Polygon mirror, deflecting apparatus, image forming apparatus and method of manufacturing the polygon mirror

摘要

There is provided a polygon mirror comprising a mirror body shaped in a regular polygon and having circumferential surfaces, a top surface and a bottom surface, a reflection surface formed on each of the circumferential surface, a machining reference surface provided on one of the top and bottom surfaces, machined to form a mirror surface and used as a reference surface for machining the reflection surface on each of the circumferential surfaces and an assembling reference surface provided on one of the top an bottom surfaces, shaped in parallel to the machining reference surface, machined to form a rough surface and used as a reference surface for assembling the polygon mirror. The polygon mirror has a high degree of reliability in terms of stable optical characteristic when a polygon mirror and a flange member are bonded with each other.