An information recording apparatus for recording image information on an image forming body, the apparatus including: a light source for emitting light; a light valve of diffraction grating type, for modulating the light emitted from the light source according to the image information, the light valve comprising a plurality of ribbons arranged in an array; and an optical section for forming an image on the image forming body with the light diffracted and modulated by the light valve, wherein a longitudinal direction of the ribbons of the light valve is arranged at a specific angle with respect to a direction perpendicular to the array direction of the ribbons.