To obtain a multibeam type scanning system in which a spin element or a wobbling element is not needed for rotating beams of one or more of multibeams by providing at least one acoustic optical element actuatble so as to deflect at least one beam with respect to the spin axis line of a spin deflector.

A laser light beam from a first laser oscillator 105 is directed toward a first optical path toward an acoustic optical modulator(AOM) 115 arranged at the upstream of a spin deflector. This AMO 115 performs the modulation of a first beam before the beam passes a focusing lens 125 and a collimating lens 130. Moreover, a second laser oscillator 1110 is present in this system and an AOM 120 modulates a second beam independently. Then, these two beams scan on a curved image surface 165 without the spin element or the wobbling element in order to provide multiple scanning lines which do not intersect each other on the curved image surface 165.