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US4744636A Expired / Lapsed US ⏱️ 0.0 years remaining

Electron beam-addressed liquid crystal cell having coating layer for secondary electron emission

Assignee: Tektronix Inc
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Filing: 1987-05-05
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Granted: 1988-05-17
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Expires: 2007-05-05
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Abstract

Abstract An electron beam-addressed liquid crystal cell for a light valve. The cell (40) includes liquid crystal material (42) sandwiched between two substrates (16, 44). One substrate (44) is addressed by the electron beam (60a, 60b) and includes a coating (51) having a rate of secondary electron emission greater than the characteristic rate of secondary electron emissions of the base layer (49) of the substrate (44). The enhanced secondary electron emission characteristics of the coated substrate (44) permit the cell to be modulated with relatively lower electron beam current for correspondingly higher image resolution.

Inventors

  • 👤 Duane A. Haven
  • 👤 Thomas S. Buzak
  • 👤 Rolf S. Vatne

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 21:55
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/133348

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 148 words
An electron beam-addressed liquid crystal cell for a light valve, comprising: (a) a first transparent substrate; (b) a second transparent substrate positioned adjacent to the first substrate and having a base layer with an outer surface, the base layer being formed of material that emits secondary electrons at a first rate of emission when struck by an electron beam propagating with a predetermined energy; (c) a coating applied to the outer surface of the base layer of the second substrate, the coating being formed of material that emits secondary electrons at a second rate of emission when struck by the electron beam propagating with the predetermined energy, the second rate of emission being greater than the first rate of emission; and (d) liquid crystal means sandwiched between the first and second substrates for modulating incident light electrooptically as the liquid crystal cell is struck by the electron beam.
Claim 2
Dependent Claim 148 words
An electron beam-addressed liquid crystal cell for a light valve, comprising: (a) a first transparent substrate; (b) a second transparent substrate positioned adjacent to the first substrate and having a base layer with an outer surface, the base layer being formed of material that emits secondary electrons at a first rate of emission when struck by an electron beam propagating with a predetermined energy; (c) a coating applied to the outer surface of the base layer of the second substrate, the coating being formed of material that emits secondary electrons at a second rate of emission when struck by the electron beam propagating with the predetermined energy, the second rate of emission being greater than the first rate of emission; and (d) liquid crystal means sandwiched between the first and second substrates for modulating incident light electrooptically as the liquid crystal cell is struck by the electron beam.
Claim 3
Dependent Claim 11 words
The cell of claim 1 wherein the coating is magnesium oxide.
Claim 4
Dependent Claim 17 words
The cell of claim 2 wherein the coating is covered with a thin film of magnesium fluoride.
Claim 5
Dependent Claim 33 words
The cell of claim 1 further including conductor means positioned within the light valve to extend across the path of the electron beam for selectively attracting secondary electrons emitted from the second substrate.
Claim 6
Dependent Claim 84 words
A target substrate for a liquid crystal cell that is addressed by an eletron beam having a predetermined energy, comprising: (a) a base layer formed of material that emits secondary electrons at a first rate of emission when addressed by the beam; and (b) a coating applied to the base, the coating being formed of material that emits secondary electrons at a second rate of emission when addressed by the beam, the second rate of emission being greater than the first rate of emission.
Claim 7
Dependent Claim 84 words
A target substrate for a liquid crystal cell that is addressed by an eletron beam having a predetermined energy, comprising: (a) a base layer formed of material that emits secondary electrons at a first rate of emission when addressed by the beam; and (b) a coating applied to the base, the coating being formed of material that emits secondary electrons at a second rate of emission when addressed by the beam, the second rate of emission being greater than the first rate of emission.

References Cited (Backward Citations)

US3825791A Cited
US3875447A Cited
US3902096A Cited
US4131821A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-05-17 1991-11-16 1992-05-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-05-17 1995-11-16 1996-05-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-05-17 1999-11-16 2000-05-17 $7700.00 Window Closed / Lapsed

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