US3707325A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical imaging system
Assignee: Individual
•
Filing: 1970-07-23
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Granted: 1972-12-26
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Expires: 1990-07-23
Abstract
Abstract An optical imaging system is described which includes a mirror system comprising a convex spherical mirror and an apertured concave spherical mirror having coincident principal axes. It is shown that by placing a plane mirror and a second convex spherical mirror in the path taken by the rays which emerge from the mirror system the focal distance can be increased, resulting in an acceptable light-shadow ratio with a non-excessively large aperture and also in a very good correction for spherical aberration.
Inventors
- 👤 George Eduard Gerard Hardeman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:51
CPC Classifications
G; G02; G02B; G02B17/00; G02B17/02; G02B17/06; G02B17/0647; G02B17/0652
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
89 words
An optical imaging system which comprising a convex spherical mirror, an apertured concave spherical mirror the optical axes of which mirrors coincide, said mirrors having a common center of curvature, whereby a beam of radiation passing through an aperture in the concave mirror and impinging on the convex mirror will be reflected on to the surface of the concave mirror, a plane mirror in the path of the radiation from the concave mirror, and a second convex spherical mirror in the path of the radiation from the plane mirror.
Claim 2
Dependent Claim
89 words
An optical imaging system which comprising a convex spherical mirror, an apertured concave spherical mirror the optical axes of which mirrors coincide, said mirrors having a common center of curvature, whereby a beam of radiation passing through an aperture in the concave mirror and impinging on the convex mirror will be reflected on to the surface of the concave mirror, a plane mirror in the path of the radiation from the concave mirror, and a second convex spherical mirror in the path of the radiation from the plane mirror.
Claim 3
Dependent Claim
31 words
An optical imaging system as claimed in claim 1, wherein the ratio between the radii of curvature of the spherical mirrors is such that the system is corrected for spherical aberration.
Claim 4
Dependent Claim
35 words
An optical imaging system as claimed in claim 1 wherein the plane mirror is located between the first convex mirror and the common center of curvature at a slight distance in front of this center.
Claim 5
Dependent Claim
33 words
An optical imaging system as claimed in claim 1, wherein the spacing between the edges of the first and second convex mirrors is equal to 0.02 times the radius of the concave mirror.
References Cited (Backward Citations)
US2380887A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-12-26 | 1976-06-26 | 1976-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-26 | 1980-06-26 | 1980-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-26 | 1984-06-26 | 1984-12-26 | $7700.00 | Window Closed / Lapsed |