US4072414A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screen for an electrophotographic printing machine
Assignee: Xerox Corp
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Filing: 1976-10-29
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Granted: 1978-02-07
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Expires: 1996-10-29
Abstract
Abstract An electrophotographic printing machine in which a transparency light image is projected through a screen having a plurality of opaque regions. At least a portion of the opaque regions have a light reflecting surface on one side thereof and a light absorbing surface on the other side thereof. The screen is positioned so that the light reflecting surfaces of the opaque regions form a visual image of the transparency light image being projected therethrough. Incident light rays are absorbed by the absorbing surfaces of the opaque regions.
Inventors
- 👤 William J. Hanson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:22
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/04; G03G15/04027
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
125 words
An electrophotographic printing machine for reproducing a transparency, including: a photoconductive member; means for charging at least a portion of said photoconductive member to a substantially uniform level; a screen member comprising a plurality of opaque regions with at least a portion thereof having a light reflecting surface on one side thereof and a light absorbing surface on the other side thereof; and means for projecting a light image of the transparency through said screen member onto the charged portion of said photoconductive member to record thereon a modulated electrostatic latent image, said screen member being positioned so that the reflecting surfaces of the opaque regions form a visual image of the transparency and the absorbing surfaces of the opaque regions absorb incident light rays.
Claim 2
Dependent Claim
125 words
An electrophotographic printing machine for reproducing a transparency, including: a photoconductive member; means for charging at least a portion of said photoconductive member to a substantially uniform level; a screen member comprising a plurality of opaque regions with at least a portion thereof having a light reflecting surface on one side thereof and a light absorbing surface on the other side thereof; and means for projecting a light image of the transparency through said screen member onto the charged portion of said photoconductive member to record thereon a modulated electrostatic latent image, said screen member being positioned so that the reflecting surfaces of the opaque regions form a visual image of the transparency and the absorbing surfaces of the opaque regions absorb incident light rays.
Claim 3
Dependent Claim
36 words
A printing machine as recited in claim 1, further including: a field lens in a light receiving relationship with the light image of the transparency; and means for supporting said field lens and said screen member.
Claim 4
Dependent Claim
22 words
A printing machine as recited in claim 2, wherein said supporting means includes a substantially transparent platen spaced from said photoconductive member.
Claim 5
Dependent Claim
21 words
A printing machine as recited in claim 3, wherein said field lens is interposed between said platen and said screen member.
Claim 6
Dependent Claim
21 words
A printing machine as recited in claim 3, wherein said screen member is interposed between said platen and said field lens.
Claim 7
Dependent Claim
55 words
A printing machine as recited in claim 3, further including: a composition frame disposed on said platen; and means for exposing the charged portion of said photoconductive member to a light image of said composition frame recording thereon a combined electrostatic latent image of the transparency and the electrostatic latent image of said composition frame.
Claim 8
Dependent Claim
44 words
A printing machine as recited in claim 6 wherein said exposing means includes: a light source arranged to illuminate said composition frame; and a lens positioned to receive at least the light rays transmitted from said composition frame to form a light image thereof.
Claim 9
Dependent Claim
32 words
A printing machine as recited in claim 6, wherein said screen member includes a transparent substrate with the opaque region thereof being a plurality of spaced dots disposed on said transparent substrate.
Claim 10
Dependent Claim
16 words
A printing machine as recited in claim 8, wherein said projecting means includes a slide projector.
Claim 11
Dependent Claim
111 words
A printing machine as recited in claim 9, further including: means for filtering the light image of the transparency to form a single color light image which irradiates the charged portion of said photoconductive member to record thereon a single color electrostatic latent image; means for developing the single color electrostatic latent image recorded on said photoconductive member with toner particles complementary in color to the color of the single color light image; means for transferring the toner powder image from the electrostatic latent image recorded on said photoconductive member to a sheet of support material; and means for permanently affixing the toner powder image to the sheet of support material.
Claim 12
Dependent Claim
53 words
A screen for use in an electrophotographic printing machine, including: a substantially transparent member; and a plurality of opaque regions disposed on said transparent member with at least a portion of said opaque regions having a light reflecting surface on one side thereof and a light absorbing surface on the other side thereof.
Claim 13
Dependent Claim
53 words
A screen for use in an electrophotographic printing machine, including: a substantially transparent member; and a plurality of opaque regions disposed on said transparent member with at least a portion of said opaque regions having a light reflecting surface on one side thereof and a light absorbing surface on the other side thereof.
Claim 14
Dependent Claim
16 words
A screen as recited in claim 11, wherein said opaque regions include a plurality of dots.
Claim 15
Dependent Claim
27 words
A screen as recited in claim 12, wherein the light reflecting surface of said dots is white and the light absorbing surface of said dots is black.
Claim 16
Dependent Claim
21 words
A screen as recited in claim 13, wherein the white surface of said dots contacts one surface of said transparent member.
Claim 17
Dependent Claim
22 words
A screen as recited in claim 14, wherein said dots are arranged in a substantially equally spaced array on said transparent member.
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) | 1981-02-06 | 1981-08-08 | 1982-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-06 | 1985-08-08 | 1986-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-06 | 1989-08-08 | 1990-02-07 | $7700.00 | Window Closed / Lapsed |