Patent US5291340A successfully refreshed from Google Patents.
US5291340A
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Reflecting objective system
Assignee: Olympus Corp
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Filing: 1992-08-31
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Granted: 1994-03-01
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Expires: 2012-08-31
Abstract
Abstract A reflecting objective system comprising three or more spherical reflecting mirrors arranged symmetrically with regard to an optical axis common thereto and has spherical aberration corrected very favorably. By using a single or plural aspherical surfaces, this reflecting objective system can be modified so as to comprise two or more reflecting mirrors and correct not only the spherical aberration but also the offaxial aberrations.
Inventors
- 👤 Shingo Kashima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:24
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/02; G02B21/04; G02B17/00; G02B17/02; G02B17/06; G02B17/0605; G02B17/061; G02B17/0626; G02B17/0631; G02B17/0647; G02B17/0652
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
218 words
A reflecting objective system that excludes a refracting optical element and receives light from an object separate from the system with a given distance therebetween and acts to form an image of the object, comprising, in the travelling order of light incident from the object side: a first reflecting mirror having a positive optical power, a second reflecting mirror and a third reflecting mirror at least one of which has a positive optical power, and a fourth reflecting mirror having a positive optical power, each reflecting mirror having different reflecting surfaces than the other reflecting mirrors, a light beam from said object being reflected from the mirrors in the order of first, second, third and fourth reflecting mirrors without the beam intersecting an optical axis of the system, wherein total optical power of said first, second and third reflecting mirrors has a positive value, and at least one of the reflecting surfaces of said first reflecting mirror and said fourth reflecting mirror being as aspherical surface, an absolute value of powers of said second and third reflecting mirrors being smaller than an absolute value of powers of said first and fourth reflecting mirrors, said third reflecting mirror being disposed between said first reflecting mirror and said second reflecting mirror, and said reflecting objective system satisfying the condition (12):
Claim 2
Dependent Claim
218 words
A reflecting objective system that excludes a refracting optical element and receives light from an object separate from the system with a given distance therebetween and acts to form an image of the object, comprising, in the travelling order of light incident from the object side: a first reflecting mirror having a positive optical power, a second reflecting mirror and a third reflecting mirror at least one of which has a positive optical power, and a fourth reflecting mirror having a positive optical power, each reflecting mirror having different reflecting surfaces than the other reflecting mirrors, a light beam from said object being reflected from the mirrors in the order of first, second, third and fourth reflecting mirrors without the beam intersecting an optical axis of the system, wherein total optical power of said first, second and third reflecting mirrors has a positive value, and at least one of the reflecting surfaces of said first reflecting mirror and said fourth reflecting mirror being as aspherical surface, an absolute value of powers of said second and third reflecting mirrors being smaller than an absolute value of powers of said first and fourth reflecting mirrors, said third reflecting mirror being disposed between said first reflecting mirror and said second reflecting mirror, and said reflecting objective system satisfying the condition (12):
Claim 3
Dependent Claim
54 words
01≦|ΔM 13 |·(f/L 01 2 )≦0.1 (12) wherein the reference symbol ΔM 13 represents a mechanical distance between said first reflecting mirror and said third reflecting mirror, f is the focal length of the reflecting objective system, and the reference symbol L 01 represents a distance between said object and said first reflecting mirror.
Claim 4
Dependent Claim
54 words
01≦|ΔM 13 |·(f/L 01 2 )≦0.1 (12) wherein the reference symbol ΔM 13 represents a mechanical distance between said first reflecting mirror and said third reflecting mirror, f is the focal length of the reflecting objective system, and the reference symbol L 01 represents a distance between said object and said first reflecting mirror.
Claim 5
Dependent Claim
40 words
A reflecting objective system according to claim 1, wherein said reflecting objective system satisfies the following condition (11): |φ.sub.4 |≦0.1 (11) wherein φ 4 =f·(2/r 4 ), where r 4 designates the radius of curvature of the fourth reflecting mirror.
Claim 6
Dependent Claim
41 words
A reflecting objective system according to claim 1, wherein said first reflecting mirror includes an opening on the optical axis, and said fourth reflecting mirror is disposed at a position where said optical axis is shielded by said fourth reflecting mirror.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-02-28 | 1997-08-30 | 1998-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-28 | 2001-08-30 | 2002-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-28 | 2005-08-30 | 2006-03-01 | $7700.00 | Window Closed / Lapsed |