Patent ID: 7557976

Claim:
A light scanning apparatus, comprising: a light source which emits a light beam; a deflector which includes an oscillation mirror which oscillates about an oscillatory axis which is orthogonal or approximately orthogonal to a main scanning direction, and deflects the light beam emitted from the light source using the oscillation mirror to make the light beam scan a scanning region in the main scanning direction; a detector which outputs a detection signal when the scanning light beam, which moves in the scanning region, is detected; and a controller which controls a mirror drive signal fed to the oscillation mirror based on the detection signal outputted from the detector and accordingly adjusts an amplitude of the oscillation mirror, wherein the controller stops driving the oscillation mirror when the controller determines that the detection signal is not outputted from the detector, even though the light source is turned on to emit the light beam, wherein the controller detects a change of the amplitude of the oscillation mirror in accordance with the detection signal which the detector outputs when detecting a reciprocal light beam which moves forward in the scanning region via the detector and moves backward in the scanning region via the detector.