US4740815A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for compensating for irregularities of illumination for a copier
Assignee: Ricoh Co Ltd
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Filing: 1987-07-07
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Granted: 1988-04-26
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Expires: 2007-07-07
Abstract
Abstract An apparatus for automatically compensating for irregularities of illumination on a photoconductive element of a slit exposure type copier in which a lens is selectively movable along its optical axis and perpendicularly thereto. The apparatus has a simple construction.
Inventors
- 👤 Ichiro Tsuruoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:32
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/04; G03G15/041; G03B; G03B27/00; G03B27/32; G03B27/52; G03B27/54; G03B27/542; G03G15/0415
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
185 words
An apparatus for compensating for irregularities of illumination in a slit exposure type copier in which a lens is selectively movable along and perpendicularly to an optical axis of said lens, comprising: two shield plates rotatably supported by a bracket which is mounted on a lens holder which is movable integrally with the lens, angular positions of said shield plates being individually variable to vary a range over which a beam is shielded and, thereby, an illumination distribution on a photoconductive element; a first cam movable along the optical axis of the lens in synchronism with a movement of said lens along said optical axis, said first cam having a cam surface which changes the angular positions of the shield plates in response to a movement of said shield plates which is perpendicular to the optical axis of the lens; and second cams each having a cam surface which changes a position of the first cam in an up-down direction with respect to the optical axis of the lens in response to the movement of the first cam along said optical axis of the lens.
Claim 2
Independent Claim
185 words
An apparatus for compensating for irregularities of illumination in a slit exposure type copier in which a lens is selectively movable along and perpendicularly to an optical axis of said lens, comprising: two shield plates rotatably supported by a bracket which is mounted on a lens holder which is movable integrally with the lens, angular positions of said shield plates being individually variable to vary a range over which a beam is shielded and, thereby, an illumination distribution on a photoconductive element; a first cam movable along the optical axis of the lens in synchronism with a movement of said lens along said optical axis, said first cam having a cam surface which changes the angular positions of the shield plates in response to a movement of said shield plates which is perpendicular to the optical axis of the lens; and second cams each having a cam surface which changes a position of the first cam in an up-down direction with respect to the optical axis of the lens in response to the movement of the first cam along said optical axis of the lens.
References Cited (Backward Citations)
US4582418A
Cited
US4641957A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-26 | 1991-10-26 | 1992-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-26 | 1995-10-26 | 1996-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-26 | 1999-10-26 | 2000-04-26 | $7700.00 | Window Closed / Lapsed |