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. 15, 1988
Filed:
Feb. 20, 1987
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
In an optical media monitoring device that detects presence of light-interrupting media between a photoemitter component and a photoreceptor component provided to operate in cooperation with each other, the photoemitter component is driven at a variable level of light emission, and a comparator compares the output of the photoreceptor component with a reference signal which is also variable. The driving means is controlled to cause the photoemitter component to emit a level of light lower than normally used for media detection. Dust degradation of the sensor is determined by checking, in a state of no media present and the reduced light emission of the photoemitter component, whether the output of the photoreceptor component is greater than the reference signal level.