Patent ID: 8797552

Claim:
A scanning apparatus for generating a three-dimensional image of a surface of an object to be measured, comprising: a laser source for emitting a laser light; a first optical unit for irradiating the laser light emitted from the laser source towards the surface of the object; a second optical unit for imaging the laser light reflected from the surface of the object; a photosensitive detector having a plurality of sensor elements, for detecting an imaging position of the laser light from the second optical unit; an incident light measurement device for measuring an amount of received laser light, which corresponds to the amount of laser light entering the photosensitive detector; and a processing unit for controlling the scanning apparatus in such a way, that: a plurality of timing signals are generated having a predetermined time interval; the timing signals control a reset timing of a sensor element of the photosensitive detector; a certifying laser light is irradiated from the laser source after one timing signal for a period of time shorter than the predetermined time interval; an amount of the certifying laser light reflected from the surface of the object is measured with the incident light measurement device; and an amount of the measurement laser light emitted from the laser source is determined dependent on the amount of the certifying laser light measured with the incident light measurement device.