Patent · US Expired

Mark sensing device, turnable body driving device and image forming apparatus

US7526230B2 · kind B2 · utility

9Cited by
7References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 29, 2005
Grant dateApr 28, 2009
Priority date
Expiry dateMar 17, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2215/0158
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A mark sensing device of the present invention senses marks formed on a turnable body in a preselected periodic pattern in a direction of movement of the turnable body with light emitted from a light source. A slit mask is formed with slits for splitting the light emitted from the light source. A light receiving portion receives the light thus split and then incident on the mark. The slits of the slit mask each belong to either one of two regions one of which is shifted from the other by one-half of the period of the periodic pattern. The light receiving portion receives the light incident on the mark in each of the two regions and converts the light received to two electric signals. A control signal for controlling the amount of movement of the turnable body is produced from the two electric signals.

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