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:
Aug. 16, 1988
Filed:
Aug. 18, 1986
Hilmar Franke, Bramsche, DE;
Fritz R Gfeller, Ossining, NY (US);
IBM Corporation, Armonk, NY (US);
Abstract
A fluorescent activated light detector for detection of time modulated IR signals of preselected wavelength includes an IR light collecting member made of a solid transparent core material with a fluorescent light absorbing dye molecularly dispersed throughout the core. Photodiodes are operatively associated with the collecting member for detecting fluorescent light emitted by the collecting member upon exposure to incident IR radiation of the preselected wavelength. The light collecting member has a surface area A1 much greater than an active area A2 of the photosensing means. Use of this fluorescent activated light detector allows for increasing the effective transmission distance of infrared free space communication links without requiring an increase in transmitter radiated power.