US3340765A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Projection system
Assignee: AT&T Inc
•
Filing: 1964-07-27
•
Granted: 1967-09-12
•
Expires: 1984-07-27
Abstract
No abstract record available.
Inventors
- 👤 Donald R Herriott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:37
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/132; G03B21/06; Y; Y10; Y10S; Y10S353/00; Y10S353/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
114 words
OPTICAL APPARATUS FOR FORMING AN OPTICAL IMAGE OF A TRANSPARENT SURFACE COMPRISING, IN COMBINATION; A TRANSPARENT MEMBER FOR PROVIDING AN EASILY ACCESSIBLE WRITING SURFACE, MEANS FOR ILLUMINATING SAID TRANSPARENT MEMBER, FRESNEL LENS MEANS IN CONTACT WITH SAID TRANSPARENT MEMBER AND OPPOSITELY DISPOSED FROM THE ILLUMINATED SIDE OF SAID TRANSPARENT MEMBER FOR COLLIMATING THE INCIDENT LIGHT RAYS TRANSMITTED BY SAID TRANSPARENT MEMBER, REFLECTION MEANS IN CONTACT WITH SAID LENS MEANS FOR REFLECTING SAID COLLIMATED LIGHT RAYS, SAID LENS MEANS FOCUSING SAID REFLECTED COLLIMATED LIGHT RAYS IN A DIRECTION DIFFERENT FROM THAT OF SAID INCIDENT LIGHT RAYS, AND PROJECTION MEANS DISPLACED FROM SAID ILLUMINATING MEANS FOR INTERCEPTING REFLECTED COLLIMATED LIGHT RAYS FOCUSED BY SAID LENS MEANS.
Claim 2
Dependent Claim
114 words
OPTICAL APPARATUS FOR FORMING AN OPTICAL IMAGE OF A TRANSPARENT SURFACE COMPRISING, IN COMBINATION; A TRANSPARENT MEMBER FOR PROVIDING AN EASILY ACCESSIBLE WRITING SURFACE, MEANS FOR ILLUMINATING SAID TRANSPARENT MEMBER, FRESNEL LENS MEANS IN CONTACT WITH SAID TRANSPARENT MEMBER AND OPPOSITELY DISPOSED FROM THE ILLUMINATED SIDE OF SAID TRANSPARENT MEMBER FOR COLLIMATING THE INCIDENT LIGHT RAYS TRANSMITTED BY SAID TRANSPARENT MEMBER, REFLECTION MEANS IN CONTACT WITH SAID LENS MEANS FOR REFLECTING SAID COLLIMATED LIGHT RAYS, SAID LENS MEANS FOCUSING SAID REFLECTED COLLIMATED LIGHT RAYS IN A DIRECTION DIFFERENT FROM THAT OF SAID INCIDENT LIGHT RAYS, AND PROJECTION MEANS DISPLACED FROM SAID ILLUMINATING MEANS FOR INTERCEPTING REFLECTED COLLIMATED LIGHT RAYS FOCUSED BY SAID LENS MEANS.
References Cited (Backward Citations)
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Cited
US2647437A
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Cited
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Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-09-11 | 1971-03-13 | 1971-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-09-11 | 1975-03-13 | 1975-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-09-11 | 1979-03-13 | 1979-09-12 | $7700.00 | Window Closed / Lapsed |