Patent ID: 8154784

Claim:
An optical scanning device comprising: a light beam generating unit configured to generate a light beam; a light beam deflecting unit configured to receive the light beam and deflect/emit the light beam with a deflecting mirror; a light beam ON/OFF control unit configured to control the light beam generating unit so that the light beam deflected by the light beam deflecting unit is turned ON/OFF in a particular optical scanning range while the light beam is being reciprocally scanned; and a light beam scanning time measuring unit configured to obtain a measurement value by measuring a time or time intervals at which the light beam passes a reference point while being reciprocally scanned, the reference point being provided at an arbitrary position on an edge part of an entire light beam scanning region that is away from a center part of the entire light beam scanning region, wherein: timings at which the light beam is turned ON/OFF are controlled in accordance with the measurement value.