Acoustic converter and microphone

Abstract

To alleviate stress concentration during collision between the thin film and the backplate, thereby suppressing damage to both the thin film and the backplate. [Solution] The acoustic converter 100 comprises a substrate 10 having a cavity 11, a thin film 20 disposed to cover the cavity 11, and a back plate 30 facing the thin film 20 in the thickness direction of the substrate 10, positioned on the opposite side of the substrate 10 from the thin film, and having a plurality of holes 31 formed therein. The plurality of holes 31 have first holes 31A and second holes 31B aligned in the X-axis direction when viewed in the thickness direction of the substrate 10. The back plate 30 has a main plate 32 having a plurality of holes 31 formed therein and facing the thin film 20, and a protruding portion 60 projecting from the main plate 32 toward the thin film 20. The protruding portion 60 is formed between the first hole 31A and the second hole 31B, along a part of the periphery of the first hole 31A.

Claims

1. A substrate having a cavity, A thin film arranged to cover the cavity, The substrate comprises a back plate that faces the thin film in the thickness direction of the substrate, is positioned on the opposite side of the substrate from the thin film, and has a plurality of holes formed on it, The plurality of holes are, The substrate has first holes and second holes aligned in the first direction when viewed in the thickness direction of the substrate, The aforementioned backplate is The aforementioned plurality of holes are formed in the main body plate facing the thin film, It has a protruding portion that extends from the main body plate toward the thin film, The aforementioned protrusion is An acoustic conversion device formed between the first hole and the second hole, along a portion of the periphery of the first hole.

2. The acoustic conversion device according to claim 1, wherein the protruding portion is formed to surround the first hole when viewed in the thickness direction of the substrate.

3. The acoustic conversion device according to claim 1 or 2, wherein the plurality of holes are arranged in a honeycomb pattern when viewed in the thickness direction of the substrate.

4. The plurality of holes are arranged in a plurality of rows in the first direction, The acoustic conversion device according to claim 1, wherein the plurality of rows are arranged in a second direction intersecting the first direction.

5. The acoustic conversion device according to claim 1, wherein the plurality of holes are arranged in a staggered pattern.

6. The acoustic conversion device according to claim 4 or 5, wherein the plurality of holes are formed to form a circle when viewed in the thickness direction of the substrate.

7. The acoustic conversion device according to claim 4 or 5, wherein the plurality of holes are formed to form a polygon when viewed in the thickness direction of the substrate.

8. The sound conversion device described in claim 1 or 2, A microphone comprising a circuit section that outputs the signal output from the aforementioned sound converter to the outside.

9. A housing having an opening and housing the sound conversion device, The enclosure further comprises a bottom plate that closes the opening of the enclosure, The housing or the bottom plate has through holes that penetrate in the thickness direction of the substrate and communicate with the cavity. Inside the aforementioned housing, The first space is the space between the thin film and the housing or the bottom plate in which the through hole is formed, The microphone according to claim 8, wherein a second space is formed between the thin film and the housing or bottom plate in which the through hole is not formed.

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