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. 14, 1993
Filed:
Aug. 20, 1992
Katsuhiko Okitsu, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A mark detecting apparatus comprises an illuminator means for illuminating a film with marks having density different from the density of its periphery, a plurality of photosensors arranged in the feeding direction of the film, which serve as light receivers for receiving the transmitting light of the film illuminated by the illuminator means to detect the presence of marks, setting device for establishing a reference value on the basis of the maximum value and quasimaximal value among each of the output signals of the photosensors, and discriminator for discriminating the presence of marks by comparing the reference value established by the setting device and the output of the light receivers. With the structure thus arranged, it is possible to establish the binalizing reference value of the photosensors accurately even when the fluctuation of the luminous energy of the light source occurs as well as to correctly establish the reference value reliably even when the base density of the film varies.