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:
Jul. 12, 1988
Filed:
Jun. 12, 1984
James W Crimmins, Wilton, CT (US);
Other;
Abstract
An optimized full duplex light wave communication system having a base unit and a portable unit. Two continuously operative channels exist between the base and portable units for two way communication at frequencies selected to minimize interference despite the presence of light within the environment of use at both frequencies. In addition, photo emitters and sensors are specifically configured in an assembly to minimize cross talk between sensors and emitters. A closed loop is formed around the two communication channels that it is operative to regulate the intensity of illumination received at the base photo sensors to a constant level that provides quality audio communications and minimizes portable unit battery drain. The closed loop additionally causes base station transmitter frequency tracking of any center frequency variation in the portable unit receiver.