US4559418A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceramic microphone
Assignee: PRIMO CO Ltd
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Filing: 1983-10-05
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Granted: 1985-12-17
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Expires: 2003-10-05
Abstract
Abstract A ceramic microphone is described which comprises a diaphragm for receiving sound waves, a thin ceramic plate attached to the diaphragm for transducing the sound waves to electric signals, and a plurality of electrodes on each of the opposite sides of the ceramic plate, the plurality of electrodes being polarized so that each of a pair of the electrodes faced across the ceramic plate forms a capacitor and the opposite-polarity electrodes of each of the capacitors are serially connected each other.
Inventors
- 👤 Nobuomi Imai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:56
CPC Classifications
H; H04; H04R; H04R17/00; H04R17/02
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
108 words
A ceramic microphone comprising; a diaphragm for receiving sound waves; a thin ceramic plate attached to said diaphragm for transducing said sound waves to electric signals; electrode means for taking out the transduced electric signals, said electrode means comprising a plurality of electrodes on each of the opposite sides of said ceramic plate, said plurality of electrodes being polarized so that each of a pair of said electrodes faced across said ceramic plate forms a capacitor and the opposite-polarity electrodes of each of said capacitors are serially connected to each other; and a FET amplifying circuit connected to said electrode means an in a casing of the microphone.
Claim 2
Dependent Claim
108 words
A ceramic microphone comprising; a diaphragm for receiving sound waves; a thin ceramic plate attached to said diaphragm for transducing said sound waves to electric signals; electrode means for taking out the transduced electric signals, said electrode means comprising a plurality of electrodes on each of the opposite sides of said ceramic plate, said plurality of electrodes being polarized so that each of a pair of said electrodes faced across said ceramic plate forms a capacitor and the opposite-polarity electrodes of each of said capacitors are serially connected to each other; and a FET amplifying circuit connected to said electrode means an in a casing of the microphone.
Claim 3
Dependent Claim
28 words
The ceramic microphone of claim 1 wherein said FET amplifying circuit is in the form of an integrated circuit and is attached to the edge of said diaphragm.
Claim 4
Dependent Claim
176 words
A ceramic microphone comprising: diaphragm means for receiving sound waves; ceramic plate means attached to said diaphragm means for transducing said sound waves; electrode means for converting said transduced sound waves to electrical signals, comprising: (a) a plurality of sub-electrodes of identical size, shape and area; (b) each said sub-electrodes attached to said ceramic plate means in such a way that the majority of the surface area of said sub-electrode is overlapping another sub-electrode on the reverse side of said ceramic plate to form an electrode capacitor, said another sub-electrode being of opposite polarity to said each sub-electrode; (c) said each sub-electrode also being of opposite polarity to adjacent sub-electrodes on the same side of said ceramic plate; internal FET amplification means for amplifying said electrical signals from said electrode means, said FET amplifying circuit being an integrated circuit attached to said diaphragm means; and terminal means for serially connecting said electrode capacitors to said FET amplification means, said terminal means connecting each said sub-electrode to one of an adjacent sub-electrode and said FET amplification means.
Claim 5
Dependent Claim
176 words
A ceramic microphone comprising: diaphragm means for receiving sound waves; ceramic plate means attached to said diaphragm means for transducing said sound waves; electrode means for converting said transduced sound waves to electrical signals, comprising: (a) a plurality of sub-electrodes of identical size, shape and area; (b) each said sub-electrodes attached to said ceramic plate means in such a way that the majority of the surface area of said sub-electrode is overlapping another sub-electrode on the reverse side of said ceramic plate to form an electrode capacitor, said another sub-electrode being of opposite polarity to said each sub-electrode; (c) said each sub-electrode also being of opposite polarity to adjacent sub-electrodes on the same side of said ceramic plate; internal FET amplification means for amplifying said electrical signals from said electrode means, said FET amplifying circuit being an integrated circuit attached to said diaphragm means; and terminal means for serially connecting said electrode capacitors to said FET amplification means, said terminal means connecting each said sub-electrode to one of an adjacent sub-electrode and said FET amplification means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-16 | 1989-06-17 | 1989-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-16 | 1993-06-17 | 1993-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-16 | 1997-06-17 | 1997-12-17 | $7700.00 | Window Closed / Lapsed |