Patent ID: 6798548
Filing Date: 2004-09-28
Classification: G01C

Abstract:
A rotational laser apparatus comprising:a light emitting part for emitting scanning laser beam toward a target having reflected sections; a rotated part for forming a reference plane with the scanning laser beam from the light emitting part; an oblique mechanism for causing the rotated part to oblique; a light receiving part for receiving light reflected on the target; and a control part for controlling the oblique mechanism according to a light-receiving signal of the light receiving part, said target being provided with a plurality of reflected sections transverse to the scanning laser beam, said reflected sections being disposed in such a manner that a time series arranging state for pulses of the light receiving signal differs between a case that the scanning laser beam intersects the reflected planes from one side to the other side and a cases that the laser beam intersects the reflected sections from the other side to the one side, with an identical scanning direction of the scanning laser beam, said control part including a judging circuit for judging an operated direction of the oblique mechanism based on the time series arranging state for pulses of the light receiving signal.