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.

Date of Patent:
Jan. 29, 1991

Filed:

Jun. 22, 1989
Applicant:
Inventor:

Kazumi Ishima, Kashiwa, JP;

Assignee:

Ricoh Company, Ltd., Tokyo, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ; H04N / ;
U.S. Cl.
CPC ...
358483 ; 358482 ; 358475 ; 358446 ; 358461 ;
Abstract

An image reader for an image forming apparatus has an array of CCD sensors in the form of chips which are arranged in a zigzag configuration along an image reading line. A reference white plate is located in association with the position of and outside of the effective image reading range of one of two CCD sensors which are situated at opposite ends of the array. The CCD sensor with which the reference white plate is associated produces a reference white signal by reading the reference white plate. The output gain of this CCD sensor is controlled on the basis of the reference white signal. The reference white signal is added to output signals of the other CCD sensors in the form of a pilot signal, whereby the output gains of the other CCD sensors are controlled.


Find Patent Forward Citations

Loading…