US4914458A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image forming apparatus
Assignee: Ricoh Co Ltd
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Filing: 1988-09-21
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Granted: 1990-04-03
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Expires: 2008-09-21
Abstract
Abstract An image forming apparatus forms a recorded image of an original image on a recording sheet by an electrophotography method. An optical scanning unit emits a laser beam which scans a surface of a photosensitive drum. The image forming apparatus is provided with a light absorbing member for absorbing the laser beam which is reflected by the surface of the photosensitive drum so as to prevent a flare from being generated.
Inventors
- 👤 Hiroshi Mori
- 👤 Yoichiro Sugino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:36
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/435; B41J2/44; B41J2/442; G; G03; G03G; G03G15/00; G03G15/04; G03G15/04036; G03G15/04045; G03G15/04072; G03G15/22; G03G15/32; G03G15/326
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
143 words
An image forming apparatus which forms a recorded image of an original image on a recording sheet by an electrophotography method, said image forming apparatus comprising: a photosensitive body; scanning means for scanning a surface of said photosensitive body by a laser beam modulated depending on the original image so as to form an electrostatic image of the original image on the surface of said photosensitive body; transfer means for transferring and fixing the electrostatic image on the surface of said photosensitive body onto the recording sheet; and light absorbing means located at a position confronting the surface of said photosensitive body for substantially absorbing the laser beam which is reflected by the surface of said photosensitive body to keep the laser beam reflected by the surface of said photosensitive body from causing a secondary exposure on the surface of said photosensitive body.
Claim 2
Dependent Claim
143 words
An image forming apparatus which forms a recorded image of an original image on a recording sheet by an electrophotography method, said image forming apparatus comprising: a photosensitive body; scanning means for scanning a surface of said photosensitive body by a laser beam modulated depending on the original image so as to form an electrostatic image of the original image on the surface of said photosensitive body; transfer means for transferring and fixing the electrostatic image on the surface of said photosensitive body onto the recording sheet; and light absorbing means located at a position confronting the surface of said photosensitive body for substantially absorbing the laser beam which is reflected by the surface of said photosensitive body to keep the laser beam reflected by the surface of said photosensitive body from causing a secondary exposure on the surface of said photosensitive body.
Claim 3
Dependent Claim
107 words
An image forming apparatus as claimed in claim 1, in which said photosensitive body comprises a rotatable photosensitive drum, and said optical scanning means scans a surface of said photosensitive drum in a main scanning direction along a longitudinal direction of said photosensitive drum and in a sub scanning direction as said photosensitive drum rotates, said optical scanning means emitting the laser beam with a predetermined incident angle with respect to the surface of said photosensitive drum so that the laser beam reflected by the surface of said photosensitive drum travels in a direction different from that of the incident laser beam from said optical scanning means.
Claim 4
Dependent Claim
32 words
An image forming apparatus as claimed in claim 1, in which said light absorbing means is provided on a surface of said optical scanning means confronting the surface of said photosensitive body.
Claim 5
Dependent Claim
46 words
An image forming apparatus as claimed in claim 3, in which said light absorbing means comprises a coating on the surface of said optical scanning means, said coating having a high absorbance for substantially absorbing the laser beam reflected by the surface of the photosensitive body.
Claim 6
Dependent Claim
47 words
An image forming apparatus as claimed in claim 3, in which said light absorbing means comprises a member adhered on the surface of said optical scanning means, said member having a high absorbance for substantially absorbing the laser beam reflected by the surface of the photosensitive body.
Claim 7
Dependent Claim
16 words
An image forming apparatus as claimed in claim 5, in which said member comprises a tape.
Claim 8
Dependent Claim
32 words
An image forming apparatus as claimed in claim 3, in which said means comprises a no-gloss black coating for substantially absorbing the laser beam reflected by the surface of said photosensitive body.
Claim 9
Dependent Claim
36 words
An image forming apparatus as claimed in claim 1, in which said light absorbing means comprises a member with a high absorbance for substantially absorbing the laser beam reflected by the surface of said photosensitive body.
Claim 10
Dependent Claim
34 words
An image forming apparatus as claimed in claim 1, in which said light absorbing means comprises a no-gloss black surface for substantially absorbing the laser beam reflected by the surface of said photosensitive body.
Claim 11
Dependent Claim
65 words
An image forming apparatus as claimed in claim 1, which further comprises a charger for uniformly charging the surface of said photosensitive body before scanning by the laser beam, said transfer means having a developing unit for developing the electrostatic image on the surface of said photosensitive body into a visible image, said light absorbing means being provided between said charger and said developing unit.
Claim 12
Dependent Claim
40 words
An image forming apparatus as claimed in claim 10, in which said photosensitive body comprises a rotatable photosensitive drum, said light absorbing means being provided between said charger and said developing unit along a rotating direction of said photosensitive drum.
Claim 13
Dependent Claim
160 words
An image forming apparatus which forms a recorded image of an original image on a recording sheet by an electrophotography method, said image forming apparatus comprising: a photosensitive body; scanning means for scanning a surface of said photosensitive body by a laser beam modulated depending on the original image so as to form an electrostatic image of the original image on the surface of said photosensitive body; transfer means for transferring and fixing the electrostatic image on the surface of said photosensitive body onto the recording sheet; and light absorbing means located at a position confronting the surface of said photosensitive body for substantially absorbing the laser beam which is reflected by a surface portion of said photosensitive body to keep the laser beam reflected by the surface of said photosensitive body from causing a secondary exposure on the surface of said photosensitive body; said surface portion including a photoconductive surface and a conductive substrate surface of said photosensitive body.
Claim 14
Dependent Claim
160 words
An image forming apparatus which forms a recorded image of an original image on a recording sheet by an electrophotography method, said image forming apparatus comprising: a photosensitive body; scanning means for scanning a surface of said photosensitive body by a laser beam modulated depending on the original image so as to form an electrostatic image of the original image on the surface of said photosensitive body; transfer means for transferring and fixing the electrostatic image on the surface of said photosensitive body onto the recording sheet; and light absorbing means located at a position confronting the surface of said photosensitive body for substantially absorbing the laser beam which is reflected by a surface portion of said photosensitive body to keep the laser beam reflected by the surface of said photosensitive body from causing a secondary exposure on the surface of said photosensitive body; said surface portion including a photoconductive surface and a conductive substrate surface of said photosensitive body.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-04-02 | 1993-10-02 | 1994-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-02 | 1997-10-02 | 1998-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-02 | 2001-10-02 | 2002-04-03 | $7700.00 | Window Closed / Lapsed |