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:
Feb. 05, 1991
Filed:
Dec. 13, 1988
John L Beiswenger, Salem, WI (US);
Technomarket, Inc., Buffalo Growe, IL (US);
Abstract
An apparatus for providing a control signal utilizes a liquid crystal panel and means for transiently forming transparent windows therein. There is a source of electromagnetic radiation (EMR) adjacent the panel and positioned to pass EMR through transiently open windows. There is an EMR detector positioned adjacent the source and a defined EMR path between the source and detector which path is formed in response to a transiently open window and includes an area for the positioning of an object to occlude the EMR radiation passing between the source and detector. The path also includes a reflector which directs EMR from the source back in the same general direction to the detector. There is a timing and logic circuit correlating the opening of the transient windows and the detection of EMR at said detector to provide a control signal.