Microphones
The present disclosure provides a microphone including at least one acoustoelectric transducer and an acoustic structure. The acoustoelectric transducer is configured to convert a sound signal to an electrical signal. The acoustic structure includes a sound guiding tube and an acoustic cavity. The acoustic cavity is in acoustic communication with the acoustoelectric transducer, and is in acoustic communication with outside of the microphone through the sound guiding tube. The acoustic structure has a first resonance frequency, the acoustoelectric transducer has a second resonance frequency, and an absolute value of a difference between the first resonance frequency and the second resonance frequency is not less than 100 Hz. By disposing different acoustic structures, resonance peaks in different frequency ranges may be added to the microphone, which improves a sensitivity of the microphone near multiple resonance peaks, thereby improving a sensitivity of the microphone in the entire wide frequency band.
1. A microphone, comprising:
at least one acoustoelectric transducer configured to convert a sound signal to an electrical signal; and
an acoustic structure including a sound guiding tube and an acoustic cavity, the acoustic cavity being in acoustic communication with the at least one acoustoelectric transducer, wherein,
the acoustic structure has a first resonance frequency, the at least one acoustoelectric transducer has a second resonance frequency, and an absolute value of a difference between the first resonance frequency and the second resonance frequency is not less than 100 Hz, wherein the microphone further includes a second acoustic structure including a second sound guiding tube and a second acoustic cavity, the acoustic cavity is in acoustic communication with the second acoustic cavity through the sound guiding tube, the second acoustic cavity is in acoustic communication with the outside of the microphone through the second sound guiding tube, the second acoustic structure has a third resonance frequency that is different from the first resonance frequency, and a difference between the first resonance frequency and the third resonance frequency is less than 100 Hz.
2. The microphone of claim 1 , wherein a sensitivity of response of the microphone at the first resonance frequency is greater than a sensitivity of response of the at least one acoustoelectric transducer at the first resonance frequency.
3. The microphone of claim 1 , wherein the first resonance frequency is related to one or more structural parameters of the acoustic structure, and the one or more structural parameters of the acoustic structure include at least one of a shape of the sound guiding tube, a size of the sound guiding tube, a size of the acoustic cavity, an acoustic resistance of the sound guiding tube or the acoustic cavity, or a roughness of an inner surface of a side wall forming the sound guiding tube.
4. The microphone of claim 1 , further comprising:
a housing, wherein the at least one acoustoelectric transducer and the acoustic cavity are located within the housing, and the housing includes a first side wall for forming the acoustic cavity.
5. The microphone of claim 4 , wherein a first end of the sound guiding tube is located on the first side wall, and a second end of the sound guiding tube is away from the first side wall and is located outside the housing.
6. The microphone of claim 4 , wherein a first end of the sound guiding tube is located on the first side wall, and a second end of the sound guiding tube is away from the first side wall and extends into the acoustic cavity.
7. The microphone of claim 4 , wherein a first end of the sound guiding tube is away from the first side wall and is located outside the housing, and a second end of the sound guiding tube extends into the acoustic cavity.
8. The microphone of claim 1 , wherein an acoustic resistance structure is disposed in the sound guiding tube or the acoustic cavity, and the acoustic resistance structure is configured to adjust a frequency bandwidth of the acoustic structure.
9. The microphone of claim 8 , wherein an acoustic resistance value of the acoustic resistance structure is in a range from 1 MKS Rayls to 100 MKS Rayls.
10. The microphone of claim 8 , wherein a thickness of the acoustic resistance structure is in a range from 20 μm to 300 μm, an aperture size of the acoustic resistance structure is in a range from 20 μm to 300 μm, and/or a porosity of the acoustic resistance structure is in a range from 30% to 50%.
11. The microphone of claim 8 , wherein the acoustic resistance structure is disposed at one or more of positions including: an outer surface of a side wall forming the sound guiding tube and away from a first side wall, a position inside the sound guiding tube, an inner surface of the first side wall, a position inside the acoustic cavity, an inner surface of a second side wall forming a hole portion of the at least one acoustoelectric transducer, an outer surface of the second side wall, a position inside the hole portion of the at least one acoustoelectric transducer.
12. The microphone of claim 1 , wherein an aperture size of the sound guiding tube is not greater than twice a length of the sound guiding tube, the aperture size of the sound guiding tube is in a range from 0.1 mm to 10 mm, and the length of the sound guiding tube is in a range from 1 mm to 8 mm.
13. The microphone of claim 1 , wherein an inner diameter of the acoustic cavity is not less than a thickness of the acoustic cavity, the inner diameter of the acoustic cavity is in a range from 1 mm to 20 mm, and a thickness of the acoustic cavity is in a range from 1 mm to 20 mm.
14. The microphone of claim 1 , wherein:
when the third resonance frequency is greater than the first resonance frequency, a difference between a sensitivity of response of the microphone at the third resonance frequency and a sensitivity of response of the at least one acoustoelectric transducer at the third resonance frequency is greater than a difference between a sensitivity of response of the microphone at the first resonance frequency and a sensitivity of response of the at least one acoustoelectric transducer at the first resonance frequency.
15. The microphone of claim 1 , wherein the second acoustic cavity is in acoustic communication with the acoustic cavity through the sound guiding tube.
16. The microphone of claim 1 , wherein the at least one acoustoelectric transducer further includes a second acoustoelectric transducer, the second acoustic cavity being in acoustic communication with the second acoustoelectric transducer.
17. A microphone, comprising:
at least one acoustoelectric transducer configured to convert a sound signal to an electrical signal; and
an acoustic structure including a sound guiding tube and an acoustic cavity, the acoustic cavity being in acoustic communication with an outside of the microphone through the sound guiding tube;
a second acoustic structure including a second sound guiding tube and a second acoustic cavity, the second acoustic cavity being in acoustic communication with the outside of the microphone through the second sound guiding tube; and
a third acoustic structure including a third sound guiding tube, a fourth sound guiding tube, and a third acoustic cavity, wherein:
the acoustic cavity is in acoustic communication with the third acoustic cavity through the third sound guiding tube,
the second acoustic cavity is in acoustic communication with the third acoustic cavity through the fourth sound guiding tube,
the third acoustic cavity is in acoustic communication with the at least one acoustoelectric transducer, and
the acoustic structure has a first resonance frequency, the at least one acoustoelectric transducer has a second resonance frequency, and an absolute value of a difference between the first resonance frequency and the second resonance frequency is not less than 100 Hz; the second acoustic structure has a third resonance frequency that is different from the first resonance frequency, the third acoustic structure has a fourth resonance frequency that is different from the third resonance frequency and the first resonance frequency.
18. The microphone of claim 1 , wherein the at least one acoustoelectric transducer includes a hole portion, and the acoustic structure is acoustically connected to the acoustoelectric transducer through the hole portion.