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US4042293A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid crystal devices having diode characteristics

Assignee: RCA Corp
•
Filing: 1975-07-14
•
Granted: 1977-08-16
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Expires: 1995-07-14
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Abstract

Abstract The device comprises an enclosure including two spaced apart electrodes for applying an electric field through a film of liquid crystal material between the electrodes. Disposed on one of the electrodes, between it and the liquid crystal film, is a semiconductor material layer. The semiconductor layer has a rectifying or non-ohmic contact with the liquid crystal film, and has an ohmic or low resistance contact with the electrode. The layer has a resistance, when the rectifying contact is reverse biased, greater than that of the liquid crystal film, and, when the rectifying contact is forward biased, less than that of the film.

Inventors

  • 👤 Joseph John Hanak
  • 👤 Ronald Norman Friel
  • 👤 Lawrence Alan Goodman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 00:07
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/136; G02F1/1362; G02F1/136277; Y; Y10; Y10S; Y10S359/00; Y10S359/90

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 122 words
The method of operating a liquid crystal device of the type comprising a pair of spaced apart electrodes, a liquid crystal between said electrodes, and a semiconductor material disposed between and in contact with one of said electrodes and said liquid crystal material, the contact between said semiconductor material and said one of said electrodes being ohmic and the contact between said semiconductor material and said liquid crystal material being non-ohmic, The resistance associated with said semiconductor material being greater or less than that of said liquid crystal material depending upon the polarity of voltage applied between said electrodes, said method comprising selectively activating and deactivating said liquid crystal material by selectively applying one or the opposite polarity voltages between said electrodes.
Claim 2
Independent Claim 122 words
The method of operating a liquid crystal device of the type comprising a pair of spaced apart electrodes, a liquid crystal between said electrodes, and a semiconductor material disposed between and in contact with one of said electrodes and said liquid crystal material, the contact between said semiconductor material and said one of said electrodes being ohmic and the contact between said semiconductor material and said liquid crystal material being non-ohmic, The resistance associated with said semiconductor material being greater or less than that of said liquid crystal material depending upon the polarity of voltage applied between said electrodes, said method comprising selectively activating and deactivating said liquid crystal material by selectively applying one or the opposite polarity voltages between said electrodes.
Claim 3
Dependent Claim 45 words
The method of operating a liquid crystal device as in claim 1 including using a liquid crystal device wherein the resistance associated with said semiconductor material varies with the polarity of voltage applied between said electrodes by a factor of about 10 2 or greater.
Claim 4
Dependent Claim 13 words
The method as in claim 2 wherein said semiconductor material comprises zinc oxide.

References Cited (Backward Citations)

US3499112A Cited
US3663086A Cited
US3730607A Cited
US3809456A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-08-15 1981-02-14 1981-08-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-08-15 1985-02-14 1985-08-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-08-15 1989-02-14 1989-08-16 $7700.00 Window Closed / Lapsed

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