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:
Apr. 28, 1981
Filed:
Jul. 06, 1979
Guenther Baur, Freiburg, DE;
Hans Krueger, Munich, DE;
Fritz Windscheid, Freiburg, DE;
Volker Wittwer, Freiburg, DE;
Siemens Aktiengesellschaft, Berlin & Munich, DE;
Abstract
An indicating device having an electro-optical light valve unit such as in a liquid crystal cell arranged behind a plate containing fluorescent particles characterized by a contrast filter disposed behind the plate and unit in the direction of viewing and a reflector disposed behind the contrast filter. The contrast filter will pass light of the spectrum which excites the fluorescent particles of the fluorescent plate but absorbs the emitted fluorescent light and a majority of the other light so that a background is either dark or of a specific color. The energized light valves cause a bright image on the dark or colored background.