LASER SCANNING UNIT

摘要

PURPOSE: A laser scanning unit is provided to save a manufacturing cost by using a reflection film stuck to a reflection face for reflecting laser beam to a photo sensor. CONSTITUTION: A laser diode(30) emits laser beam. A collimator lens(31) collimates the laser beam. A polygon mirror(33) migrates the laser beam in a uniform line speed of horizontal direction for scanning. An f-theta lens(36) refracts the laser beam toward a main scanning direction to correct an aberration. A reflection film(38) stuck to a reflection face(41) reflects the laser beam toward horizontal direction. A photo sensor(37) receives the laser beam reflected in the reflection face(41). A base plate supports the reflection face(41) and the photo sensor(37).