Patent US3143980A successfully refreshed from Google Patents.
US4433893A
Expired / Lapsed
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Process for producing holograms
Assignee: Fujifilm Holdings Corp
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Filing: 1982-01-12
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Granted: 1984-02-28
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Expires: 2002-01-12
Abstract
Abstract A hologram having excellent durability and high diffraction efficiency and process for producing same is disclosed, wherein a glass hologram is subjected to a surface treatment with hydrofluoric acid.
Inventors
- 👤 Masazi Yokota
- 👤 Masaru Noguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:50
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/04; G03H1/18; G03F; G03F7/00; G03F7/0005; G03F7/001; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
29 words
In a process for producing glass holograms having an uneven surface, the improvement wherein a surface of said glass holograms is subjected to a surface treatment with hydrofluoric acid.
Claim 2
Dependent Claim
29 words
In a process for producing glass holograms having an uneven surface, the improvement wherein a surface of said glass holograms is subjected to a surface treatment with hydrofluoric acid.
Claim 3
Dependent Claim
30 words
A process of claim 1, wherein said hydrofluoric acid is 50% hydrofluoric acid diluted 20 times to 100 times and is applied to said surface for 30 to 130 seconds.
References Cited (Backward Citations)
US3944420A
Cited
US4056395A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-27 | 1987-08-29 | 1988-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-27 | 1991-08-29 | 1992-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-27 | 1995-08-29 | 1996-02-28 | $7700.00 | Window Closed / Lapsed |