US5225924A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical beam scanning system
Assignee: Dainippon Screen Manufacturing Co Ltd
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Filing: 1990-03-29
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Granted: 1993-07-06
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Expires: 2010-03-29
Abstract
Abstract An optical beam scanning system for scanning photosensitive material (1) comprises a laser (201), a beam splitter (204) for producing multibeams (LB a , LB b ), AOM's (207a, 207b), a multibeam adjuster (300) for turning the multibeams to intersect each other at a prescribed point (P C ), a horizontal expander (211), an AOD (213), a vertical expander (214), a deflection direction adjuster (400) for rotating a deflection direction of the multibeams, and a variable focusing mechanism (500) comprising a plurality of object lenses (501-504). A pixel pitch and a spot diameter on the photosensitive material can be changed separately from each other by exchanging the object lenses and by adjusting an angle of intersection of multibeams (B a , B b ) by means of the multibeam adjuster. Cylindrical lenses of the horizontal and vertical expanders are so positioned that they compensate a cylindrical lensing effect of the AOD.
Inventors
- 👤 Hideaki Ogawa
- 👤 Eiichi Tamaki
- 👤 Takumi Yoshida
- 👤 Yasuyuki Wada
- 👤 Akira Kuwabara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:30
CPC Classifications
G; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K15/1238; G06K15/1257; G02; G02B; G02B26/00; G02B26/08; G02B26/10; G02B26/108; G06K15/1204; G06K15/1209
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
138 words
An optical beam scanning system for scanning a photosensitive material with optical beams while moving said optical beams relatively to said photosensitive material, comprising: means for generating a plurality of optical beams; means for modulating said plurality of optical beams; beam turning means for turning modulated optical beams to thereby produce a first beam group consisting of optical beams which intersect each other at an angle of intersection at a prescribed point; angle changing means connected to said beam turning means for rotationally displacing said beam turning means to thereby change said angle of intersection of said first beam group; deflecting means placed at said prescribed point for periodically deflecting said first beam group to thereby produce a second beam group; and focusing means for focusing each optical beam of said second beam group on said photosensitive material.
Claim 2
Dependent Claim
138 words
An optical beam scanning system for scanning a photosensitive material with optical beams while moving said optical beams relatively to said photosensitive material, comprising: means for generating a plurality of optical beams; means for modulating said plurality of optical beams; beam turning means for turning modulated optical beams to thereby produce a first beam group consisting of optical beams which intersect each other at an angle of intersection at a prescribed point; angle changing means connected to said beam turning means for rotationally displacing said beam turning means to thereby change said angle of intersection of said first beam group; deflecting means placed at said prescribed point for periodically deflecting said first beam group to thereby produce a second beam group; and focusing means for focusing each optical beam of said second beam group on said photosensitive material.
Claim 3
Dependent Claim
24 words
An optical beam scanning system in accordance with claim 1, wherein said focusing means comprises a focusing optical system whose focal length is changeable.
Claim 4
Dependent Claim
51 words
An optical beam scanning system in accordance with claim 2, wherein said focusing optical system comprises a plurality of objective lenses whose focal lengths are different from each other, and a mechanism for selecting one of said plurality of objective lenses to focus said second beam group on said photosensitive material.
Claim 5
Dependent Claim
19 words
An optical beam scanning system in accordance with claim 2, wherein said focusing optical system comprises a zoom lens.
Claim 6
Dependent Claim
64 words
An optical beam scanning system in accordance with claim 2 further comprising direction rotation means placed between said deflecting means and said focusing means for rotating a deflection direction of said second beam group, and means connected to said direction rotating means for rotating said direction rotating means to thereby change an angle of rotation of said deflection direction of said second beam group.
Claim 7
Dependent Claim
19 words
An optical beam scanning system in accordance with claim 5, wherein said direction rotating means has a pechan prism.
Claim 8
Dependent Claim
19 words
An optical beam scanning system in accordance with claim 5, wherein said direction rotating means has a dove prism.
Claim 9
Dependent Claim
192 words
An optical beam scanning system in accordance with claim 5, wherein said deflecting means is an acousto-optic deflector having a cylindrical lensing effect by which said acousto-optic deflector is equivalent to a concave lens, and said optical beam scanning system further comprises: a first one-directional expander to expand each beam of said first beam group in a first direction, said first one-directional expander consisting of first and second cylindrical lenses placed between said angle changing means and said acousto-optic deflector, said first cylindrical lens making each beam of said first beam group a divergent ray, said second cylindrical lens making said divergent ray a convergent ray converging at an image-side focal point of said acousto-optic deflector, and a second one-directional expander to expand each beam of said second beam group in a second direction perpendicular to said first direction while maintaining each beam leaving said second one-directional expander a parallel bundle of rays, said second one-directional expander consisting of first and second cylindrical lenses placed between said acousto-optic deflector and said direction rotating means, said first and second cylindrical lenses of said second one-directional expander having refracting powers in said second direction.
