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US4289383A Expired / Lapsed US ⏱️ 0.0 years remaining

Lighted dot matrix display

Assignee: Timex Group USA Inc
•
Filing: 1979-09-04
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Granted: 1981-09-15
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Expires: 1999-09-04
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Abstract

Abstract A dot matrix display of the liquid crystal type operative in either transmissive or reflective modes includes means to illuminate the back of the display, and means for electrically reversing the image on the display from dark on a light background to light (transparent) on dark background for transmissive viewing when the effective light intensity of the illuminating means is greater than the effective ambient light intensity on the front of the display.

Inventors

  • 👤 Jack Schwarzschild

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 12:10
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/36; G09G3/3611; G09G3/3622; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133626; G09G2300/00; G09G2300/04; G09G2300/0439; G09G2300/0456; G09G2320/00; G09G2320/06; G09G2320/0606; G09G2320/066; G09G2340/00; G09G2340/14; G09G2360/00; G09G2360/14; G09G2360/144

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 91 words
In an electrooptic display of the type operable to provide an image viewable either in the transmissive or reflective modes, with means to selectively activate a plurality of electrooptic segments to provide said image, the improvement comprising: illuminating means disposed to provide light at the back of said display when it functions in a transmissive mode, said illuminating means comprising an incandescent backlight, image reversal means for electrically reversing the image on said display, and, a manually actuated switch connected to simultaneously actuate said image reversal means and said illuminating means.
Claim 2
Dependent Claim 91 words
In an electrooptic display of the type operable to provide an image viewable either in the transmissive or reflective modes, with means to selectively activate a plurality of electrooptic segments to provide said image, the improvement comprising: illuminating means disposed to provide light at the back of said display when it functions in a transmissive mode, said illuminating means comprising an incandescent backlight, image reversal means for electrically reversing the image on said display, and, a manually actuated switch connected to simultaneously actuate said image reversal means and said illuminating means.
Claim 3
Dependent Claim 59 words
The combination according to claim 1, wherein said display is a dot matrix liquid crystal display having groups of row and column segments addressed and multiplexed to provide an image, and wherein said image reversal means comprises a control gate adapted to reverse the polarity of the voltage applied to one of said groups of row or column segments.

References Cited (Backward Citations)

US4104627A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-09-14 1985-03-16 1985-09-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-09-14 1989-03-16 1989-09-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-09-14 1993-03-16 1993-09-15 $7700.00 Window Closed / Lapsed

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