| 摘要 |
PROBLEM TO BE SOLVED: To suppress the temperature rising of a deflector which is provided with a polygonal mirror which deflects a light beam from a light source to a subscanning direction, a motor which rotates the mirror, and a circuit which drives the motor and is installed on the internal bottom face of a housing of a scanning optical device without using any complicated structure nor increasing the number of parts. SOLUTION: An opening section 5 is formed at the bottom section of a housing 10 to be matched with the shape of the substrate 18 of a deflector 4 and, at the same time, a step section 6 is formed so as to border the opening section 5 and the deflector 4 is put on the step section 6 and fixed. The driving power section of a motor 15b and the circuit element of a driving circuit, both of which are the heat source of the deflector 4, are aggressively brought into contact with the outside air by exposing hem from the enclosure 10 and, at the same time, the inside of the enclosure 10 is blocked from the heat source side with the substrate 18. Therefore, the temperature rising of the deflector 4 can be suppressed and, at the same time, the intrusion of heat into the enclosure 10 can be suppressed effectively. |
