The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 04, 2001
Filed:
Oct. 29, 1998
William A Crossland, Harlow, GB;
Anthony B Davey, Bishops Stortford, GB;
Vincent G Geake, Thriplow, GB;
Ian D Springle, Congleton, GB;
Abstract
A liquid crystal display of the UV-phosphor type comprises a light source,for producing activation light at a predetermined narrow range of UV wavelengths, a collimator,for directing the activation light in parallel in a predetermined direction, a LC cell,formed from an array of pixels, a photoluminescent screen (,) on the cell arranged to emit a visible output when struck by the narrow-band excitation light passing through the cell, and a drive circuit for addressing the LC cell in a multiplexed manner. The direction of the light and the thickness of the cell are chosen to give the best contrast ratio for the liquid crystal. Such an effect is only possible when monochromatic, collimated light is used, which for a normal display is not practical. With the phosphor-emitter configuration, on the other hand, it is ideal, and as a result without loss of contrast a much lower range of drive voltages, and hence a much greater multiplexing capability for passive-matrix displays, can be used while preserving full viewing-angle properties of the display.