US4621890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical apparatus including two afocal systems
Assignee: Canon Inc
•
Filing: 1983-11-28
•
Granted: 1986-11-11
•
Expires: 2003-11-28
Abstract
Abstract An optical apparatus for imaging light from a laser device into a spot shape includes an objective lens for converting parallel rays into a spot-like light, the pupil plane of the objective lens being located at a position conjugate with the emitting plane of the laser device so that the amount of light at the spot will less be changed under variations of emitting angle in the laser device.
Inventors
- 👤 Akiyoshi Suzuki
- 👤 Hideki Ina
- 👤 Kazuo Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:17
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/09; G02B27/0927; G02B27/0938; G02B27/0988
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
204 words
An optical apparatus, comprising: means having an exit end, for emitting a laser beam from said exit end; means for forming a pupil; means for converging, into a spot, the laser beam emitted from said exit end of said emitting means and introduced through said pupil formed by said pupil forming means; and means for forming an image of said exit end of said emitting means substantially on said pupil formed by said pupil forming means, wherein said image forming means includes a first lens component having a forward focus and a rearward focus and a second lens component having a forward focus and a rearward focus, and wherein said forward focus of said first lens component is coincident with said exit end of said emitting means, said rearward focus of said first lens component is coincident with said forward focus of said second lens component, and said rearward focus of said second lens component is coincident with said pupil formed by said pupil forming means, said image forming means further including a third lens component disposed substantially at a point at which said rearward focus of said first lens component and said forward focus of said second lens component coincide with each other.
Claim 2
Dependent Claim
204 words
An optical apparatus, comprising: means having an exit end, for emitting a laser beam from said exit end; means for forming a pupil; means for converging, into a spot, the laser beam emitted from said exit end of said emitting means and introduced through said pupil formed by said pupil forming means; and means for forming an image of said exit end of said emitting means substantially on said pupil formed by said pupil forming means, wherein said image forming means includes a first lens component having a forward focus and a rearward focus and a second lens component having a forward focus and a rearward focus, and wherein said forward focus of said first lens component is coincident with said exit end of said emitting means, said rearward focus of said first lens component is coincident with said forward focus of said second lens component, and said rearward focus of said second lens component is coincident with said pupil formed by said pupil forming means, said image forming means further including a third lens component disposed substantially at a point at which said rearward focus of said first lens component and said forward focus of said second lens component coincide with each other.
Claim 3
Dependent Claim
18 words
An apparatus according to claim 1, wherein said first and second lens components have the same focal length.
Claim 4
Dependent Claim
29 words
An apparatus according to claim 1, wherein each of said first and second lens components has a positive power and wherein said third lens component has a negative power.
Claim 5
Dependent Claim
16 words
An apparatus according to claim 1, wherein said third lens component has a variable focal length.
Claim 6
Dependent Claim
217 words
An optical apparatus, comprising: means having an exit end, for emitting a laser beam from said exit end; means for forming a pupil; means for converging, onto a member, the laser beam emitted from said exit end and introduced through said pupil formed by said pupil forming means; means for forming an image of said exit end of said emitting means substantially on said pupil formed by said pupil forming means, wherein said image forming means includes a first lens component having a forward focus and a rearward focus and a second lens component having a forward focus and a rearward focus, and wherein said forward focus of said first lens component is coincident with said exit end of said emitting means, said rearward focus of said first lens component is coincident with said forward focus of said second lens component, and said rearward focus of said second lens component is coincident with said pupil formed by said pupil forming means, said image forming means further including a third lens component disposed substantially at a point at which said rearward focus of said first lens component and said forward focus of said second lens component coincide with each other; and means for sensing the laser beam diffracted by the member to detect the position of the member.
Claim 7
Dependent Claim
217 words
An optical apparatus, comprising: means having an exit end, for emitting a laser beam from said exit end; means for forming a pupil; means for converging, onto a member, the laser beam emitted from said exit end and introduced through said pupil formed by said pupil forming means; means for forming an image of said exit end of said emitting means substantially on said pupil formed by said pupil forming means, wherein said image forming means includes a first lens component having a forward focus and a rearward focus and a second lens component having a forward focus and a rearward focus, and wherein said forward focus of said first lens component is coincident with said exit end of said emitting means, said rearward focus of said first lens component is coincident with said forward focus of said second lens component, and said rearward focus of said second lens component is coincident with said pupil formed by said pupil forming means, said image forming means further including a third lens component disposed substantially at a point at which said rearward focus of said first lens component and said forward focus of said second lens component coincide with each other; and means for sensing the laser beam diffracted by the member to detect the position of the member.
Claim 8
Dependent Claim
146 words
An optical apparatus, comprising: means having an exit end, for emitting a laser beam from said exit end; means for forming a pupil; means for converging, into a spot, the laser beam emitted from said exit end of said emitting means and introduced through said pupil formed by said pupil forming means; and means for forming an image of said exit end of said emitting means substantially on said pupil formed by said pupil forming means, said image forming means including a first afocal system, which is subjected to a vibration, the vibration being the same as a vibration of said emitting means and a second afocal system, which is subjected to a vibration, the vibration being the same as a vibration of said converging means, said first and second afocal systems being disposed in the order named from the exit end of said emitting means.
Claim 9
Dependent Claim
146 words
An optical apparatus, comprising: means having an exit end, for emitting a laser beam from said exit end; means for forming a pupil; means for converging, into a spot, the laser beam emitted from said exit end of said emitting means and introduced through said pupil formed by said pupil forming means; and means for forming an image of said exit end of said emitting means substantially on said pupil formed by said pupil forming means, said image forming means including a first afocal system, which is subjected to a vibration, the vibration being the same as a vibration of said emitting means and a second afocal system, which is subjected to a vibration, the vibration being the same as a vibration of said converging means, said first and second afocal systems being disposed in the order named from the exit end of said emitting means.
Claim 10
Dependent Claim
29 words
An apparatus according to claim 6, wherein said first afocal system has a magnification smaller than 1 and wherein said second afocal system has a magnification larger than 1.
Claim 11
Dependent Claim
25 words
An apparatus according to claim 7, wherein the magnification of said first afocal system is a reciprocal of the magnification of said second afocal system.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-10 | 1990-05-12 | 1990-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-10 | 1994-05-12 | 1994-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-10 | 1998-05-12 | 1998-11-11 | $7700.00 | Window Closed / Lapsed |