US3773400A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for fixing holographic patterns in electro-optic crystals and the crystals produced thereby
Assignee: RCA Corp
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Filing: 1972-10-10
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Granted: 1973-11-20
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Expires: 1992-10-10
Abstract
Abstract Phase holograms recorded in single crystal electro-optic materials such as undoped or doped lithium niobate and barium sodium niobate doped with iron and molybdenum are fixed so that the holographic pattern is not erased upon readout of the holographic information contained in the crystal. One method for fixing the pattern consists of heating the crystal at an elevated temperature either while or subsequent to writing the holographic pattern in the crystal. An alternate method for fixing the pattern consists of exposing the crystal to ionizing radiation during recording of the holographic information in the crystal.
Inventors
- 👤 J Amodei
- 👤 D Staebler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:17
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/05; G02F1/0541; G11; G11C; G11C13/00; G11C13/04; G11C13/042; G11C13/044; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
46 words
A method according to claim 1 wherein said fixing is accomplished by heating said crystal during or after recordIng of said hologram at an elevated temperature for a time sufficient to accomplish fixing but insufficient to erase said hologram and cooling said crystal to room temperature.
Claim 2
Dependent Claim
21 words
A method according to claim 1 wherein said fixing is accomplished by irradiating said crystal with ionizing radiation prior to recording.
Claim 3
Dependent Claim
17 words
A method according to claim 2 wherein the heating temperature is from about 80*C. to about 180*C.
Claim 4
Dependent Claim
13 words
A method according to claim 3 wherein said ionizing radiation is gamma radiation.
Claim 5
Dependent Claim
32 words
A method according to claim 1 wherein said crystal is selected from the group consisting of lithium niobate, lithium niobate doped with iron and barium sodium niobate doped with iron and molybdenum.
Claim 6
Dependent Claim
10 words
An electro-optic crystal produced by the method of claim 1.
References Cited (Backward Citations)
US3544189A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |