Patent US3520541A successfully refreshed from Google Patents.
US5287218A
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Re-imaging optical system including refractive and diffractive optical elements
Assignee: Raytheon Co
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Filing: 1992-04-07
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Granted: 1994-02-15
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Expires: 2012-04-07
Abstract
Abstract A re-imaging optical system (10) has a ref lective objective (12) providing an intermediate image of the object being viewed and a relay (14) including refractive (32, 62) and diffractive (34, 72) optical elements. The system is capable of re-imaging the intermediate image onto an image plane (16) with the characteristic advantages of reflective and refractive systems while eliminating their deficiencies.
Inventors
- 👤 Chungte W. Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:38
CPC Classifications
G; G02; G02B; G02B17/00; G02B17/08; G02B17/0852; G02B17/0804; G02B17/0812; G02B17/082; G02B17/0832; G02B27/00; G02B27/0025; G02B27/0037; G02B27/42; G02B27/4205; G02B27/4211; G02B27/4216
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
96 words
A re-imaging optical system comprising: an objective including a primary and secondary mirror, said primary and secondary mirrors having conic or higher order aspheric surfaces, said primary mirror receiving and projecting a radiation beam of a viewed object, said secondary mirror positioned to receive and reflect said radiation beam from said primary mirror, said primary mirror forming an intermediate image of said viewed object; a relay means including a refractive optical element and a diffractive optical element positioned to receive said radiation beam from said secondary mirror to re-image said intermediate image onto an image plane.
Claim 2
Dependent Claim
96 words
A re-imaging optical system comprising: an objective including a primary and secondary mirror, said primary and secondary mirrors having conic or higher order aspheric surfaces, said primary mirror receiving and projecting a radiation beam of a viewed object, said secondary mirror positioned to receive and reflect said radiation beam from said primary mirror, said primary mirror forming an intermediate image of said viewed object; a relay means including a refractive optical element and a diffractive optical element positioned to receive said radiation beam from said secondary mirror to re-image said intermediate image onto an image plane.
Claim 3
Dependent Claim
27 words
The system according to claim 1 wherein a fold mirror is positioned between said primary and secondary mirrors for relaying said radiation beam to said secondary mirror.
Claim 4
Dependent Claim
19 words
The system according to claim 1 wherein said primary mirror and said secondary mirror are each positive power mirrors.
Claim 5
Dependent Claim
17 words
The ssytem according to claim 1 wherein said refractive and diffractive optical elements have positive optical power.
Claim 6
Dependent Claim
19 words
The system according to claim 1 wherein said refractive and diffractive optical elements are a single hybrid optical element.
Claim 7
Dependent Claim
16 words
The system according to claim 1 wherein said refractive optical element includes a pluraliyt of lenses.
Claim 8
Dependent Claim
27 words
The system according to claim 6 wherein said plurality of lenses includes positive and negative power lenses, the overall power of said plurality of lenses being positive.
Claim 9
Dependent Claim
21 words
The system according to claim 7 wherein an exit pupil is positioned between said secondary mirror and said plurality of lenses.
Claim 10
Dependent Claim
29 words
The system according to claim 6 wherein the combination of a group of crown-flint lenses and a refractive-diffractive hybrid optical element corrects primary and the secondary axial chromatic aberrations.
Claim 11
Dependent Claim
28 words
The system according to claim 6 wherein the combination of a group of crown-flint lenses and a refractive-diffractive hybrid optical element corrects primary and secondary lateral chromatic aberrations.
Claim 12
Dependent Claim
21 words
The system according to claim 1 wherein an exit pupil is positioned between said imaging plane and said diffractive optical element.
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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) | 1997-02-14 | 1997-08-16 | 1998-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-14 | 2001-08-16 | 2002-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-14 | 2005-08-16 | 2006-02-15 | $7700.00 | Window Closed / Lapsed |