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. 18, 1992
Filed:
Mar. 13, 1991
Minoru Ohshima, Ibaraki, JP;
Susumu Saitoh, Ibaraki, JP;
Masami Ishikawa, Ibaraki, JP;
Tsukasa Ogawa, Ibaraki, JP;
Kazutoshi Obara, Ibaraki, JP;
Hitachi Koki Co., Ltd., Tokyo, JP;
Abstract
A double beam scan type optical apparatus for use in a laser printer or the like. Such apparatus comprises two light sources and a lens system which provide scanning means for scanning a surface with parallel output light beams of the two light sources and beam distance controlling means for controlling the distance between the light beams. The reliability of the invention is improved by monitoring the intensity of the beams. Beam intensity checking means provide signals to verify that the intensity of each beam is maintained equal thus assuring that no abnormal conditions exist with the light sources or the lens system of the apparatus.