US3830645A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for creating an electrostatic latent image by charge modulation
Assignee: Pitney Bowes Inc
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Filing: 1972-09-01
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Granted: 1974-08-20
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Expires: 1992-09-01
Abstract
Abstract A transparent dielectric film is juxtaposed with the electrostatically charged surface of a photoconductive member. An optical image is projected onto the photoconductive member to create a corresponding first electrostatic latent image on the photoconductive member surface. The exposed dielectric film surface is charged by an AC scorotron; the first electrostatic latent image acting to modulate the charge deposition such as to produce a zero potential at the exposed film surface. The photoconductive member is flooded with light to dissipate the first electrostatic latent image, rendering the charge deposition on the exposed film surface effective as a second corresponding electrostatic latent image for ultimate development and image transfer to plain paper.
Inventors
- 👤 G Zweig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:37
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; G03G15/226; G03G15/227; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/102
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
59 words
The method defined in claim 1, wherein the placing step includes convergently moving the charged surface of the photoconductive member into contact with said one surface of the dielectric film, and said subjecting step subjects the other film surface to AC electrostatic charge deposition effective to establish a substantially zero electric potential plane adjacent to the other film surface.
Claim 2
Dependent Claim
24 words
The method defined in claim 1, wherein said dissipating step comprises flooding the member with the light to dissipate the first electrostatic latent image.
Claim 3
Dependent Claim
41 words
The method defined in claim 1, which further includes the steps of: A. after said developing step, separating the dielectric film from the photoconductive member; and B. transferring the developer in image form from the other film surface to plain paper.
Claim 4
Dependent Claim
33 words
The method defined in claim 4, which further includes the steps of: A. recharging the photoconductor member surface; and B. after said transferring step, removing residual developer and electrostatic charges from the film.
Claim 5
Dependent Claim
51 words
The method defined in claim 2, wherein the dielectric film is optically transparent to permit the member to be exposed to the optical image through the film and to permit the first electrostatic latent image thereby formed on the meMber to be thereafter dissipated by exposure to light through the film.
Claim 6
Independent Claim
226 words
A method for creating a developable electrostatic latent image on a surface of a non-photoconductive insulating member comprising the steps of: A. uniformly electrostatically charging a surface of a photoconductive insulating member to a DC potential; then B. placing the non-photoconductive insulating member over the photoconductive insulating member in its charged state so as to dispose one of the surfaces of the non-photoconductive member in virtual physical contact with the previously uniformly charged surface of the photoconductive member; and thereafter C. exposing the charged surface of the photoconductive insulating member to an optical image effective to create on said surface of the photoconductive member an intermediate electrostatic latent image corresponding to the optical image; D. subjecting the other surface of the non-photoconductive insulating member to charge from an AC electrostatic charging source, the electrostatic influence of the intermediate electrostatic latent image acting to modulate the charge deposition on the other surface of the non-photoconductive member so as to produce a substantially zero electric potential plane adjacent to the other surface of the non-photoconductive insulating member; and E. dissipating the intermediate electrostatic latent image so as to eliminate the electrostatic influence thereof on the modulated charge deposited on the other surface of the non-photoconductive insulating member to render the modulated charge deposition effective to be developed as a final electrostatic latent image corresponding to said optical image.
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) | 1977-08-19 | 1978-02-18 | 1978-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-19 | 1982-02-18 | 1982-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-19 | 1986-02-18 | 1986-08-20 | $7700.00 | Window Closed / Lapsed |