wall of the front cavity.

[0010] In a preferred embodiment of the utility model, the microphone is a capacitive microphone.

[0011] In a preferred embodiment of the utility model, the packaging shell includes a substrate and a housing arranged on the substrate. The substrate and the housing enclose to form the inner cavity. A substrate and an ASIC chip are arranged in the inner cavity on the substrate. A diaphragm and a back plate are arranged on the substrate. An air gap is arranged between the diaphragm and the back plate.

[0012] In a preferred embodiment of the present utility model, sound holes are formed in the outer shell, and the closed space formed by the diaphragm, the substrate and the base plate constitutes the rear cavity, and the space formed by the diaphragm, the substrate, the base plate and the outer shell constitutes the front cavity.

[0013] In a preferred embodiment of the present utility model, sound holes are formed in the base plate and correspond to the position of the diaphragm. The space formed by the diaphragm, the substrate and the base plate constitutes the front cavity, and the closed space formed by the diaphragm, the substrate, the base plate and the outer shell constitutes the rear cavity.

[0014] In a preferred embodiment of the present utility model, the packaging shell includes a first base plate and a second base plate provided on the first base plate. The first base plate and the second base plate enclose to form an inner cavity; a substrate and an ASIC chip are provided on the first base plate and located in the inner cavity. A diaphragm and a back plate are provided on the substrate, and an air gap is provided between the diaphragm and the back plate; sound holes are formed in the first base plate and correspond to the position of the diaphragm. The space formed by the diaphragm, the substrate and the first base plate constitutes the front cavity, and the closed space formed by the diaphragm, the substrate, the first base plate and the second base plate constitutes the rear cavity.

[0015] As described above, for the microphone of the present utility model, by arranging a porous material piece in the front cavity, the reflection and resonance phenomena of sound waves in the front cavity can be effectively reduced, the transmission effect of sound waves can be effectively improved, the effective control of sound waves is realized, the sensitivity and signal-to-noise ratio of the microphone are improved, the noise interference is reduced, and thus the user experience is enhanced. Moreover, the structure is simple and the cost is low, and it can be widely applied to various microphone products to improve the product competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following drawings are only intended to illustrate and explain the present utility model schematically and do not limit the scope of the present utility model. Among them:

[0017] Figure 1 : is a schematic structural diagram of the microphone provided by the present utility model.

[0018] Figure 2 : is another schematic structural diagram of the microphone provided by the present utility model.

[0019] Figure 3 : is another schematic structural diagram of the microphone provided by the present utility model.

[0020] Explanation of the reference numerals in the drawings:

[0021] 1. Packaging shell; 11. Sound hole; 12. Front cavity; 13. Rear cavity; 14. Base plate; 15. Outer shell; 16. First base plate; 17. Second base plate;

[0022] 2. Porous material piece;

[0023] 3. Substrate;

[0024] 4. Diaphragm;

[0025] 5. Backplate;

[0026] 6. ASIC chip. Detailed implementation manner

[0027] For a clearer understanding of the technical features, objectives, and effects of the present utility model, the specific implementation manner of the present utility model will now be described with reference to the accompanying drawings.

[0028] As Figures 1 to 3 shown, this embodiment provides a microphone, which includes an inner cavity surrounded by a packaging housing 1. A sound hole 11 for sound to flow into the inner cavity is provided on the packaging housing 1. A diaphragm 4 is provided in the inner cavity. The diaphragm 4 divides the inner cavity into a front cavity 12 on the side close to the sound hole 11 and a rear cavity 13 on the side far from the sound hole 11. A porous material member 2 is provided in the front cavity 12.

[0029] Thus, in the microphone of this embodiment, by providing the porous material member 2 in the front cavity 12, the reflection and resonance phenomena of sound waves in the front cavity 12 can be effectively reduced, the transmission effect of sound waves can be effectively improved, the effective control of sound waves is achieved, the sound quality is improved, the sensitivity and signal-to-noise ratio of the microphone are increased, the noise interference is reduced, and thus the user experience is enhanced. Moreover, the structure is simple, the cost is low, and it can be widely applied to various microphone products to enhance the product competitiveness.

[0030] In a specific implementation manner, the porous material member 2 may include porous particles, and the porous particles are installed in a breathable bag and filled in the front cavity 12. Alternatively, the porous material member 2 may also include porous powder, and the porous powder is installed in a breathable bag and filled in the front cavity 12. Alternatively, the porous material member 2 may also be in a sheet structure, a block structure, or a film layer structure, and is adhesively fixed to the inner wall of the front cavity 12, for example, fixed to the inner wall of the front cavity 12 through an adhesive or double-sided tape. Alternatively, the porous material member 2 may also be in a coating structure and sprayed on the inner wall of the front cavity 12.

[0031] When the porous material member 2 adopts a sheet structure or a block structure, the signal-to-noise ratio and sensitivity of the microphone are the highest. When it adopts porous particles or porous powder, the signal-to-noise ratio and sensitivity of the microphone are the second highest. When it adopts a film layer structure or a coating structure, they are the next highest. The specific form and fixing method of the porous material can be determined according to actual needs. This embodiment is only for illustrative purposes.

[0032] In some embodiments, the porous material piece 2 contains a porous material, which is a combination of one or more of zeolite, activated carbon, MOF, COF, aerogel, hydrogel, etc. Preferably, the porous material piece 2 contains zeolite. When using zeolite, the corresponding signal-to-noise ratio and sensitivity are better than when using activated carbon. Further optionally, the porous material piece 2 also includes a combination of one or more of a foaming material (such as open-cell foam, used to absorb high-frequency sound waves and reduce sound wave reflection), a fiber material (such as glass fiber, rock wool, etc., having good porous properties and heat resistance), and an elastic material, etc. These materials have good porous properties, low reflectivity, and good damping properties, and can effectively absorb and disperse sound wave energy, reduce sound wave reflection and resonance in the front cavity 12, and significantly improve the sound quality performance of the microphone. At the same time, the density and thickness of the material can be adjusted according to actual needs to achieve the best sound quality effect and thus adapt to different application scenarios.

[0033] To better illustrate the effect of the microphone of the present invention, taking the structure of a MEMS microphone as an example, several specific embodiments with the above-mentioned porous material piece 2 provided in the front cavity 12 and a blank comparative example without the porous material piece 2 are respectively tested for signal-to-noise ratio and sensitivity for further comparative illustration, as follows:

[0034] Example 1

[0035] The porous material piece 2 is porous particles, which are filled in the front cavity 12 after being filled in a breathable bag. The material of the porous particles is zeolite, and the volume after being installed in the breathable bag is 2CC, and the average diameter of the porous particles is 100μm.

[0036] Example 2

[0037] The porous material piece 2 is porous particles, which are filled in the front cavity 12 after being filled in a breathable bag. The material of the porous particles is activated carbon, and the volume after being installed in the breathable bag is 2CC, and the average diameter of the porous particles is 100μm.

[0038] Example 3

[0039] The porous material piece 2 is a sheet structure and is adhesively fixed on the inner wall of the front cavity 12. The material of the sheet structure contains zeolite, the volume is 4CC, and the thickness is 1mm.

[0040] Example 4

[0041] The porous material piece 2 is a film layer structure and is adhesively fixed on the inner wall of the front cavity 12. The material of the film layer structure is zeolite, the thickness is 10μm, and 5 film layers are stacked.

[0042] Blank comparative example

[0043] No porous material piece 2 is provided in the front cavity.

[0044] Test the signal-to-noise ratio and sensitivity of the blank control example and the microphones corresponding to the foregoing Examples 1-4. The test results are shown in Table 1 below:

[0045] Table 1

[0046]

[0047] It can be seen from the test results in the above table that by arranging the porous material member 2 in the front cavity 12 of the microphone, the sensitivity and signal-to-noise ratio of the microphone can be effectively improved. Among them, when the porous material member 2 adopts a sheet structure, the corresponding signal-to-noise ratio and sensitivity are the best, followed by the corresponding signal-to-noise ratio and sensitivity when adopting porous particles, and the corresponding signal-to-noise ratio and sensitivity are the next best when adopting a film layer structure. When the material of the porous material member 2 is zeolite, the corresponding signal-to-noise ratio and sensitivity are better than when adopting activated carbon.

[0048] In some embodiments, the microphone is a capacitive microphone. Generally, a microphone mainly includes a diaphragm 4, a backplate 5, a capacitor, a power supply, an output terminal, and a packaging housing 1. The diaphragm 4 is usually made of a very thin metal or plastic material, and it is responsible for sensing sound waves and converting them into mechanical vibrations. The backplate 5 is located opposite to the diaphragm 4, is usually made of metal, and forms two electrodes of a capacitor with the diaphragm 4; the sound waves cause the vibration of the diaphragm 4, thereby changing the distance between the diaphragm 4 and the backplate 5, and this change in distance is the capacitance change of the capacitor. The space between the diaphragm 4 and the backplate 5 constitutes a capacitor; when sound waves act on the diaphragm 4, the distance between the diaphragm 4 and the backplate 5 changes, resulting in a change in the capacitance value of the capacitor. The microphone requires a DC power supply to maintain the voltage between the two poles of the capacitor, and this voltage is usually constant. The output terminal is the place where the electrical signal of the microphone is output and can be connected to an amplifier or other audio devices. The packaging housing 1 is located on the outermost layer of the microphone, which is used to protect the internal structure from damage and at the same time allows sound to pass through.

