US3572879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Producing high quality holograms by copying
Assignee: Agfa Gevaert AG
•
Filing: 1968-07-30
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Granted: 1971-03-30
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Expires: 1988-07-30
Abstract
Abstract The production of a hologram free from undesirable line structures by forming a phase hologram by bleaching an absorption hologram and then copying the phase hologram using a gas discharge tube to radiate the phase hologram with and thus produce a hologram completely free from coarse residual fringes.
Inventors
- 👤 Heinrich Nassenstein
- 👤 Manfred Kliemann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:04
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/04; G03H1/20; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
64 words
In the method of producing holograms free from coarse residual fringes the steps of first bleaching an absorption hologram to form a phase hologram, projecting a light beam of short coherence length from a light source through said phase hologram and subsequently impinging said beam on a photographic plate so as to create a holographic copy of the phase hologram on the photographic plate.
Claim 2
Dependent Claim
64 words
In the method of producing holograms free from coarse residual fringes the steps of first bleaching an absorption hologram to form a phase hologram, projecting a light beam of short coherence length from a light source through said phase hologram and subsequently impinging said beam on a photographic plate so as to create a holographic copy of the phase hologram on the photographic plate.
Claim 3
Dependent Claim
21 words
In the method as claimed in claim 1 using a gas discharge tube to produce the short coherence length light beam.
Claim 4
Dependent Claim
16 words
In the method as claimed in claim 1 using an incandescent lamp as said light source.
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) | 1974-03-29 | 1974-09-28 | 1975-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-29 | 1978-09-28 | 1979-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-29 | 1982-09-28 | 1983-03-30 | $7700.00 | Window Closed / Lapsed |