Patent DE884516C successfully refreshed from Google Patents.
US3639030A
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Holographic method of farming contour lines in an image utilizing light of limited coherence length
Assignee: Nikon Corp
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Filing: 1970-06-02
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Granted: 1972-02-01
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Expires: 1990-06-02
Abstract
Abstract This invention provides a device for forming hologram. FabryPerot etalon is interposed in the parallel reference light rays. The distance D of Fabry-Perot etalon is made substantially equal to the coherent length L of the light to be used, so as to produce a number of reference light ray groups having a light path difference of 2D for increasing the depth of reproduction. Further, by making the distance D satisfying 2D>L, contour lines in terms of 2D are formed for measuring the depth of an object.
Inventors
- 👤 Tadao Tsuruta
- 👤 Yoshinobu Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:41
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/04; G03H1/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
84 words
In the formation of a hologram by the exposure of a hologram plate to coherent radiation of coherent length L including exposure to a reference beam and exposure to a beam reflected from an object having a depth dimension much greater than said coherence length, the method of providing contour lines representative of the depth of the object comprising: interposing a Fabry-Perot etalon in the optical path of said reference beam, the distance D between the mirrors of said etalon being such that 2D>L.
Claim 2
Dependent Claim
84 words
In the formation of a hologram by the exposure of a hologram plate to coherent radiation of coherent length L including exposure to a reference beam and exposure to a beam reflected from an object having a depth dimension much greater than said coherence length, the method of providing contour lines representative of the depth of the object comprising: interposing a Fabry-Perot etalon in the optical path of said reference beam, the distance D between the mirrors of said etalon being such that 2D>L.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |