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:
May. 05, 1981
Filed:
Feb. 23, 1979
Waldemar Greubel, Munich, DE;
Hans Krueger, Munich, DE;
Siemens Aktiengesellschaft, Berlin & Munich, DE;
Abstract
A display device includes a light valve that is operated in a time division multiplex method and a fluorescent plate. The light valve may be a liquid crystal with a steep gradient of the contrast-voltage curve so that more multiplex steps are possible. One method of increasing this gradient is to allow only light from a narrow defined spatial angle range to pass through the light valve. In order to produce the narrow light cone that is desired, the invention proposes utilizing a diffusingly reflective layer, which extends parallel to a surface of the fluorescent plate at a finite distance and preferably, the light outlet or exit window of the plate is a surface provided with a dielectric multiple layer which allows the fluorescent light to emerge only in relatively limited spatial angle range. Preferably, these surfaces are the narrow edges of the fluorescent plate.