US4070741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making an electret acoustic transducer
Assignee: Bank of New England NA
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Filing: 1977-04-18
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Granted: 1978-01-31
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Expires: 1997-04-18
Abstract
Abstract In the method of construction disclosed herein, posts for supporting the condenser transducer diaphragm in relation to a backplate are formed on the diaphragm film itself by selectively etching away a photoresist material laminated to the film. The electret material is then supported on the backplate rather than being carried by the diaphragm.
Inventors
- 👤 Svetislav V. Djuric
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:23
CPC Classifications
H; H04; H04R; H04R31/00; H04R31/003; H04R19/00; H04R19/01; H04R19/016; Y; Y10; Y10T; Y10T29/00; Y10T29/43; Y10T29/435; Y10T29/49; Y10T29/49002; Y10T29/49005; Y10T29/49226
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
108 words
The method of making an electret acoustic transducer comprising: laminating an elastic diaphragmatic plastic film with a layer of material of predetermined thickness; selectively removing undesired portions of said layer of material, leaving a desired post pattern on the film; metalizing the post side of said film to render it conductive; securing said film to a supporting ring; providing a conductive backplate carrying on one face thereof a layer of polarized electret material which is itself insulating; mounting said backplate and said ring in juxtaposition in a transducer assembly with said post pattern contacting the electret layer, the diaphragmatic film being deformed and spaced from the backplate thereby.
Claim 2
Independent Claim
108 words
The method of making an electret acoustic transducer comprising: laminating an elastic diaphragmatic plastic film with a layer of material of predetermined thickness; selectively removing undesired portions of said layer of material, leaving a desired post pattern on the film; metalizing the post side of said film to render it conductive; securing said film to a supporting ring; providing a conductive backplate carrying on one face thereof a layer of polarized electret material which is itself insulating; mounting said backplate and said ring in juxtaposition in a transducer assembly with said post pattern contacting the electret layer, the diaphragmatic film being deformed and spaced from the backplate thereby.
Claim 3
Independent Claim
121 words
The method of making an electret acoustic transducer comprising: laminating an elastic diaphragmatic plastic film with a photoresist material; exposing said material in a pattern corresponding to a desired post pattern for supporting a diaphragm in the transducer; removing the undesired portion of said material, leaving the desired post pattern on the film; metalizing the post side of said film to render it conductive; securing said film to a supporting ring; providing a conductive backplate carrying on one face thereof a layer of polarized electret material which is itself insulating; mounting said backplate and said ring in juxtaposition in a transducer assembly with said post pattern contacting the electret layer, the diaphragmatic film being deformed and spaced from the backplate thereby.
Claim 4
Independent Claim
121 words
The method of making an electret acoustic transducer comprising: laminating an elastic diaphragmatic plastic film with a photoresist material; exposing said material in a pattern corresponding to a desired post pattern for supporting a diaphragm in the transducer; removing the undesired portion of said material, leaving the desired post pattern on the film; metalizing the post side of said film to render it conductive; securing said film to a supporting ring; providing a conductive backplate carrying on one face thereof a layer of polarized electret material which is itself insulating; mounting said backplate and said ring in juxtaposition in a transducer assembly with said post pattern contacting the electret layer, the diaphragmatic film being deformed and spaced from the backplate thereby.
Claim 5
Dependent Claim
23 words
The method as set forh in claim 2 wherein said supporting post pattern comprises a circular post in the center of said ring.
Claim 6
Dependent Claim
23 words
The method as set forth in claim 2 wherein said supporting post pattern comprises a circular array of posts concentric with said ring.
Claim 7
Dependent Claim
33 words
The method as set forth in claim 2 wherein said photoresist material comprises a copper foil and a photosensitive resist material and wherein the undesired portions of the copper are removed by etching.
Claim 8
Dependent Claim
14 words
The method as set forth in claim 2 wherein said electret material is polytetrafluoroethylene.
Claim 9
Independent Claim
126 words
The method of making an electret acoustic transducer comprising: vacuum depositing a thin copper layer over a plastic film and laminating it with a photosensitive polymer resist; exposing said resist in a pattern corresponding to a desired post pattern for supporting a diaphragm in the transducer; removing the undesired portion of said resist, leaving resist in the desired post pattern on the film; metalizing the post side of said film to render it conductive; securing said film to a supporting ring; providing a conductive backplate carrying on one face thereof a layer of polarized Teflon electret material; mounting said backplate and said ring in juxtaposition in a transducer assembly with said post pattern contacting the electret layer, the diaphragmatic film being spaced from the backplate thereby.
Claim 10
Independent Claim
126 words
The method of making an electret acoustic transducer comprising: vacuum depositing a thin copper layer over a plastic film and laminating it with a photosensitive polymer resist; exposing said resist in a pattern corresponding to a desired post pattern for supporting a diaphragm in the transducer; removing the undesired portion of said resist, leaving resist in the desired post pattern on the film; metalizing the post side of said film to render it conductive; securing said film to a supporting ring; providing a conductive backplate carrying on one face thereof a layer of polarized Teflon electret material; mounting said backplate and said ring in juxtaposition in a transducer assembly with said post pattern contacting the electret layer, the diaphragmatic film being spaced from the backplate thereby.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-30 | 1981-08-01 | 1982-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-30 | 1985-08-01 | 1986-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-30 | 1989-08-01 | 1990-01-31 | $7700.00 | Window Closed / Lapsed |