| 摘要 |
PURPOSE:To obtain a scanner which causes less windage loss even if it is applied to an inexpensive rotary polygon mirror with a few facets and which can rotate silently by providing a windshield plate with a radius longer than that of the reflection facets of the rotary polygon mirror on the opposite side of a coreless stator/armature. CONSTITUTION:The windshield disk-like body 13 is intended to rotate and send an air layer around the reflection facets 12a together with the rotation of the rotary polygon mirror 12. Therefore, the body 13 is formed to obt. the radius longer than that of the rotary polygon mirror 12. It is has only a few facets, the air layer which cannot escape from the reflection facets 12a rotates along with the rotation of said mirror 12. Accordingly wind resistance becomes small, compared with a case without the windshield dislike body 13. Thereby, sound caused by the high speed rotation of the mirror 12 is minimized, and the rotary polygon mirror scanner 1 can rotate silently. |
