A microphone

Abstract

This invention relates to a microphone, comprising a diaphragm load and a detection circuit. The diaphragm load includes a diaphragm substrate and a carbon nanotube coating applied to the surface of the diaphragm substrate, used to receive external audio signals and convert them into changing electrical signals. The detection circuit is used to detect voltage or current changes on the diaphragm load and extract the audio signals. This invention mainly uses a carbon nanotube-coated diaphragm load element, resulting in a microphone with advantages such as simple structure, high sensitivity, wide size range, broad frequency response, durability, and good weather resistance.

Description

Technical Field

[0001] The present invention relates to the field of electroacoustic technology, and in particular to a microphone. Background Art

[0002] Microphone is a sound-to-electric conversion device, also known as "microphone", "microphone", etc. It is one of the most important electroacoustic devices in the sound system. Its function is to convert sound signals into electrical signals, then send them to the mixer or amplifier, and finally play them out from the speaker system. In other words, the microphone is used to pick up sound in the sound system. It is the first link of the entire sound system, and its performance quality has a great impact on the entire sound system.

[0003] There are many types of microphones, which can be divided into electric, capacitive, electromagnetic, piezoelectric, and semiconductor microphones according to the transducer principle.

[0004] Problems with currently used microphones:

[0005] 1. Low sensitivity: The sensitivity of a microphone refers to its ability to convert sound into electricity. The sensitivity of an ordinary dynamic microphone is generally around -60dB, with higher ones at -50dB, and professional high-sensitivity microphones can reach around -40dB.

[0006] A highly sensitive microphone can pick up louder sounds under the same conditions, which can reduce the burden on the post-amplifier and make it easier to obtain a high signal-to-noise ratio.

[0007] 2. Proximity effect: The proximity effect of a microphone is that when the microphone picks up sound at a close distance, its low-frequency sensitivity will be significantly improved. The closer the distance, the greater the low-frequency output. The lower the frequency, the stronger this proximity effect.

[0008] The proximity effect destroys the good frequency response of the microphone, that is, after passing through this microphone, the low-frequency part of the original sound field will increase abnormally.

[0009] 3. Limited sound pressure tolerance: Excessive sound pressure will cause poor sound pickup quality of the microphone and may damage the microphone. Therefore, microphones have a technical indicator of "maximum tolerable sound pressure". Summary of the invention

[0010] In order to overcome the low sensitivity and poor durability of existing microphones, the present invention proposes a microphone. The microphone uses the excellent physical property of carbon nanotubes that the resistance value changes sharply due to the tiny deformation, and cooperates with a current source or a voltage source to convert the audio signal into a voltage or current signal, thereby completing the sound-to-electricity conversion.

[0011] To achieve the above-mentioned purpose, the present invention provides a microphone, including a diaphragm load and a detection circuit, wherein the diaphragm load includes a diaphragm substrate and a carbon nanotube coating coated on the surface of the diaphragm substrate, which is used to receive external audio signals and convert them into changing electrical signals; the detection circuit is used to detect the voltage or current changes on the diaphragm load and extract the audio signal.

[0012] Preferably, the carbon nanotube coating is coated on one side or both sides of the diaphragm substrate.

[0013] Preferably, the diaphragm substrate is made of a light and thin elastic material.

[0014] Preferably, a current source or a voltage source is also included.

[0015] Preferably, the detection circuit further includes: an amplifier, and the amplifier is used to amplify the electrical signal generated by the diaphragm load.

[0016] The microphone proposed in the present invention adopts a diaphragm element sprayed with carbon nanotubes. The carbon nanotubes have the excellent physical property of a sharp change in resistance value caused by a unique tiny deformation. The structure is simple, the proximity effect is reduced, the sound pressure resistance and the sensitivity of the microphone are improved, and the microphone has good weather resistance and is not afraid of vibration, shock and humid environment. The amplifier in the peripheral detection circuit can directly extract the voltage or current change signal, so the amplifier circuit is easy to optimize, stable and efficient, which is conducive to the implementation of the process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a circuit structure diagram of a microphone using a current source according to an embodiment of the present invention;

[0019] Figure 2 This is another circuit structure diagram of a microphone using a current source according to an embodiment of the present invention;

[0020] Figure 3 A circuit structure diagram of a microphone using a voltage source according to an embodiment of the present invention;

[0021] Figure 4 4 is a structural diagram of a diaphragm load according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to express the technical solutions and advantages of the embodiments of the present invention more clearly, the technical solutions of the present invention are further described in detail below through the accompanying drawings and embodiments.

[0023] Figure 1 FIG. 1 is a circuit diagram of a microphone using a current source according to an embodiment of the present invention. Figure 1 As shown, the present invention proposes a microphone, including: a power supply, a current source, a diaphragm load and a detection circuit.

[0024] In the microphone circuit, the positive electrode of the power supply is connected to one end of the current source, the other end of the current source is connected to one end of the diaphragm load, the negative electrode of the power supply and the other end of the diaphragm load are grounded, and one end of the detection circuit is connected between the diaphragm load and the current source. When the diaphragm load receives an external audio signal, the resistance in the diaphragm load changes. Since the current source provides a stable current, the voltage of the diaphragm load changes. The detection circuit detects the amplified voltage change on the diaphragm load and extracts the audio signal.

[0025] In the microphone, the voltage of the power supply is sometimes unstable. A current source is added to the circuit to provide a stable current so that the microphone is not affected by the voltage of the power supply, thus improving the sensitivity of the microphone.

