US3887787A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dry process photographic paper recording apparatus
Assignee: Del Mar Engineering Laboratories
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Filing: 1974-10-03
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Granted: 1975-06-03
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Expires: 1994-10-03
Abstract
Abstract Apparatus is provided for using a dry process photographic medium of the type described in Copending application Ser. No. 510,153 for recording data. The photographic medium includes an electrically conductive base which responds to electric power to produce developing heat internally. The apparatus of the invention includes electrodes in the form of rods, or rollers, for example, across which the medium is drawn, and electronic circuitry connected to the electrodes for introducing a controlled electric current flow through the base of the medium between the electrodes to develop latent images previously exposed on the medium, by the generation of electric power directly in the base.
Inventors
- 👤 David Paul Gregg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:34
CPC Classifications
G; G03; G03D; G03D13/00; G03D13/002; G05; G05F; G05F1/00; G05F1/66
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
79 words
Apparatus for developing a dry process photographic web, said web comprising a base of electrically conductive material and a light sensitive photographic emulsion on the base formed of materials capable of being developed by heat, said apparatus including: electrode means across which the web is drawn, and electrical circuit means connected to said electrode means for producing an electric power dissipation within the base of the web to cause internal developing heat to be generated thereby for the emulsion.
Claim 2
Dependent Claim
79 words
Apparatus for developing a dry process photographic web, said web comprising a base of electrically conductive material and a light sensitive photographic emulsion on the base formed of materials capable of being developed by heat, said apparatus including: electrode means across which the web is drawn, and electrical circuit means connected to said electrode means for producing an electric power dissipation within the base of the web to cause internal developing heat to be generated thereby for the emulsion.
Claim 3
Dependent Claim
79 words
Apparatus for developing a dry process photographic web, said web comprising a base of electrically conductive material and a light sensitive photographic emulsion on the base formed of materials capable of being developed by heat, said apparatus including: electrode means across which the web is drawn, and electrical circuit means connected to said electrode means for producing an electric power dissipation within the base of the web to cause internal developing heat to be generated thereby for the emulsion.
Claim 4
Dependent Claim
79 words
Apparatus for developing a dry process photographic web, said web comprising a base of electrically conductive material and a light sensitive photographic emulsion on the base formed of materials capable of being developed by heat, said apparatus including: electrode means across which the web is drawn, and electrical circuit means connected to said electrode means for producing an electric power dissipation within the base of the web to cause internal developing heat to be generated thereby for the emulsion.
Claim 5
Dependent Claim
50 words
The apparatus defined in claim 1, in which said electrode means comprises first and second elongated electrically conductive elements spaced from one another, and in which said electrical circuit means is connected to said elements to produce an electric power dissipation within the portion of the web between the elements.
Claim 6
Dependent Claim
17 words
The apparatus defined in claim 2, in which the elongated elements are in the form of rollers.
Claim 7
Dependent Claim
44 words
The apparatus defined in claim 1, in which said electrical circuit means includes regulating means for maintaining an essentially constant dissipation of said electric power within the base of the web for a particular speed of said web and for a particular ambient temperature.
Claim 8
Dependent Claim
41 words
The apparatus defined in claim 1, in which said electrical circuit means includes regulating means for changing the rate of dissipation of electric power in the base of the web for changes in web speed and for changes in ambient temperature.
Claim 9
Dependent Claim
56 words
The apparatus defined in claim 1, and which includes further electrode means spaced from said first-named electrode means, and further electrical circuit means connected to said further electrode means for producing an electric dissipation within a further portion of the base of the web to cause internal emulsion-developing heat to be generated in said further portion.
Claim 10
Dependent Claim
68 words
The apparatus defined in claim 2, in which said electrode means comprises a third electrically conductive element spaced from said first and second elements, and further electrical circuitry connected to said second and third elements for producing an electric power dissipation within the portion of the web between said second and third elements to cause internal emulsion-developing heat to be generated in said last-named portion of the web.
Claim 11
Dependent Claim
60 words
The apparatus defined in claim 7, and which includes optical density detecting means optically coupled to the portion of said web between said second and third elements, and control circuitry connecting said optical density detecting means into circuit with said further electrical circuitry to cause the Development of said further portion of the web to reach a predetermined optical density.
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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |