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:
Oct. 07, 1980
Filed:
Dec. 14, 1978
John M Vandling, Pleasantville, NY (US);
Exxon Research & Engineering Co., Florham Park, NJ (US);
Abstract
A facsimile transmitter detects dark-light variations in an illuminated document by means of a photodetector. After amplification, the output from the photodetector is applied to a threshold detector generating a multilevel digital signal. When the magnitude of the amplified photodetector signal is greater than one fixed threshold level, one level of the digital signal is generated. When the magnitude of the amplified photodetector signal is less than another fixed threshold level, another level of the digital signal is generated. When the magnitude of the amplified photodetector output lies between the two threshold levels, one level of the digital signal is generated when the peaked, amplified photodetector signal is greater than the unpeaked amplified photodetector signal and the other level of the digital signal is generated when the peaked amplified photodetector signal is less than the unpeaked, amplified photodetector signal. The threshold detector output is utilized to control a carrier modulator which generates signals for transmission to a remotely located receiver through a communications link.