US3871745A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Visual information storage and display device
Assignee: NTT Inc
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Filing: 1973-03-21
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Granted: 1975-03-18
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Expires: 1993-03-21
Abstract
Abstract A visual information storage and display device provided with a thin ceramic sheet prepared from a transparent ferroelectric ceramic block having an optical uniaxial anisotropy, wherein the direction of polarization axis orients antiparallel and that of optical axis orients parallel to the direction of applied pressure at hot-pressing stage.
Inventors
- 👤 Shigeru Waku
- 👤 Shintaro Hayashi
- 👤 Hiroyuki Shibata
- 👤 Takehisa Kawashima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:25
CPC Classifications
G; G11; G11C; G11C11/00; G11C11/21; G11C11/22; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/055; G11C13/00; G11C13/04; G11C13/047
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
133 words
An information storage and display device which comprises a thin ceramic sheet having an optical axis oriented before the application of electrodes thereto at an angle of between 30* and 90* with the normal direction to the surface of the sheet, said sheet being cut out from a transparent ferroelectric ceramic block having an optically uniaxial anisotropy without annealing, wherein the direction of polarization axis orients antiparallel and that of optical axis orients parallel to direction of applied pressure during and after the hot-pressing stage; photoconductive films and transparent electrodes for writing and erasing informations by light and provided over both sides of said ceramic sheet; a light source and a power source for writing and erasing information by light; and a means of polarized light optic system for displaying the storaged informations.
Claim 2
Dependent Claim
133 words
An information storage and display device which comprises a thin ceramic sheet having an optical axis oriented before the application of electrodes thereto at an angle of between 30* and 90* with the normal direction to the surface of the sheet, said sheet being cut out from a transparent ferroelectric ceramic block having an optically uniaxial anisotropy without annealing, wherein the direction of polarization axis orients antiparallel and that of optical axis orients parallel to direction of applied pressure during and after the hot-pressing stage; photoconductive films and transparent electrodes for writing and erasing informations by light and provided over both sides of said ceramic sheet; a light source and a power source for writing and erasing information by light; and a means of polarized light optic system for displaying the storaged informations.
Claim 3
Dependent Claim
90 words
The device as claimed in claim 1, wherein said transparent ferroelectric ceramic block is a solid-solution consisting essentially of Pb(Zr0.65Ti0.35)O3 and adding at least one element of lanthanum (La), samarium (Sm), neodymium (Nd), tantalum (Ta) and wolfram (W) in a molar fraction of not more than 8%, which is prepared by hot-pressing and has an optically uniaxial anisotropy wherein the direction of polarization axis orients antiparallel and that of optical axis orients parallel to the direction of applied pressure at hot-pressing stage at a temperature of less than Curie point.
Claim 4
Dependent Claim
29 words
The device as claimed in claim 1, wherein said angle between the normal direction to the surface of the sheet and the optical axis is between 70* and 60*.
Claim 5
Dependent Claim
27 words
The device as claimed in claim 1, wherein said light soUrce for writing and erasing informations by light includes a means for illumination spatially modulated by informations.
Claim 6
Dependent Claim
36 words
The device as claimed in claim 1 which further comprises a means for illumination by scanning light beam, the intensity of which being modulated by the application of electric field and the informations to be recorded.
Claim 7
Dependent Claim
29 words
The device as claimed in claim 1, wherein said means of polarized light optic system is composed of a monochromatic light source, a polarizer, a compensator and an analyzer.
Claim 8
Dependent Claim
128 words
An information storage and display device which comprises a thin ceramic sheet having an optical axis oriented before the application of electrodes thereto at an angle of between 30* and 90* with the normal direction to the surface of the sheet, said sheet being cut out from a transparent ferroelectric ceramic block having an optically uniaxial anisotropy formed without annealing wherein the direction of polarization axis orients antiparallel and that of optical axis orients parallel to the direction of applied pressure in the hot-pressing; transparent electrodes in a matrix array for electrically writing and erasing informations and provided on both sides of said thin ceramic sheet; an electric circuit for electrically writing and erasing informations; and a means of polarized light optic system for displaying the storaged informations.
Claim 9
Dependent Claim
128 words
An information storage and display device which comprises a thin ceramic sheet having an optical axis oriented before the application of electrodes thereto at an angle of between 30* and 90* with the normal direction to the surface of the sheet, said sheet being cut out from a transparent ferroelectric ceramic block having an optically uniaxial anisotropy formed without annealing wherein the direction of polarization axis orients antiparallel and that of optical axis orients parallel to the direction of applied pressure in the hot-pressing; transparent electrodes in a matrix array for electrically writing and erasing informations and provided on both sides of said thin ceramic sheet; an electric circuit for electrically writing and erasing informations; and a means of polarized light optic system for displaying the storaged informations.
Claim 10
Dependent Claim
82 words
The device as claimed in claim 7, wherein said transparent ferroelectric ceramic block is a solid-solution consisting essentially of Pb(Zr0.65Ti0.35)O3 and adding at least one element of lanthanum (La), samarium (Sm), neodymium (Nd), tantalum (Ta) and wolfram (W) in a molar fraction of not more than 8%, which is prepared by hot-pressing and has an optically uniaxial anisotropy wherein the direction of polarization axis orients antiparallel and that of optical axis orients parallel to the direction of applied pressure at hot-pressing stage.
Claim 11
Dependent Claim
30 words
The device as claimed in claim 7, wherein said angle between the normal direction to the surface of the sheet and the optical axis is selected from 70* to 60*.
Claim 12
Dependent Claim
23 words
The device as claimed in claim 7, wherein said electronic circuit is composed of X address selecting circuit and Y address selecting circuit.
Claim 13
Dependent Claim
29 words
The device as claimed in claim 7, wherein said means of polarized light optic system is composed of a monochromatic light source, a polarizer, a compensator and an analyzer.
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) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |