Patent US4775205A successfully refreshed from Google Patents.
US4775205A
Expired / Lapsed
US
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Light-beam scanning apparatus having two beam waists
Assignee: Konica Minolta Inc
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Filing: 1987-03-13
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Granted: 1988-10-04
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Expires: 2007-03-13
Abstract
Abstract A light beam scanning apparatus including a light source for emitting a light beam and a rotatable polygon mirror having at least one surface for reflecting the light beam to a second surface being scanned. A flat field lens is provided between the polygon mirror and the second surface and an optical system is provided close to the second surface. The optical system has a light converging effect only in the vertical direction perpendicular to the scanning direction, and the light beam forms a first beam waist between the flat field lens and the optical system, and a second beam waist substantially on the second surface.
Inventors
- 👤 Toshio Muramatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:27
CPC Classifications
G; G02; G02B; G02B26/00; G02B26/08; G02B26/10; G02B26/12
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
105 words
A light beam scanning apparatus comprising a light source for emitting a light beam, a rotatable polygon mirror having at least one first surface for reflecting said light beam to a second surface being scanned, a flat field lens provided between said polygon mirror and said second surface, an optical system provided close to said second surface, said optical system having a light converging effect only in the vertical direction perpendicular to the scanning direction, said light beam being constituted to form a first beam waist between said flat field lens and the optical system, and a second beam waist substantially on said second surface.
Claim 2
Dependent Claim
105 words
A light beam scanning apparatus comprising a light source for emitting a light beam, a rotatable polygon mirror having at least one first surface for reflecting said light beam to a second surface being scanned, a flat field lens provided between said polygon mirror and said second surface, an optical system provided close to said second surface, said optical system having a light converging effect only in the vertical direction perpendicular to the scanning direction, said light beam being constituted to form a first beam waist between said flat field lens and the optical system, and a second beam waist substantially on said second surface.
Claim 3
Dependent Claim
38 words
The light beam scanning apparatus of claim 1 wherein said flat field lens and said optical system being designed to place said first surface and said second surface in substantially conjugated relation with regard to said vertical direction.
Claim 4
Dependent Claim
37 words
The apparatus of claim 1 further comprising a light beam shaping means provided between said light source and said polygon mirror, whereby the light beam becomes wide and flat in the direction parallel to the scanning direction.
Claim 5
Dependent Claim
13 words
The apparatus of claim 3 wherein said light beam is a laser beam.
Claim 6
Dependent Claim
32 words
The apparatus of claim 3 wherein said optical system is a cylindrical lens or a concave reflecting mirror whose convergent effect on said light beam is uniformly extended over the scanning direction.
Claim 7
Dependent Claim
32 words
The apparatus of claim 4 wherein said optical system is a cylindrical lens or a concave reflecting mirror whose convergent effect on said light beam is uniformly extended over the scanning direction.
Claim 8
Dependent Claim
13 words
The apparatus of claim 1 wherein said light beam is a laser beam.
Claim 9
Dependent Claim
32 words
The apparatus of claim 1 wherein said optical system is a cylindrical lens or a concave reflecting mirror whose convergent effect on said light beam is uniformly extended over the scanning direction.
Claim 10
Dependent Claim
35 words
The apparatus of claim 3 wherein said light beam shaping means comprises, from the light source side, light expanding means comprising two spherical lenses, a long focus cylindrical lens, and a short forces cylindrical lens.
Claim 11
Dependent Claim
29 words
The apparatus of claim 3 wherein said light beam shaping means comprises, from the light source side, a single cylindrical lens, and light expanding means comprising two spherical lenses.
Claim 12
Dependent Claim
32 words
The apparatus of claim 7 wherein said optical system is a cylindrical lens or a concave reflecting mirror whose convergent effect on said light beam is uniformly extended over the scanning direction.
Claim 13
Dependent Claim
35 words
The apparatus of claim 4 wherein said light beam shaping means comprises, from the light source side, light expanding means comprising two spherical lenses, a long focus cylindrical lens, and a short focus cylindrical lens.
Claim 14
Dependent Claim
35 words
The apparatus of claim 3 wherein said light beam shaping means comprises, from the light source side, light expanding means comprising two spherical lenses, a long focus cylindrical lens, and a short focus cylindrical lens.
Claim 15
Dependent Claim
35 words
The apparatus of claim 6 wherein said light beam shaping means comprises, from the light source side, light expanding means comprising two spherical lenses, a long focus cylindrical lens, and a short focus cylindrical lens.
Claim 16
Dependent Claim
29 words
The apparatus of claim 4 wherein said light beam shaping means comprises, from the light source side, a single cylindrical lens, and light expanding means comprising two spherical lenses.
Claim 17
Dependent Claim
29 words
The apparatus of claim 3 wherein said light beam shaping means comprises, from the light source side, a single cylindrical lens, and light expanding means comprising two spherical lenses.
Claim 18
Dependent Claim
29 words
The apparatus of claim 6 wherein said light beam shaping means comprises, from the light source side, a single cylindrical lens, and light expanding means comprising two spherical lenses.
Claim 19
Dependent Claim
113 words
A light beam scanning method comprising providing a light beam source, a rotatable polygon mirror having at least one first surface, a flat field lens between said polygon mirror and a second surface, and an optical system close to said second surface, emitting a light beam toward said first surface, changing a light beam radius and a wavefront radius so that a first beam waist is formed between said flat field lens and said optical system, and a second beam waist is formed substantially on said second surface, scanning said second surface by rotating said polygon mirror, whereby a substantially uniform spot size of said light beam is obtained along a scanning line.
Claim 20
Dependent Claim
113 words
A light beam scanning method comprising providing a light beam source, a rotatable polygon mirror having at least one first surface, a flat field lens between said polygon mirror and a second surface, and an optical system close to said second surface, emitting a light beam toward said first surface, changing a light beam radius and a wavefront radius so that a first beam waist is formed between said flat field lens and said optical system, and a second beam waist is formed substantially on said second surface, scanning said second surface by rotating said polygon mirror, whereby a substantially uniform spot size of said light beam is obtained along a scanning line.
References Cited (Backward Citations)
JPS50334A
Cited
US4294506A
Cited
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