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US4881798A Expired / Lapsed US ⏱️ 0.0 years remaining

Thermal optical modulation method and device using alternating current

Assignee: Canon Inc
•
Filing: 1989-04-14
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Granted: 1989-11-21
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Expires: 2009-04-14
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Abstract

Abstract An optical modulating method is provided which comprises heating a heat-sensitive medium comprising a polymeric substance and a liquid with a heat-generating resistor adjacent to the medium, thereby modulating the light incident on the medium at the heated region. The liquid may be heated to the critical solution temperature or higher of the constituent polymeric substance.

Inventors

  • 👤 Satoshi Yuasa
  • 👤 Hirohide Munakata
  • 👤 Yoko Yoshinaga
  • 👤 Masahiro Haruta
  • 👤 Yukuo Nishimura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 01:59
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/0147

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 55 words
An optical modulating device comprising a heat-sensitive medium containing a polymeric substance and a liquid; a heat-generating resistor a protecting layer provided between said heat-sensitive medium and said heat-generating resistor; and means for supplying an alternating electric current with a frequency of 200 to 800 Hz to said heat-generating resistor for heating said heat-sensitive medium.
Claim 2
Dependent Claim 55 words
An optical modulating device comprising a heat-sensitive medium containing a polymeric substance and a liquid; a heat-generating resistor a protecting layer provided between said heat-sensitive medium and said heat-generating resistor; and means for supplying an alternating electric current with a frequency of 200 to 800 Hz to said heat-generating resistor for heating said heat-sensitive medium.
Claim 3
Dependent Claim 17 words
An optical modulating device according to claim 1, wherein said polymeric substance is a crosslinked polymeric substance.
Claim 4
Dependent Claim 17 words
An optical modulating device according to claim 1, further comprising cooling means for cooling said heat-sensitive medium.
Claim 5
Dependent Claim 38 words
An optical modulating device according to claim 3, wherein said cooling means maintains the polymeric substance in said heat sensitive medium at a temperature lower than the critical dissolution temperature thereof when said heat-sensitive medium is not heated.
Claim 6
Dependent Claim 27 words
An optical modulating device according to claim 1, wherein the alternating current supplying means supplies an alternating current which is not overlapped with a direct current component.
Claim 7
Dependent Claim 17 words
An optical modulating device according to claim 1, wherein said heat-sensitive medium undergoes phase transition when heated.
Claim 8
Dependent Claim 25 words
An optical modulating device according to claim 1, wherein the heat-sensitive medium is a thin layer having a thickness of 1 μm to 1000 μm.
Claim 9
Dependent Claim 27 words
An optical modulating device according to claim 1, wherein the polymeric substance is contained in the heat-sensitive medium at a proportion of 0.2 to 25% by weight.
Claim 10
Dependent Claim 87 words
An optical modulating method, which comprises the steps of heating a region of a heat-sensitive medium by use of a heat-generating resistor, said medium comprising a polymeric substance and a liquid, and a protecting layer being provided between said medium and said heat-generating resistor, supplying an alternating electric current with a frequency of 200 to 800 Hz to said heat-generating resistor to generate heat, and impinging light on said heated heat-sensitive medium, thereby modulating the light which is incident on said medium at the heated region thereof.
Claim 11
Dependent Claim 87 words
An optical modulating method, which comprises the steps of heating a region of a heat-sensitive medium by use of a heat-generating resistor, said medium comprising a polymeric substance and a liquid, and a protecting layer being provided between said medium and said heat-generating resistor, supplying an alternating electric current with a frequency of 200 to 800 Hz to said heat-generating resistor to generate heat, and impinging light on said heated heat-sensitive medium, thereby modulating the light which is incident on said medium at the heated region thereof.

References Cited (Backward Citations)

US4025163A Cited
US4169661A Cited
JPS54334A Cited
US4260225A Cited
US4561718A Cited
US4711830A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-11-20 1993-05-22 1993-11-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-11-20 1997-05-22 1997-11-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-11-20 2001-05-22 2001-11-21 $7700.00 Window Closed / Lapsed

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