Light-beam deflecting apparatus, manufacturing method of light-beam deflecting apparatus and image-forming apparatus

摘要

The invention concerns light-beam deflecting apparatus in which a polygon mirror is pushed against a flange to hold it stationary. The light-beam deflecting apparatus includes a base member; a polygon mirror being rotatable in respect to the base member; a flange contacting the polygon mirror to hold the polygon mirror; and pushing member to push the polygon mirror against the flange. One or both of contacting surfaces of the polygon mirror and the flange is/are finished to a surface roughness of Ry, which fulfills a first formula of Ry>=3 mum or a second formula of 3 mum<=Ry<=20 mum.