Claim 10
Dependent Claim
192 words
An optical beam scanning system in accordance with claim 5, wherein said deflecting means is an acousto-optic deflector having a cylindrical lensing effect by which said acousto-optic deflector is equivalent to a convex lens, and said optical beam scanning system further comprises: a first one-directional expander to expand each beam of said first beam group in a first direction, said first one-directional expander consisting of first and second cylindrical lenses placed between said angle changing means and said acousto-optic deflector, said first cylindrical lens making each beam of said first beam group a divergent ray, said second cylindrical lens making said divergent ray a convergent ray converging at an object-side focal point of said acousto-optic deflector, and a second one-directional expander to expand each beam of said second beam group in a second direction perpendicular to said first direction while maintaining each beam leaving said second one-directional expander a parallel bundle of rays, said second one-directional expander consisting of first and second cylindrical lenses placed between said acousto-optic deflector and said direction rotating means, said first and second cylindrical lenses of said second one-directional expander having refracting powers in said second direction.
Claim 11
Dependent Claim
64 words
An optical beam scanning system in accordance with claim 1 further comprising: direction rotating means placed between said deflecting means and said focusing means for rotating a deflection direction of said second beam group, and means connected to said direction rotating means for rotating said direction rotating means to thereby change an angle of rotation of said deflection direction of said second beam group.
Claim 12
Dependent Claim
19 words
An optical beam scanning system in accordance with claim 10, wherein said direction rotating means has a pechan prism.
Claim 13
Dependent Claim
19 words
An optical beam scanning system in accordance with claim 10, wherein said direction rotating means has a dove prism.
Claim 14
Dependent Claim
192 words
An optical beam scanning system in accordance with claim 10, wherein said deflecting means is an acousto-optic deflector having a cylindrical lensing effect by which said acousto-optic deflector is equivalent to a concave lens, and said optical beam scanning system further comprises: a first one-directional expander to expand each beam of said first beam group in a first direction, said first one-directional expander consisting of first and second cylindrical lenses placed between said angle changing means and said acousto-optic deflector, said first cylindrical lens making each beam of said first beam group a divergent ray, said second cylindrical lens making said divergent ray a convergent ray converging at an image-side focal point of said acousto-optic deflector, and a second one-directional expander to expand each beam of said second beam group in a second direction perpendicular to said first direction while maintaining each beam leaving said second one-directional expander a parallel bundle of rays, said second one-directional expander consisting of first and second cylindrical lenses placed between said acousto-optic deflector and said direction rotating means, said first and second cylindrical lenses of said second one-directional expander having refracting powers in said second direction.
Claim 15
Dependent Claim
193 words
An optical beam scanning system in accordance with claim 10, wherein said deflecting means is an acousto-optic deflector having a cylindrical lensing effect by which said acousto-optic deflector is equivalent to a convex lens, and said optical beam scanning system further comprises: a first one-directional expander to expand each beam of said first beam group in a first direction, said first one-directional expander consisting of first and second cylindrical lenses placed between said angle changing means and said acousto-optic deflector, said first cylindrical lens making each beam of said first beam group a divergent ray, said second cylindrical lens making said divergent ray a convergent ray converging at an object-side focal point of said acousto-optic deflector, and a second one-directional expander to expand each beam of said second beam group in a second direction perpendicular to said first direction while maintaining each beam leaving said second one-directional expander a parallel bundle of rays, said second one-directional expander consisting of first and second cylindrical lenses placed between said acousto-optic deflector and said direction rotating means, and said first and second cylindrical lenses of said second one-directional expander having refracting power in said second direction.
Claim 16
Dependent Claim
191 words
An optical beam scanning system in accordance with claim 1, wherein said deflecting means is an acousto-optic deflector having a cylindrical lensing effect by which said acousto-optic deflector is equivalent to a concave lens, and said optical beam scanning system further comprises: a first one-directional expander to expand each beam of said first beam group in a first direction, said first one-directional expander consisting of first and second cylindrical lenses placed between said angle changing means and said acousto-optic deflector, said first cylindrical lens making each beam of said first beam group a divergent ray, said second cylindrical lens making said divergent ray a convergent ray converging at an image-side focal point of said acousto-optic deflector, and a second one-directional expander to expand each beam of said second beam group in a second direction perpendicular to said first direction while maintaining each beam leaving said second one-directional expander a parallel bundle of rays, said second one-directional expander consisting of first and second cylindrical lenses placed between said acousto-optic deflector and said focusing means, said first and second cylindrical lenses of said second one-directional expander having refracting powers in said second direction.
