US5000548A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microscope objective
Assignee: SA DITE CAOUTHCHOUC MANUFACTURE ET PLASTIQUES 143 BIS RUE YVES LE COZ 7800 VERSAILLES FRANCE
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Filing: 1988-04-25
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Granted: 1991-03-19
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Expires: 2008-04-25
Abstract
Abstract A finite conjugate imaging system useful as a microscope objective comprises four lens elements (10), (11), (12), and (13) disposed coaxially along an optic axis. Lens elements (10) and (12) are made of Hoya LAC7 glass, and lens elements (11) and (13) are made of calcium fluoride crystal. The radii of curvature of the lens elements and the separations between adjacent lens elements are prescribed so as to obtain color correction of the system at five discrete wavelengths.
Inventors
- 👤 Romeo I. Mercado
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:14
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
44 words
A finite conjugate imaging system comprising a plurality of lens elements made of only two different kinds of optical materials, said lens elements coacting with each other to bring paraxial marginal rays passing through said system to a common focus at five discrete wavelengths.
Claim 2
Dependent Claim
44 words
A finite conjugate imaging system comprising a plurality of lens elements made of only two different kinds of optical materials, said lens elements coacting with each other to bring paraxial marginal rays passing through said system to a common focus at five discrete wavelengths.
Claim 3
Dependent Claim
40 words
The finite conjugate imaging system of claim 1 wherein said optical materials comprise calcium fluoride crystal and a glass having a refractive index of approximately 1.65 and an Abbe number of approximately 58.38 at a wavelength of approximately 0.5876 micron.
Claim 4
Dependent Claim
15 words
The finite conjugate imaging system of claim 2 wherein said glass is Hoya LAC7 glass.
Claim 5
Dependent Claim
64 words
The finite conjugate imaging system of claim 3 comprising a first lens element made of Hoya LAC7 glass, a second lens element made of calcium fluoride crystal, a third lens element made of Hoya LAC7 glass, and a fourth lens element made of calcium fluoride crystal, said first, second, third and fourth lens elements being disposed consecutively along an optic axis of the system.
Claim 6
Dependent Claim
84 words
The finite conjugate imaging system of claim 4 wherein said lens elements are configured and positioned with respect to each other approximately as follows: ______________________________________
Radius Thickness Mate-
Surface No.
(mm) (mm) N.sub.d
V.sub.d
rial
______________________________________
0 8.489 [Object Plane]
1 14.783 1.287 1.65160
58.38 LAC7
2 5.761 0.050 Air
3 5.842 3.122 1.43388
95.57 CaF.sub.2
4 -6.772 17.329 Air
5 701.163 1.306 1.65160
58.38 LAC7
6 10.413 0.050 Air
7 9.934 3.225 1.43388
95.57 CaF.sub.2
8 -11.648 170.000 Air
9 [Image Plane]
______________________________________
Claim 7
Dependent Claim
84 words
The finite conjugate imaging system of claim 4 wherein said lens elements are configured and positioned with respect to each other approximately as follows: ______________________________________
Radius Thickness Mate-
Surface No.
(mm) (mm) N.sub.d
V.sub.d
rial
______________________________________
0 12.893 [Object Plane]
1 15.387 1.106 1.65160
58.38 LAC7
2 7.278 0.131 Air
3 7.596 2.902 1.43388
95.57 CaF.sub.2
4 -8.722 6.693 Air
5 407.060 1.091 1.65160
58.38 LAC7
6 9.338 0.100 Air
7 8.876 3.025 1.43388
95.57 CaF.sub.2
8 -14.249 170.000 Air
9 [Image Plane]
______________________________________
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-03-18 | 1994-09-17 | 1995-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-03-18 | 1998-09-17 | 1999-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-03-18 | 2002-09-17 | 2003-03-19 | $7700.00 | Window Closed / Lapsed |