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:
May. 29, 2001
Filed:
Jan. 22, 1999
Applicant:
Inventor:
Satoru Ito, Yokohama, JP;
Assignee:
Ricoh Company, Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B 2/772 ; G03B 2/752 ; H01J 4/014 ; H01J 5/16 ;
U.S. Cl.
CPC ...
G03B 2/772 ; G03B 2/752 ; H01J 4/014 ; H01J 5/16 ;
Abstract
An image forming apparatus which can reduce the appearance of a vertical regist shift in a multiple beam writing system. A time interval detector is provided and is configured to detect a time interval between a start signal for scanning in a sub-scanning direction and a synchronous signal for scanning in a scanning direction. Further, this time interval is compared with at least first and second threshold values. Writing by the multiple beam sources is then controlled based on the results of the comparison. By utilizing such an operation the appearance of a vertical regist shift can be reduced.