PURPOSE: To facilitate adjusting operation by adjusting the fitting position of anamorphic optical element in an optical-axis direction while holding the anamorphic optical element at a constant attitude to the optical axis.

CONSTITUTION: The 1st adjusting screw 30, a coil spring 29, and a leaf spring 31 constitute the 1st operating means H1 which moves a holder 23 along a slanting surface. The 2nd adjusting screw 33 and leaf spring 31 constitute the 2nd adjusting means H2 which rotates a sliding part SP consisting of a rod material 32 and a holder stopper part 24c around an axis P1 parallel to the slanting surface. The 1st adjusting screw 30 is operated from beside in image forming optical system IF and the 2nd adjusting screw 33 is operated from in front of the image forming optical system IF.