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:
Nov. 05, 1985
Filed:
Aug. 24, 1984
Demetris E Paraskevopoulos, Pittsford, NY (US);
Xerox Corporation, Stamford, CT (US);
Abstract
The present invention is an apparatus for monitoring toner concentration on a photoreceptor surface. The apparatus includes a light emitting diode, the phototransistor, a beam splitter, and a lens disposed between the beam splitter and the photoreceptor surface to collimate the light beam between the lens and the photoreceptor surface. A portion of the light emitted from the LED is transmitted through the beam splitter and the lens to the photoreceptor surface. Collimated light is reflected from the photoreceptor surface back through the lens and reflected from the beam splitter to the phototransistor. The output signal from the phototransistor because of the incident and reflected collimated light is independent of the distance of the lens from the photoreceptor surface. Alternately, a second lens is disposed between the beam splitter and the phototransistor to enhance overall resolution.