US 11,902,742 B2
Microphone chip, microphone, and terminal device
Dongming Fang, Shenzhen (CN); and Ming Li, Shenzhen (CN)
Assigned to Huawei Technologies Co., Ltd., Shenzhen (CN)
Filed by HUAWEI TECHNOLOGIES CO., LTD., Guangdong (CN)
Filed on Feb. 25, 2022, as Appl. No. 17/681,285.
Application 17/681,285 is a continuation of application No. PCT/CN2020/095940, filed on Jun. 12, 2020.
Claims priority of application No. 201910817689.X (CN), filed on Aug. 30, 2019.
Prior Publication US 2022/0182771 A1, Jun. 9, 2022
Int. Cl. H04R 23/00 (2006.01); G01H 9/00 (2006.01); G02F 1/125 (2006.01)
CPC H04R 23/008 (2013.01) [G01H 9/004 (2013.01); G02F 1/125 (2013.01); H04R 2410/03 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A microphone chip, wherein the microphone chip comprises:
a substrate and a diaphragm that are disposed oppositely;
a reflector located on a side of the diaphragm and that is close to the substrate;
a grating group located between the substrate and the diaphragm; and
an optical emitter and an optical detector that are located between the substrate and the grating group, wherein
the grating group comprises a plurality of gratings, and distances between at least two gratings in the plurality of gratings and the reflector are different, wherein a difference g between the distances between the at least two gratings in the plurality of gratings and the reflector satisfies:
(2n−1)×λ/8−λ/16≤g≤(2n−1)×λ/8+λ/16, wherein λ is a wavelength of light emitted by the optical emitter, and n is an integer greater than 0.