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:
Feb. 05, 2019
Filed:
May. 22, 2017
Canon Kabushiki Kaisha, Tokyo, JP;
Noriko Takeuchi, Tokyo, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
An object of the present invention is to detect the home position with a high accuracy without being affected by temperature. The present invention is an image reading apparatus having a reading portion, and the apparatus includes: an acquisition unit configured to acquire first data obtained by the reading portion reading a main scanning line in a state where a light source of the reading portion is turned on in a first light quantity, and second data obtained by the reading portion reading the main scanning line in a state where the light source of the reading portion is turned on in a second light quantity smaller than the first light quantity; a generation unit configured to generate difference data by subtracting the value of the second data from the value of the first data; and a determination unit configured to determine whether a mark arranged at a position corresponding to a home position of the reading portion has been detected on the main scanning line based on the difference data.