US3572941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photochromic device based upon photon absorption
Assignee: RCA Corp
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Filing: 1967-12-07
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Granted: 1971-03-30
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Expires: 1987-12-07
Abstract
Abstract A device capable of displaying and storing three dimensional images comprises a photochromic target and a light source. The light source emits light of a power density and a frequency so as to be substantially transmitted by the photochromic target. The power density and frequency of the emitted light is such that when light is focused at a spot to provide an increased power density at this spot, double photon absorption of the light by the photochromic target occurs and causes a change in the optical density characteristics of the photochromic target in the region of absorption. The device therefor includes means for focusing the light.
Inventors
- 👤 Zoltan Kiss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 02:26
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/002; H04N7/005; G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/0338; G02F1/05; G02F1/0541; G02F1/35; G02F1/3526; G11; G11C; G11C13/00; G11C13/04; G11C13/041
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
87 words
An image storage and display device comprising: a. a three-dimensional photochromic target of a given photon absorption optical density change characteristic; b. a source of light, double photon bombardment of said target by which, produces a change in optical density in said target, said light having a power density at said target such that when unfocused, relatively no double photon absorption occurs; and c. means for focusing said light in said target to increase the double photon absorption and thus produce a measurable optical density change therein.
Claim 2
Dependent Claim
87 words
An image storage and display device comprising: a. a three-dimensional photochromic target of a given photon absorption optical density change characteristic; b. a source of light, double photon bombardment of said target by which, produces a change in optical density in said target, said light having a power density at said target such that when unfocused, relatively no double photon absorption occurs; and c. means for focusing said light in said target to increase the double photon absorption and thus produce a measurable optical density change therein.
Claim 3
Dependent Claim
19 words
The device described in claim 1 including means for modulating the focal point of said light in said target.
Claim 4
Dependent Claim
39 words
The device described in claim 2 wherein said modulating means is at least partially electrooptical in nature and is capable of varying the focal point in three dimensions so as to create a three dimensional image on said target.
Claim 5
Dependent Claim
10 words
The device described in claim 2 including amplitude modulating means.
Claim 6
Dependent Claim
13 words
The device claimed in claim 1 wherein said light source is a laser.
Claim 7
Dependent Claim
34 words
The device described in claim 1 wherein said photochromic target is comprised of calcium fluoride doped with rare earth ions in a reduced state or strontium titanate doped with ions of molybdenum and iron.
Claim 8
Dependent Claim
27 words
The device described in claim 6 wherein the photochromic target is a single crystal of either CaF2 doped with La or SrTi03 doped with Fe and Mo.
Claim 9
Dependent Claim
24 words
The device described in claim 7 wherein the light source is a laser of the type chosen from ruby, argon, krypton, and zenon lasers.
Claim 10
Dependent Claim
48 words
The device described in claim 8 including means for electrooptically modulating the amplitude and means for electrooptically modulating the position of the light impinging on said target each of said modulating means being coupled to a signal source so as to create a predetermined image on said target.
Claim 11
Dependent Claim
133 words
An image storage and display device comprising: a. a three-dimensional photochromic target adapted to have an image formed therein, said target characterized in that its optical density characteristics alter when energy in a certain absorption band is caused to be absorbed by said target due to double photon absorption; b. a source for emitting high intensity light of a power density and frequency such that when focused on said target a portion of said light is absorbed by said target due to double photon absorption in the region of the focal point causing said target to change its optical density characteristics in said region, and when unfocused said light is substantially transmitted by said target; and c. means for focusing said light on selected regions of said target for forming an image therein.
Claim 12
Dependent Claim
133 words
An image storage and display device comprising: a. a three-dimensional photochromic target adapted to have an image formed therein, said target characterized in that its optical density characteristics alter when energy in a certain absorption band is caused to be absorbed by said target due to double photon absorption; b. a source for emitting high intensity light of a power density and frequency such that when focused on said target a portion of said light is absorbed by said target due to double photon absorption in the region of the focal point causing said target to change its optical density characteristics in said region, and when unfocused said light is substantially transmitted by said target; and c. means for focusing said light on selected regions of said target for forming an image therein.
References Cited (Backward Citations)
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 |