[0049] In this embodiment, according to the different structures of the packaging housing 1 and the different positions of the sound holes 11, the following several structural forms can be obtained.

[0050] In one embodiment, the packaging housing 1 includes a substrate 14 and a housing 15 provided on the substrate 14, and the substrate 14 and the housing 15 enclose to form an inner cavity; a substrate 3 and an ASIC chip 6 are provided on the substrate 14 and located in the inner cavity, a diaphragm 4 and a backplate 5 are provided on the substrate 3, and an air gap is provided between the diaphragm 4 and the backplate 5.

[0051] In this embodiment, the sound hole 11 can be opened on the housing 15 or on the substrate 14. When the sound hole 11 is opened on the housing 15, refer to Figure 1, the enclosed space formed by the diaphragm 4, the substrate 3, and the base plate 14 constitutes the rear cavity 13, and the space formed by the diaphragm 4, the substrate 3, the base plate 14, and the housing 15 constitutes the front cavity 12. The porous material member 2 can be provided, for example, on the inner wall of the housing 15. When the sound hole 11 is opened on the base plate 14, the position of the sound hole 11 corresponds to that of the diaphragm 4. Refer to Figure 2 , the space formed by the diaphragm 4, the substrate 3, and the base plate 14 constitutes the front cavity 12, and the enclosed space formed by the diaphragm 4, the substrate 3, the base plate 14, and the housing 15 constitutes the rear cavity 13. The porous material member 2 can be provided, for example, on the inner wall of the substrate 3.

[0052] In another embodiment, refer to Figure 3 , the encapsulation housing 1 includes a first base plate 16 and a second base plate 17 provided on the first base plate 16. The first base plate 16 and the second base plate 17 enclose to form an inner cavity; a substrate 3 and an ASIC chip 6 are provided on the first base plate 16 and located in the inner cavity. A diaphragm 4 and a back plate 5 are provided on the substrate 3, and an air gap is provided between the diaphragm 4 and the back plate 5; the sound hole 11 is opened on the first base plate 16 and corresponds to the position of the diaphragm 4. The space formed by the diaphragm 4, the substrate 3, and the first base plate 16 constitutes the front cavity 12, and the enclosed space formed by the diaphragm 4, the substrate 3, the first base plate 16, and the second base plate 17 constitutes the rear cavity 13. The porous material member 2 can be provided, for example, on the inner wall of the substrate 3.

[0053] It can be understood that Figures 1 to 3 In the two types of embodiments shown, the substrate 3, the diaphragm 4, and the back plate 5 constitute a MEMS chip. The MEMS chip is a transducer component that converts sound signals into electrical signals and is fabricated using MEMS (Micro-Electro-Mechanical System) technology; the ASIC (Application Specific Integrated Circuit) chip is a signal amplification device mainly used to amplify the electrical signals output by the MEMS chip for subsequent processing; the specific structures of the MEMS chip and the ASIC chip 6 are prior art. Figure 1 and Figure 2 the housing 15 in Figure 3 and the second base plate 17 in Figure 1 and Figure 2 are both cavity structures with one end open, so as to facilitate Figure 3 the housing 15 and the base plate 14 in

[0054] During specific processing, first select a porous material piece 2 with suitable acoustic properties, such as a porous material, foam material, or fiber material. Then, according to the size and structural characteristics of the microphone, determine the shape and size of the required porous material piece 2. Next, fill the porous material piece 2 into the front cavity 12, ensuring that it fits tightly against the inner wall of the front cavity 12 without leaving any gaps. Finally, test and adjust the microphone to ensure that its sound quality meets the expected effect. It should be noted that the selection of the porous material piece 2 should be determined according to the actual application scenario and requirements. For example, for occasions that require higher sensitivity, materials with a smaller density can be selected; while for occasions that require noise reduction, materials with better porous performance can be selected. In addition, the microphone of this embodiment can also be used in cooperation with other audio processing circuits and devices to achieve more diverse functions and higher sound quality performance.