Claim 17
Dependent Claim
191 words
An optical beam scanning system in accordance with claim 1, wherein said deflecting means is an acousto-optic deflector having a cylindrical lensing effect by which said acousto-optic deflector is equivalent to a convex lens, and said optical beam scanning system further comprises: a first one-directional expander to expand each beam of said first beam group in a first direction, said first one-directional expander consisting of first and second cylindrical lenses placed between said angle changing means and said acousto-optic deflector, said first cylindrical lens making each beam of said first beam group a divergent ray, said second cylindrical lens making said divergent ray a convergent ray converging at an object-side focal point of said acousto-optic deflector, and a second one-directional expander to expand each beam of said second beam group in a second direction perpendicular to said first direction while maintaining each beam leaving said second one-directional expander a parallel bundle of rays, said second one-directional expander consisting of first and second cylindrical lenses placed between said acousto-optic deflector and said focusing means, said first and second cylindrical lenses of said second one-directional expander having refracting powers in said second direction.
Claim 18
Dependent Claim
147 words
An optical beam scanning system comprising: means for generating an optical beam; a first one-directional beam expander having a plurality of cylindrical lenses to expand said optical beam in a prescribed direction, said first one-directional beam expander having a posterior focal point; an acousto-optic deflector receiving an expanded optical beam from said first one-directional beam expander for deflecting said expanded optical beam in said prescribed direction, wherein said acousto-optic deflector has a cylindrical lensing effect by which said acousto-optic deflector is equivalent to a lens having an anterior focal point; and a second one-directional beam expander, placed at the image side of said acousto-optic deflector, having a plurality of cylindrical lenses to expand said deflected beam in a second direction perpendicular to said prescribed direction, wherein said posterior focal point of said first one-directional beam expander is coincident with said anterior focal point of said acousto-optic deflector.
Claim 19
Dependent Claim
147 words
An optical beam scanning system comprising: means for generating an optical beam; a first one-directional beam expander having a plurality of cylindrical lenses to expand said optical beam in a prescribed direction, said first one-directional beam expander having a posterior focal point; an acousto-optic deflector receiving an expanded optical beam from said first one-directional beam expander for deflecting said expanded optical beam in said prescribed direction, wherein said acousto-optic deflector has a cylindrical lensing effect by which said acousto-optic deflector is equivalent to a lens having an anterior focal point; and a second one-directional beam expander, placed at the image side of said acousto-optic deflector, having a plurality of cylindrical lenses to expand said deflected beam in a second direction perpendicular to said prescribed direction, wherein said posterior focal point of said first one-directional beam expander is coincident with said anterior focal point of said acousto-optic deflector.
Claim 20
Dependent Claim
58 words
An optical beam scanning system in accordance with claim 17, wherein said acousto-optic deflector is equivalent to a concave lens, and said first one-directional beam expander comprising: a first cylindrical lens for making said optical beam a divergent ray; and a second cylindrical lens for converging said divergent ray at said anterior focal point of said acousto-optic deflector.
Claim 21
Dependent Claim
60 words
An optical beam scanning system in accordance with claim 17, wherein said acousto-optic deflector is equivalent to a convex lens, and said first one-directional beam expander comprising: a first cylindrical lens for making said optical beam a first divergent ray; and a second cylindrical lens for diverging said first divergent ray from said anterior focal point of said acousto-optic deflector.
References Cited (Backward Citations)
US3365579A
Cited
US3435228A
Cited
US4000493A
Cited
US3746427A
Cited
US3835249A
Cited
US4107701A
Cited
US4209224A
Cited
US4257016A
Cited
US4455485A
Cited
US4426134A
Cited
US4773754A
Cited
JPS60107828A
Cited
EP0157383A1
Cited
US4841135A
Cited
JPS62204141A
Cited
JPS62226118A
Cited
US4810068A
Cited
EP0240347A2
Cited
JPS63193124A
Cited
DE3806785A1
Cited
US4863226A
Cited
US4733252A
Cited
US4855761A
Cited
US4971413A
Cited
US4896169A
Cited
EP0299455A2
Cited
US5002348A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-07-05 | 1997-01-04 | 1997-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-05 | 2001-01-04 | 2001-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-05 | 2005-01-04 | 2005-07-06 | $7700.00 | Window Closed / Lapsed |