US3701122A
Expired / Lapsed
US
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Ferroelectric domain shifting devices
Assignee: AT&T Inc
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Filing: 1971-08-25
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Granted: 1972-10-24
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Expires: 1991-08-25
Abstract
Abstract Ferroelectric crystals which are also ferroelastic, such as gadolinium molybdate, can support stable internal ferroelectric polarization domains. These domains are expanded and moved in the ferroelectric crystal by means of a sequence of voltages applied to electrodes on the surface of the crystal. Thereby, optically readable, shift register logic functions are achieved using (for readout) an incident optical beam with respect to which the ferroelectric domains are birefringent.
Inventors
- 👤 Joseph Edward Geusic
- 👤 Terence John Nelson
- 👤 David Paul Schinke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 01:03
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/005; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/05; G02F3/00; G09; G09G; G09G3/00; G11C13/00; G11C13/04; G11C13/047
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
20 words
An optical display device including: a. the device recited in claim 1; and b. optical means to detect the domain.
Claim 2
Dependent Claim
21 words
A device according to claim 2 in which the electrodes are both transparent to the optical radiation in the optical means.
Claim 3
Dependent Claim
27 words
The device recited in claim 2 in which the optical means include an optical polarizer located in the path of an optical beam exiting from the plate.
Claim 4
Independent Claim
143 words
A device which comprises: a. a ferroelectric plate capable of supporting a polarized domain, the boundary of which can be displaced in the plate in response to electric fields; b. an array of electrodes on a surface portion of the plate including a second electrode as next neighbor to a first electrode and a third electrode as next neighbor to the second electrode; and c. means for applying voltage pulses to the array of electrodes in a sequence consisting of a first pulse of one polarity to the first electrode, a second pulse of opposite polarity to the third electrode, a third pulse of the one polarity to the second electrode, a fourth pulse of opposite polarity to the first electrode, a fifth pulse of the one polarity to the third electrode, and a sixth pulse of opposite polarity to the second electrode.
Claim 5
Dependent Claim
20 words
The device recited in claim 5 in which the first, second, and third electrodes are transparent to an optical beam.
Claim 6
Dependent Claim
34 words
Apparatus which comprises: a. the device recited in claim 6; and b. a source of the optical beam, arranged to direct the beam so that it propagates through the first, second, and third electrodes.
Claim 7
Independent Claim
135 words
A device which comprises: a. first, second, and third ferroelectric plates each of which is capable of supporting polarized domains, the boundaries of each of which can be displaced in response to electric fields, the plates arranged such that a beam of optical radiation can propagate through all the plates; b. at least two transparent electrodes located on major surfaces of each of the plates; and c. voltage means connected to the electrodes sufficient to move the boundaries of the domains in response to the voltage applied to the electrodes such that each domain is extended from coextension with one electrode to coextension with two electrodes, so that the relative phase retardation of perpendicular polarization components of the beam of radiation propagating through the three plates is changed by a predetermined phase by the voltage.
Claim 8
Dependent Claim
26 words
The device recited in claim 8 in which the plates have a thickness such that the predetermined phase is pi /2 or odd integral multiple thereof.
Claim 9
Dependent Claim
19 words
The device recited in claim 9 which further includes a quarter-wave plate located in the path of the beam.
References Cited (Backward Citations)
US3229261A
Cited
US3362019A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |