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:
Sep. 01, 1992
Filed:
Feb. 07, 1991
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
An illumination type optical recorded information reading device including a plurality of light emitting elements, a photo detector for detecting optical indication on a media and converting the detected indication to electrical information, a plurality of driving elements for driving the light emitting elements, a driving current detector for detecting a total value of driving currents flowing through the driving elements, and a controller for comparing the total value with a reference value and generating a control signal to the driving elements so as to make a difference between the total value and the reference value constant. Further, a distribution of an illuminance of the light to be applied to the media is set in such a manner that the illuminance at positions spaced away from a central portion of a maximum detectable range of the photo detector is higher than that at the central portion, and that the illuminance at opposite end portions of the maximum detectable range is lower than that at the positions spaced away from the central portion.