Patent US4770477A successfully refreshed from Google Patents.
US4770477A
Expired / Lapsed
US
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Lens usable in the ultraviolet
Assignee: SVG LITHOGRAPHY Inc A CORP OF
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Filing: 1986-12-04
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Granted: 1988-09-13
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Expires: 2006-12-04
Abstract
Abstract There is disclosed a high performance lens usable in the ultraviolet region of the spectrum. It is a lens of triplet form modified by the addition of double-Gaussshells with a strong field flattening lens near the fast end.
Inventors
- 👤 David R. Shafer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:06
CPC Classifications
G; G02; G02B; G02B3/00; G02B13/00; G02B13/14; G02B13/143
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
85 words
A high performance lens usable in the ultraviolet region of the spectrum which comprises, from the long conjugate side to the short conjugate side: a first positive lens group; a triplet including a first negative meniscus shell, a central negative lens, and a second negative meniscus shell; a second positive lens group; a negative lens group; a negative field flattener; and wherein the power of the central negative lens of the triplet is substantially greater than that of either of said first and second shells.
Claim 2
Dependent Claim
85 words
A high performance lens usable in the ultraviolet region of the spectrum which comprises, from the long conjugate side to the short conjugate side: a first positive lens group; a triplet including a first negative meniscus shell, a central negative lens, and a second negative meniscus shell; a second positive lens group; a negative lens group; a negative field flattener; and wherein the power of the central negative lens of the triplet is substantially greater than that of either of said first and second shells.
Claim 3
Dependent Claim
16 words
The lens of claim 1 wherein all the elements have substantially the same index of refraction.
Claim 4
Dependent Claim
20 words
The lens of claim 1 wherein both of said second positive lens group and said triplet contain negative color-correcting lenses.
Claim 5
Dependent Claim
20 words
The lens of claim 3 wherein the color correcting elements are flint glass and the other elements are fused silica.
References Cited (Backward Citations)
SU871122A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-13 | 1992-03-14 | 1992-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-13 | 1996-03-14 | 1996-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-13 | 2000-03-14 | 2000-09-13 | $7700.00 | Window Closed / Lapsed |