| 摘要 |
PURPOSE:To obtain the rotary polygon mirror whose surface accuracy is high and whose rotary part is well-balanced by forming as one body a multiprismatic shape part by using a base material of a multiprismatic shape of a resin whose rigidity has been raised and a reflexing surface member of a resin whose working accuracy is high. CONSTITUTION:A base material 1 consists of a regular multiprismatic cylinder shape, and in its inside, a through-hole boss 6 is fixed and coupled to the base material by plural ribs 7. Also, it consists of a resin, and a stiffening material of a glass fiber, a carbon fiber, etc., is mixed in order to raise the rigidity. A reflecting surface member 2 consists of a resin whose cuttability is high such as PMMA, ABS, polycarbonate, etc., and brought to mold forming as one body with the base material 1. An increase reflecting film 3 is a metallic film formed by vapor-depositing aluminum, copper, etc., onto the reflecting film, and by attaching a protective film 4 thereto, its reflection factor is raised. In such a way, the surface accuracy can be raised, the rotary polygon mirror can be made light in weight, and the rotary part is well-balanced. |
