US4964704A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical system for use of a laser processing machine
Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1989-08-17
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Granted: 1990-10-23
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Expires: 2009-08-17
Abstract
Abstract An improved optical system suitable for laser processing in semiconductor manufacture. The system is composed of three convex lenses. By suitably selecting the type of each of the lenses, a limited spherical aberration is obtained without compromising the numerical aperture.
Inventors
- 👤 Hisato Shinohara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:03
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/08
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
98 words
An optical system for use with a laser processing machine comprising at least: first, second and third optical lens means arranged in this order from the light incidence side, each lens means having the same function as a lens comprising a front convex surface in the light incidence side and an opposite surface whose radius of curvature is larger than that of said convex surface, wherein the radius of curvature in the incidence side of the lens corresponding to said third optical lens means is less than that of the lens corresponding to said second optical lens means.
Claim 2
Dependent Claim
98 words
An optical system for use with a laser processing machine comprising at least: first, second and third optical lens means arranged in this order from the light incidence side, each lens means having the same function as a lens comprising a front convex surface in the light incidence side and an opposite surface whose radius of curvature is larger than that of said convex surface, wherein the radius of curvature in the incidence side of the lens corresponding to said third optical lens means is less than that of the lens corresponding to said second optical lens means.
Claim 3
Dependent Claim
25 words
The optical system of claim 1 wherein said first, second and third optical lens means respectively each have the same function as a cylindrical lens.
Claim 4
Dependent Claim
15 words
The optical system of claim 1 wherein the numerical aperture system is larger than 0.0015.
Claim 5
Dependent Claim
45 words
The optical system of claim 3 further comprising a fourth optical lens means disposed at the light incidence side of the first optical lens means having the same function as a concave lens disposed at the light incidence side of the first optical lens means.
Claim 6
Dependent Claim
16 words
An optical system as in claim 1 where the laser processing machine includes an excimer laser.
Claim 7
Dependent Claim
19 words
An optical system as in claim 1 where each of said first, second, and third lens means comprises quartz.
References Cited (Backward Citations)
US4043641A
Cited
JPS6021016A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-10-22 | 1994-04-23 | 1994-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-22 | 1998-04-23 | 1998-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-22 | 2002-04-23 | 2002-10-23 | $7700.00 | Window Closed / Lapsed |