Patent US5093745A successfully refreshed from Google Patents.
US5093745A
Expired / Lapsed
US
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Light beam scanning optical system
Assignee: Minolta Co Ltd
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Filing: 1990-08-01
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Granted: 1992-03-03
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Expires: 2010-08-01
Abstract
Abstract In a light beam scanning optical system, a toroidal lens and a spherical mirror or a cylindrical mirror function in cooperation to rectify the scanning speed of a light beam deflected at an equiangular velocity by a rotative deflection device to be uniform over the range from the center to both edges of scanning area in the main scanning direction. The toroidal lens is further arranged to maintain each reflective facet of the rotative deflection device and the light collecting surface in the conjugate relation, thereby rectifying an error of image inclination of each reflective facet and at the same time regulating the direction of emission of the light beam so as to lessen the curvature of the field.
Inventors
- 👤 Muneo Kuroda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:46
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/04; H04N1/113; H04N1/1135; G; G02; G02B; G02B27/00; G02B27/0025; G02B27/0031
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
135 words
A light beam scanning optical system comprising: emitting means for emitting a light beam; converging means for converging the light beam emitted from said emitting means into a straight line in a direction parallel to a beam scanning direction; a deflection device disposed in the vicinity where the light beam is converged into said straight line, said deflection device being rotatable about a rotational axis thereof for deflecting the light beam at an equiangular velocity; a spherical mirror which receives and reflects the light beam having been deflected from said deflection device; and a toroidal lens disposed between the deflection device and the spherical mirror in optical alignment therewith, wherein the light beam impinges onto said deflection device at an angle other than 90 degrees with respect to the rotational axis of the deflection device.
Claim 2
Dependent Claim
135 words
A light beam scanning optical system comprising: emitting means for emitting a light beam; converging means for converging the light beam emitted from said emitting means into a straight line in a direction parallel to a beam scanning direction; a deflection device disposed in the vicinity where the light beam is converged into said straight line, said deflection device being rotatable about a rotational axis thereof for deflecting the light beam at an equiangular velocity; a spherical mirror which receives and reflects the light beam having been deflected from said deflection device; and a toroidal lens disposed between the deflection device and the spherical mirror in optical alignment therewith, wherein the light beam impinges onto said deflection device at an angle other than 90 degrees with respect to the rotational axis of the deflection device.
Claim 3
Dependent Claim
19 words
A light beam scanning optical system as claimed in claim 1, wherein said deflection device comprises a polygonal mirror.
Claim 4
Dependent Claim
35 words
A light beam scanning optical system as claimed in claim 1, further comprising a plane mirror which receives and reflects the light beam having been reflected from said spherical mirror to a beam receiving plane.
Claim 5
Dependent Claim
25 words
A light beam scanning optical system as claimed in claim 3, wherein said plane mirror is positioned between the toroidal lens and the spherical mirror.
Claim 6
Dependent Claim
25 words
A light beam scanning optical system as claimed in claim 3, wherein said plane mirror is positioned between the deflection device and the toroidal lens.
Claim 7
Dependent Claim
135 words
A light beam scanning optical system comprising: emitting means for emitting a light beam; converging means for converging the light beam emitted from said emitting means into a straight line in a direction parallel to a beam scanning direction; a deflection device disposed in the vicinity where the light beam is converged into said straight line, said deflection device being rotatable about a rotational axis thereof for deflecting the light beam at an equiangular velocity; a cylindrical mirror which receives and reflects the light beam having been deflected from said deflection device; and a toroidal lens disposed between the deflection device and the cylindrical mirror in optical alignment therewith, wherein the light beam impinges onto said deflection device at an angle other than 90 degrees with respect to the rotational axis of the deflection device.
Claim 8
Dependent Claim
135 words
A light beam scanning optical system comprising: emitting means for emitting a light beam; converging means for converging the light beam emitted from said emitting means into a straight line in a direction parallel to a beam scanning direction; a deflection device disposed in the vicinity where the light beam is converged into said straight line, said deflection device being rotatable about a rotational axis thereof for deflecting the light beam at an equiangular velocity; a cylindrical mirror which receives and reflects the light beam having been deflected from said deflection device; and a toroidal lens disposed between the deflection device and the cylindrical mirror in optical alignment therewith, wherein the light beam impinges onto said deflection device at an angle other than 90 degrees with respect to the rotational axis of the deflection device.
Claim 9
Dependent Claim
19 words
A light beam scanning optical system as claimed in claim 6, wherein said deflection device comprises a polygonal mirror.
Claim 10
Dependent Claim
35 words
A light beam scanning optical system as claimed in claim 6, further comprising a plane mirror which receives and reflects the light beam having been reflected from said cylindrical mirror to a beam receiving plane.
Claim 11
Dependent Claim
25 words
A light beam scanning optical system as claimed in claim 8, wherein said plane mirror is positioned between the toroidal lens and the cylindrical mirror.
Claim 12
Dependent Claim
25 words
A light beam scanning optical system as claimed in claim 8, wherein said plane mirror is positioned between the deflection device and the toroidal lens.
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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) | 1995-03-03 | 1995-09-02 | 1996-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-03 | 1999-09-02 | 2000-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-03 | 2003-09-02 | 2004-03-03 | $7700.00 | Window Closed / Lapsed |