LIGHT DEFLECTOR, IMAGE EXPOSURE DEVICE AND IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a light deflector capable of obtaining a stable rotational performance at rotating at a high speed by miniaturizing a rotary polygon mirror and improving the attaching accuracy. SOLUTION: A flange member 23 which is stuck and fixed to at least one of the end face of the rotary polygon mirror 22 and the outer peripheral surface of an outer cylindrical member 21 is provided with a reference flat part coming into contact with the end faces of the rotary polygon mirror 22 and a projecting edge part 23c whose outside diameter is larger than that of the rotary polygon mirror 22, and the reference flat part of the flange member 23 comes into contact with the internal side of the inscribed circle of the polygon formed on the end faces of the rotary polygon mirror 22, and the surface coming close to the reflection mirror surface of the rotary polygon mirror 22 of the projecting edge part 23c is formed to an inclined surface so that it may be away from a laser beam L made incident/exit on/from the rotary polygon mirror 22 from the reference flat part up to the outer periphery, and a rotary driving magnet 24 is fixed on the other end face of the projecting edge part 23c.