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. 19, 1989
Filed:
Jun. 16, 1988
Yasuo Abuyama, Ebina, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
An image forming apparatus according to this invention, for example, a digital copying machine, comprises an original scanning section, which includes an exposure lamp for exposing the image of an original, a lens unit which can change an image forming magnification when forming the image of the original exposed by the lamp and mirror unit, a photoelectric converter on which an image corresponding to the original image is formed by the original scanning section and which converts the formed image into an electric signal, a main controller for subjecting the electric signal to a predetermined signal processing to electrically change its magnification, and an image forming section for receiving and subjecting the processed signal to another predetermined signal processing to form an image on a sheet which corresponds to the original image. A focal length error of the lens unit caused in the production line is measured in advance, and, based on this measuring result, an error of the original scanning section is stored as compensation data in a non-volatile memory. At the time of changing the magnification of said electric signal by means of the original scanning section and the signal processing, the main controller reads out the compensation data from the memory and compensates for the error of the original scanning section based on this compensation data.