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:
Dec. 15, 1987
Filed:
Oct. 08, 1986
Shunju Anzai, Nara, JP;
Hiromu Sasaki, Yamatokoriyama, JP;
Norihide Kunikawa, Yao, JP;
Kazuyuki Ohgita, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A document size detection apparatus having a plurality of sensor portions including light emitting devices and photodetector devices disposed in the vicinity of an original table for detecting the size of a document such as an original mounted on the original table is disclosed. This apparatus uses reflected light or transmitted light, a comparator for comparing the output level of the sensor portion with a reference level, and decision means for deciding the document size depending on the output signal of the comparator. The document size detection apparatus comprises a circuit for changing the reference level of the comparator and for detecting the resultant output of the comparator in order to find the condition in which the reference level becomes equal to the output level of the sensor portion and a storage circuit for storing the value representing that condition, which are used in the adjustment mode without a document mounted on the original table, and a reference level setting circuit for setting the reference level to be input to the comparator depending on the value stored in the storage circuit, which is used in the document size decision mode for detecting the size of a document mounted on the table.