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US4037943A Expired / Lapsed US ⏱️ 0.0 years remaining

Reflection type image forming optical system having a large angle of view

Assignee: Nikon Corp
•
Filing: 1975-03-10
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Granted: 1977-07-26
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Expires: 1995-03-10
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Abstract

Abstract A reflection type image forming optical system having a large angle of view comprises a convex mirror for reflecting incident light and a concave mirror. The concave mirror is disposed with the reflecting surface thereof facing the reflecting surface of the convex mirror so that light reflected by the convex mirror at a large angle with respect to the normal thereof enters the concave mirror at a large angle and that light reflected by the convex mirror at a small angle with respect to the normal thereof enters the concave mirror at a small angle. The concave mirror is arranged so that the distance between the center of curvature of the convex mirror and that of the concave mirror is greater than half the radius of curvature of the concave mirror.

Inventors

  • 👤 Satoru Anzai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 23:09
CPC Classifications
G; G02; G02B; G02B17/00; G02B17/02; G02B17/06; G02B17/0605; G02B17/0615

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 154 words
A reflection type image forming optical system having a large angle of view comprising: a convex spherical reflecting mirror for reflecting incident light; a concave spherical reflecting mirror disposed with the reflecting surface thereof facing the reflecting surface of the convex mirror, the concave mirror being arranged so that the distance between the center of curvature of the convex mirror and the center of curvature of the concave mirror is greater than half the radius of curvature of the concave mirror; and a stop disposed between said reflecting surfaces of the convex and concave mirrors, the stop being arranged to select only light that enters the concave mirror at a large angle with respect to the normal thereof, when reflected by the convex mirror at a large angle, and that enters the concave mirror at a small angle with respect to the normal thereof, when reflected by the convex mirror at a small angle.
Claim 2
Dependent Claim 154 words
A reflection type image forming optical system having a large angle of view comprising: a convex spherical reflecting mirror for reflecting incident light; a concave spherical reflecting mirror disposed with the reflecting surface thereof facing the reflecting surface of the convex mirror, the concave mirror being arranged so that the distance between the center of curvature of the convex mirror and the center of curvature of the concave mirror is greater than half the radius of curvature of the concave mirror; and a stop disposed between said reflecting surfaces of the convex and concave mirrors, the stop being arranged to select only light that enters the concave mirror at a large angle with respect to the normal thereof, when reflected by the convex mirror at a large angle, and that enters the concave mirror at a small angle with respect to the normal thereof, when reflected by the convex mirror at a small angle.
Claim 3
Dependent Claim 59 words
A system according to claim 1, wherein with a focal length (f) of the system of 100 at F/3.3 to furnish an angle of view of 60°, the distance between the center of curvature of convex mirror and the center of curvature of the concave mirror is 173.4, and the radius of curvature of the concave mirror is 263.3.
Claim 4
Dependent Claim 59 words
A system according to claim 1, wherein with a focal length (f) of the system of 100 at F/3.3 to furnish an angle of view of 60°, the distance between the center of curvature of convex mirror and the center of curvature of the concave mirror is 300.0, and the radius of curvature of the concave mirror is 300.0.

References Cited (Backward Citations)

US2737850A Cited
US3112355A Cited
US3203328A Cited
US3707325A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-07-25 1981-01-24 1981-07-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-07-25 1985-01-24 1985-07-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-07-25 1989-01-24 1989-07-26 $7700.00 Window Closed / Lapsed

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