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. 05, 2009
Filed:
Feb. 06, 2004
Yoshiaki Kawai, Kanagawa, JP;
Yoshiaki Kawai, Kanagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An image forming apparatus using a synchronization signal generator can easily generate a pixel clock that enables both a magnification correction in a main scanning direction and a correction of expansion and contraction of pixel width in the main scanning direction. Each of pixel clock generation units generates a clock signal by dividing a frequency of a high-frequency clock so as to generate pulses of a reference period, a long period longer than the reference period and a short period shorter than the reference period, and outputs, as the pixel clock, one of the pulses that is designated by an output selection signal. A pixel clock correction data synthesizing unit synthesizes a first selection signal, which is generated base on a time-series distribution of the pulses of each period defined by a first set of data, and a second selection signal, which is based on a time-series distribution of the pulses of each period defined by a second set of data, so as to generate the output selection signal.