Invalidity dossier
US 6975736
Microphone
Current assignee: Panasonic Holdings Corp
Added 9/23/2026, 4:04:33 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 6,975,736 B2
Title: Microphone
Inventor: Akinori Hasegawa
Original Assignee: Matsushita Electric Industrial Co., Ltd. (current assignee listed as Panasonic Holdings Corp.)
Application No.: US 10/487,080; U.S. National Phase of PCT/JP03/08271
Priority Date: 2002-07-19 · Filed: 2003-06-30 · Granted/Published: 2005-12-13
Status (as listed): Expired – Lifetime (anticipated expiration 2023-06-30)
Purpose: Conventional microphones placed the case opening directly facing the diaphragm; under excessive sound pressure the deformed diaphragm touched the back plate, stopping vibration and causing distortion. The invention aims to provide a microphone that does not produce distortion even when excessive sound pressure is applied.
Plain-language scope: A microphone houses a diaphragm, a back plate parallel to it with a fixed gap, a support holding both, and a mechanoelectric transducer coupled to the back plate, all inside a case. The diaphragm has a first face and a second face and divides the case interior into a first space touching the first face and a second space touching the second face; the back plate sits in the second space, and the case has a through hole opening into the second space — i.e., on a side that does not directly face the diaphragm. Because the diaphragm acts as the boundary surface, the confined air space is smaller than in the conventional arrangement, raising mechanical resistance, lowering sensitivity to excessive sound pressure, and suppressing distortion. In an alternative embodiment the hole is on a side intersecting the diaphragm at right angles, which also helps prevent sensitivity changes when the hole is blocked by an adjacent printed circuit board during mounting.
Source: https://patents.google.com/patent/US6975736/en
What the excerpt does not establish: The supplied text gives no claim set, no named prior-art references, no figures' visual details beyond captions and descriptions, no claim of critical dimensions or materials beyond "mechanoelectric transducer formed of a semiconductor device," and no legal conclusions on validity, enforceability, or scope of the listed status. It also does not state why the application was a national-phase filing or any prosecution history.
Generated 10/1/2026, 9:51:10 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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