[0026] In addition, if Figure 2 As shown, the detection circuit also includes an amplifier. The peripheral circuit of the carbon nanotube microphone circuit can be connected to an amplifier. Since the change of the electrical signal in the microphone circuit is relatively small, an amplifier is used to amplify the electrical signal. Because the voltage or current change signal is directly extracted, the amplifier circuit is easy to optimize, stable and efficient, and the peripheral circuit is simple, reducing the cost.

[0027] Specifically, the current source can be replaced by a voltage source. Figure 3 As shown, the present invention also proposes a microphone, including: a power supply, a voltage source, a diaphragm load, a resistor, an amplifier and a detection circuit.

[0028] In the microphone circuit, the positive electrode of the power supply is connected to one end of the voltage source, the other end of the voltage source is connected to one end of the diaphragm load, the other end of the diaphragm load is connected to the resistor, the negative electrode of the power supply and the other end of the resistor are grounded, one end of the amplifier is connected between the diaphragm load and the resistor, and one end of the detection circuit is connected to the other end of the amplifier. When the diaphragm load receives an external audio signal, the resistance in the diaphragm load changes. Since the voltage source provides a stable voltage, the current of the diaphragm load changes, the amplifier amplifies the electrical signal, and the detection circuit detects the amplified current change on the diaphragm load and extracts the audio signal.

[0029] Figure 4 FIG. 1 is a structural diagram of the diaphragm load of the present invention. Figure 4As shown, the diaphragm load includes a diaphragm substrate and a carbon nanotube coating. The carbon nanotube coating is coated on the surface of the diaphragm substrate and is used to convert external audio signals into electrical signals.

[0030] Specifically, the carbon nanotube coating has a resistance value, and the carbon nanotube has a unique physical property of a sharp change in resistance value caused by a small deformation, which converts the audio signal into an electrical signal, thereby completing the sound-to-electricity conversion. This carbon nanotube microphone greatly improves the sensitivity of the microphone, and the carbon nanotube has good stability, so the microphone using carbon nanotubes has good weather resistance and is not afraid of vibration, shock and humid environment.

[0031] The carbon nanotube coating can be applied to one or both sides of the diaphragm substrate by spraying or other methods.

[0032] Specifically, the diaphragm substrate has a light and thin elastic material. The diaphragm substrate is a light and thin elastic material, and the carbon nanotube coating is coated on the surface of the diaphragm substrate. When the sound wave causes it to vibrate, the diaphragm substrate is deformed by the external vibration, and the resistance value of the carbon nanotube coating will change regularly. The current source or voltage source used can obtain a changing voltage signal or current signal. This simplifies the structure of the vibration system and is conducive to the implementation of the process.

[0033] In the example of the present invention, each module realizes the microphone function through the following operations.

[0034] The power supply, current source, diaphragm load, amplifier and detection circuit in the carbon nanotube microphone circuit are as follows: Figure 2 The connection mode is connected, wherein the negative electrode of the power supply and the other end of the diaphragm load are grounded respectively.

[0035] When the microphone is working, the current comes out from the positive electrode of the power supply, flows through the current source and the diaphragm load in sequence, and forms a stable circuit. When the diaphragm load receives an external audio signal, the sound wave causes the diaphragm substrate in the diaphragm load to vibrate, and the resistance of the carbon nanotube coating attached to the diaphragm substrate changes with the vibration. Since the current source in the microphone circuit provides a stable current, the diaphragm load voltage changes. At this time, the diaphragm load completes the conversion of the audio signal into a changing voltage signal.

[0036] The peripheral circuit of the carbon nanotube microphone is connected to an amplifier. Since the voltage signal in the microphone circuit is relatively small, the voltage signal is amplified by an amplifier and then sent to a detection circuit for detecting the voltage change on the diaphragm load and extracting the audio signal therein.

[0037] The microphone proposed in the present invention adopts a diaphragm element sprayed with carbon nanotubes. The carbon nanotubes have the excellent physical property of a sharp change in resistance value caused by a unique tiny deformation. The structure is simple, the proximity effect is reduced, the sound pressure resistance and the sensitivity of the microphone are improved, and the microphone has good weather resistance and is not afraid of vibration, shock and humid environment. The amplifier in the peripheral detection circuit can directly extract the voltage or current change signal, so the amplifier circuit is easy to optimize, stable and efficient, which is conducive to the implementation of the process.

[0038] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A microphone, characterized in that: Including diaphragm load and detection circuit, The diaphragm load includes a diaphragm substrate and a carbon nanotube coating coated on the surface of the diaphragm substrate, wherein the resistance of the carbon nanotube coating changes with the deformation caused by vibration; the diaphragm load is used to receive an external audio signal and convert the external audio signal into a changing electrical signal; The detection circuit is used to detect the voltage or current change on the diaphragm load and extract the audio signal.

2. The microphone according to claim 1, characterized in that The carbon nanotube coating is coated on one side or both sides of the diaphragm substrate.

3. The microphone according to claim 1, characterized in that The diaphragm substrate is made of a light and thin elastic material.

4. The microphone according to claim 1, characterized in that Also includes: Current source or voltage source.

5. The microphone according to claim 1, characterized in that The detection circuit further includes: an amplifier, The amplifier is used to amplify the electrical signal generated by the diaphragm load.

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