Patent ID: 8736655
Filing Date: 2014-05-27
Classification: B41J,G03G

Abstract:
1. A light scanning unit, comprising: a light source configured to emit a light beam; a beam deflector configured to deflect and to scan the light beam emitted from the light source along a main scanning direction; a scanning optical system configured to receive a first portion of the light beam that is deflected and scanned by the beam deflector to form an image on a scanning surface with the received first portion of the light beam; a beam detection mirror disposed between the beam deflector and the scanning optical system, to change a direction of an optical path of a second portion of the light beam toward a beam detection sensor; and a beam detection sensor configured to receive the second portion of the light beam that is deflected and scanned by the beam deflector, without passing through the scanning optical system, to generate a synchronization signal based on the received second portion of the light beam, the synchronization signal being generated by photoelectrically converting the light beam incident on the light incident surface area and output via at least two output terminals, wherein the beam detection sensor includes a light receiving surface upon which the received second portion of the light beam is incident and the at least two output terminals that are arranged outside a scanning path of the received second portion of the light beam on the light receiving surface, and where the at least two output terminals are spaced apart from each other by a predetermined distance on the light receiving surface that is greater than the scanning path of the received second portion of the light beam between the at least two output terminals.