Patent US5218481A successfully refreshed from Google Patents.
US5218481A
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US
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Optical inspection apparatus
Assignee: LAROY OPTICAL Ltd A BRITISH Co
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Filing: 1991-05-10
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Granted: 1993-06-08
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Expires: 2011-05-10
Abstract
Abstract An optical projection system for projecting a magnified image of an object includes a 1:2 relay lens having a magnification of ×0.5. The object is illuminated by a collimated substantially parallel light beam from a source and the 1:2 relay lens produces an intermediate shadow image at its focal plane. A projection lens is located to project a magnified final image of the intermediate image on the screen. While it is preferred that the relay lens has a magnification of ×0.5, the relay lens may have a different magnification less than ×1.
Inventors
- 👤 John McBeath
- 👤 Graham Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:48
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/8803
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
60 words
Optical inspection apparatus for producing a projected image of an object comprising a first lens structure having a magnification less than ×1 to produce an intermediate image of said object, said intermediate image being of reduced dimensions relative to the dimensions of the object and a second lens structure to produce a projected magnified final image of the intermediate image.
Claim 2
Dependent Claim
60 words
Optical inspection apparatus for producing a projected image of an object comprising a first lens structure having a magnification less than ×1 to produce an intermediate image of said object, said intermediate image being of reduced dimensions relative to the dimensions of the object and a second lens structure to produce a projected magnified final image of the intermediate image.
Claim 3
Dependent Claim
18 words
Optical inspection apparatus as claimed in claim 1 wherein said first lens structure has a magnification of ×0.5.
Claim 4
Dependent Claim
37 words
Optical inspection apparatus as claimed in claim 1 wherein the second lens structure has an optical diameter corresponding to less than the dimensions of the object being viewed and corresponding to the dimensions of the intermediate image.
Claim 5
Dependent Claim
75 words
Optical inspection apparatus for producing a projected image of an object comprising a source of light for illumination of said object with a collimated beam of light of substantially parallel rays; first lens means having a magnification less than ×1 to produce an intermediate shadow image of said object, said shadow image having dimensions less than corresponding dimensions of said object; and second lens means to produce a projected magnified image of said shadow image.
Claim 6
Dependent Claim
75 words
Optical inspection apparatus for producing a projected image of an object comprising a source of light for illumination of said object with a collimated beam of light of substantially parallel rays; first lens means having a magnification less than ×1 to produce an intermediate shadow image of said object, said shadow image having dimensions less than corresponding dimensions of said object; and second lens means to produce a projected magnified image of said shadow image.
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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) | 1996-06-07 | 1996-12-07 | 1997-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-07 | 2000-12-07 | 2001-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-07 | 2004-12-07 | 2005-06-08 | $7700.00 | Window Closed / Lapsed |