An optical scanning apparatus which has a scanning position detecting section
in which a plurality of light receiving sensors are arranged at predetermined spaces
in a direction substantially perpendicular to the scanning direction without being
overlapped in the scanning direction and each of the light receiving sensors has
a shape in which a side into which scanning light of a laser beam is entered is
substantially perpendicular to the scanning direction, an opposite side is slanted
with respect to the scanning light, and at least one of recess is provided to the
slanted side, and it is detected that pulse widths of respective output signals
obtained by scanning the scanning position detecting sensor composed of the light
receiving sensors with the scanning light of the laser beams are smaller than a
predetermined pulse width, so that the resolution in the sub scanning direction
of the lasers can be easily adjusted with a simple algorithm.
