US3623795A
Expired / Lapsed
US
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Electro-optical system
Assignee: RCA Corp
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Filing: 1970-04-24
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Granted: 1971-11-30
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Expires: 1990-04-24
Abstract
Abstract The sharp change in optical properties of ferroelectric and other materials at or near their transition temperature (in the case of ferroelectric material, this may be their ferroelectricparaelectric transition temperature, Curie point) is made use of in light deflectors, light valves and the like. The material is heat biased as, for example, by the application of an alternating voltage of an amplitude sufficient to produce the TANDEL or an analogous effect, to a value close to its transition-temperature. An electrical pulse may then be applied to the material for causing sufficient additional heating to raise the temperature of the material to a different value such as one above the transition temperature. The change in optical properties which results may be employed to deflect or otherwise affect a beam of light applied to the material.
Inventors
- 👤 George William Taylor
- 👤 Arthur Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:10
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/132; G02F1/29; G02F1/31; G02F1/0147; G02F1/03; G02F1/05
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
114 words
An electro-optical system comprising, in combination; a material which exhibits an abrupt change in its optical properties when passing through a given critical temperature; means for heat biasing said material to an operating temperature on one side of, but close to, said critical temperature comprising means for applying an alternating signal to said material of an amplitude such that said operating temperature stabilizes at a value at which the heat lost by the material becomes equal to the heat added to the material; means for directing light at said material; and means responsive to a signal for changing the temperature of said material to a value on the other side of said critical temperature.
Claim 2
Dependent Claim
114 words
An electro-optical system comprising, in combination; a material which exhibits an abrupt change in its optical properties when passing through a given critical temperature; means for heat biasing said material to an operating temperature on one side of, but close to, said critical temperature comprising means for applying an alternating signal to said material of an amplitude such that said operating temperature stabilizes at a value at which the heat lost by the material becomes equal to the heat added to the material; means for directing light at said material; and means responsive to a signal for changing the temperature of said material to a value on the other side of said critical temperature.
Claim 3
Dependent Claim
54 words
A system as set forth in claim 1 wherein said material comprises a ferroelectric material; said critical temperature is the Curie temperature of said material, and said means for applying an alternating signal comprising means for TANDEL stabilizing said temperature, that is, means for switching said material back and forth between its polarization states.
Claim 4
Dependent Claim
27 words
A system as set forth in claim 1 wherein said material comprises a liquid crystal and said temperation comprises the order-disorder transition temperature of said liquid crystal.
Claim 5
Dependent Claim
24 words
A system as set forth in claim 1 wherein said means for directing light comprises means for directing a beam of linearly polarized light.
Claim 6
Dependent Claim
30 words
A system as set forth in claim 4 further including means for receiving the light passing through said material for affecting its intensity as a function of its polarization angle.
Claim 7
Dependent Claim
31 words
A system as set forth in claim 5 further including means for receiving the light passing through said material for deflecting said light through an angle dependent on its polarization angle.
Claim 8
Dependent Claim
28 words
A system as set forth in claim 1 wherein said material comprises a ferroelectric crystal and said temperature is one at which a change in crystal structure occurs.
Claim 9
Dependent Claim
39 words
A system as set forth in claim 1 wherein said material comprises one which exhibits a temperature sensitive, strain stress hysteresis loop and wherein said means for heat biasing comprises means for applying an alternating stress to said material.
Claim 10
Dependent Claim
25 words
A system as set forth in claim 8 wherein said means responsive to a signal comprises a heating coil in operative relationship with said material.
Claim 11
Dependent Claim
113 words
An electro-optical system comprising, in combination; a ferroelectric material having a hysteresis loop and which has substantially different optical properties when above and below its Curie temperature, respectively; means for heat biasing said material to a temperature on one side of, but close to, said Curie temperature comprising means for applying an alternating voltage to said material of an amplitude and frequency to switch the polarization of the material between the two polarization states defined by its hysteresis loop; means for directing a beam of light at said material; and means responsive to a signal for changing the temperature of said material to a value on the other side of said Curie temperature.
Claim 12
Dependent Claim
113 words
An electro-optical system comprising, in combination; a ferroelectric material having a hysteresis loop and which has substantially different optical properties when above and below its Curie temperature, respectively; means for heat biasing said material to a temperature on one side of, but close to, said Curie temperature comprising means for applying an alternating voltage to said material of an amplitude and frequency to switch the polarization of the material between the two polarization states defined by its hysteresis loop; means for directing a beam of light at said material; and means responsive to a signal for changing the temperature of said material to a value on the other side of said Curie temperature.
Claim 13
Dependent Claim
50 words
A system as set forth in claim 10 wherein said material is one which exhibits an abrupt change in its index of refraction at its Curie temperature and wherein said material is of prism shape, said beam of light being directed at one of the nonparallel sides of said prism.
Claim 14
Dependent Claim
114 words
An electro-optical system comprising, in combination; a material which exhibits a change in its optical properties when passing through a given temperature; means for heat biasing said material to a temperature at or close to said given temperature comprising means for applying an alternating signal to said material of an amplitude such that said operating temperature stabilizes at a value at which the heat lost by the material becomes equal to the heat added to the material; means for directing light at said material; and means other than said light, responsive to a signal for changing the temperature of said material to an extent sufficient to cause it to pass through said given temperature.
Claim 15
Dependent Claim
114 words
An electro-optical system comprising, in combination; a material which exhibits a change in its optical properties when passing through a given temperature; means for heat biasing said material to a temperature at or close to said given temperature comprising means for applying an alternating signal to said material of an amplitude such that said operating temperature stabilizes at a value at which the heat lost by the material becomes equal to the heat added to the material; means for directing light at said material; and means other than said light, responsive to a signal for changing the temperature of said material to an extent sufficient to cause it to pass through said given temperature.
Claim 16
Dependent Claim
88 words
A system as set forth in claim 12, wherein said material is transparent and is of a shape such that a beam of light directed substantially perpendicularly to one face strikes the opposite face at a relatively small angle to the normal to that other face, and said means responsive to a signal changes the index of refraction of said material between two states in one of which said material internally reflects the beam of light and in the other of which it refracts the beam of light.
Claim 17
Dependent Claim
15 words
A system as set forth in claim 12 wherein said material is a ferroelectric material.
Claim 18
Dependent Claim
35 words
A system as set forth in claim 12 wherein said material is one which exhibits a temperature-sensitive, strain-stress characteristic and said means for heat biasing comprises means for applying an alternating stress to said material.
References Cited (Backward Citations)
US2780958A
Cited
US3164816A
Cited
US3290619A
Cited
US3391972A
Cited
US3555556A
Cited
GB1120093A
Cited
US3516080A
Cited
US3512864A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-29 | 1975-05-31 | 1975-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-29 | 1979-05-31 | 1979-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-29 | 1983-05-31 | 1983-11-30 | $7700.00 | Window Closed / Lapsed |