Patent · US Expired

Image forming apparatus

US6049351A · kind A · utility

8Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 15, 1998
Grant dateApr 11, 2000
Priority date
Expiry dateMay 15, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B26/127
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

It is an object to stably form a color image of a high quality without a color deviation by completing a phase adjustment in a short time so that a reference signal of a main scanning control system and a reference signal of a sub scanning control system have a predetermined phase. To accomplish the object, an output timing of an ITOP signal which is generated by a sensor 9 which detects a predetermined position of a photosensitive drum 5 which is rotated is compared with an output timing of a virtual main scanning sync signal BD' of a polygon mirror 3 for scanning a light beam onto the photosensitive drum 5 in the main scanning direction, thereby deciding an output timing of a reference clock SP. On the basis of the decided output timing, a PLL circuit 116 controls a rotational speed of a polygon motor 117 so that a difference between the reference clock SP which is outputted by a counter 83 and the ITOP signal have a predetermined phase difference.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.