[0055] The design of the front cavity 12 of the microphone is a key component of the microphone's acoustic performance, which directly affects the sound quality and pickup characteristics of the microphone. Generally, the design of the front cavity 12 mainly has the following purposes: Acoustic impedance matching: To better match the acoustic impedance between the diaphragm 4 of the microphone and the external environment, reduce sound wave reflection, and improve transmission efficiency. Frequency response adjustment: By designing the volume, shape, and material of the front cavity 12, the frequency response of the microphone can be adjusted to enhance or attenuate the sound in specific frequency bands. Wind and pop protection: The design of the front cavity 12 can reduce the influence of airflow generated by wind or speaking on the microphone pickup. Internal acoustic optimization: Optimize the acoustic environment inside the front cavity 12 to reduce internal standing waves and harmonics, and improve the clarity and quality of the sound. In this embodiment, by setting the porous material piece 2 in the front cavity 12, it is aimed to improve the pickup quality of the microphone. The porous material piece 2 can absorb a part of the sound wave energy, reduce sound wave reflection and resonance, and can be used to adjust the frequency response of the microphone, reduce internal resonance, suppress acoustic interference, etc., thereby improving the clarity and naturalness of the sound, optimizing the acoustic performance of the microphone, and improving the pickup quality.

[0056] In some embodiments, the above-mentioned inner cavity is a sealed cavity.

[0057] In some embodiments, the above-mentioned inner cavity is not completely sealed. According to the actual design requirements, the encapsulation housing 1 can be provided with ventilation holes of different sizes and shapes for different technological purposes, such as sound leakage of the module. It can be understood that the improvements made to the encapsulation housing 1 according to the actual design requirements are also within the protection scope of the present utility model.

[0058] The above is only a schematic specific embodiment of the present utility model and is not intended to limit the scope of the present utility model. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present utility model shall fall within the protection scope of the present utility model.

Claims

1. A microphone, characterized in that, It includes an inner cavity surrounded by a packaging housing, a sound hole is provided on the packaging housing for sound to flow into the inner cavity, a diaphragm is provided in the inner cavity, the diaphragm divides the inner cavity into a front cavity on the side close to the sound hole and a rear cavity on the side far from the sound hole, and a porous material member is provided in the front cavity.

2. The microphone according to claim 1, characterized in that, The porous material member includes porous particles, and the porous particles are installed in a breathable bag and filled in the front cavity.

3. The microphone according to claim 1, characterized in that, The porous material member includes porous powder, and the porous powder is installed in a breathable bag and filled in the front cavity.

4. The microphone according to claim 1, characterized in that The porous material member is in a sheet structure, a block structure or a film layer structure, and is adhesively fixed on the inner wall of the front cavity.

5. The microphone according to claim 1, wherein The porous material member is in a coating structure and is sprayed on the inner wall of the front cavity.

6. The microphone according to claim 1, wherein The microphone is a capacitive microphone.

7. The microphone according to claim 1, wherein The packaging housing includes a substrate and a housing provided on the substrate, and the substrate and the housing enclose to form the inner cavity; a substrate and an ASIC chip are provided on the substrate and located in the inner cavity, a diaphragm and a back plate are provided on the substrate, and an air gap is provided between the diaphragm and the back plate.

8. The microphone according to claim 7, wherein The sound hole is provided on the housing, and the closed space surrounded by the diaphragm, the substrate and the substrate forms the rear cavity, and the space surrounded by the diaphragm, the substrate, the substrate and the housing forms the front cavity.

9. The microphone according to claim 7, wherein The sound hole is provided on the substrate and corresponds to the position of the diaphragm, and the space surrounded by the diaphragm, the substrate and the substrate forms the front cavity, and the closed space surrounded by the diaphragm, the substrate, the substrate and the housing forms the rear cavity.

10. The microphone according to claim 1, wherein The packaging housing includes a first substrate and a second substrate provided on the first substrate, and the first substrate and the second substrate enclose to form the inner cavity; a substrate and an ASIC chip are provided on the first substrate and located in the inner cavity, a diaphragm and a back plate are provided on the substrate, and an air gap is provided between the diaphragm and the back plate; The sound hole is provided on the first substrate and corresponds to the position of the diaphragm, and the space surrounded by the diaphragm, the substrate and the first substrate forms the front cavity, and the closed space surrounded by the diaphragm, the substrate, the first substrate and the second substrate forms the rear cavity.

Images