<p>The waveguide type optical deflector is provided with appts for deflecting guided light waves on a plane parallel with the waveguide path, and a grating disposed slantwise with respect to the direction perpendicular to the transmission direction of the guided wave on the surface of or inside of the waveguide path as a light outputting part. The appts deflects light waves toward the outside of a plane parallel with the optical waveguide path by the grating.</p>
