MULTIBEAM ALIGNER

摘要

An aligner which is an improvement to a multibeam aligner which scans an object with a plurality of beams, and which reduces deviations between respective beams to superpose images accurately and eliminates color misregistration or fading and blur of a line drawing. The multibeam aligner has an optical device which changes an exit angle from a main scanning direction in accordance with the fluctuation of a wavelength which is caused by the change of the temperature of a laser beam from a light source and can shift a :beam position by a length equal to a positional deviation length generated by a focusing lens in accordance with the difference in wavelength in a direction opposite to the direction of the deviation in a light path between the focusing lens between a light deflector and an image plane and a horizontal synchronism detection photodetector, wherein, even if the wavelength of a light beam from a light source which emits two laser beams for the respective colors of separated color components fluctuates owing to a temperature change, the light beam can be guided to the same position on the detection surface of a horizontal synchronism detection photodetector.