2-31
Sub
Assemblies
(2) Semiconductor Laser
• The laser beams that emanate from two semiconductor lasers are turned ON/
OFF by turning the current flow to the semiconductor lasers ON/OFF with a
digital signal that corresponds to the image to irradiate the drum.
The semiconductor laser is switched ON/OFF in accordance with the image
data. (Image data for the letter P.)
– Semiconductor laser is ON.
– Semiconductor laser is OFF.
(3) Collimating lens
• Converts divergent light of the semiconductor laser to parallel light so that
scanning is stabilized and light spot convergence is improved.
(4) Polygon scanner
• The polygon scanner consists of 6 sided pillar-shaped rotary mirrors that convert
the laser beam into a scanning beam. In regard to the performance of high
resolution recording, the uneven speed of scanning lines reflected from each
mirror face, the difference in inclination of each reflecting face (surface inclination
error) against the rotary shaft, and the rise time during activation become
important performance elements.
Semiconductor laser
Collimator lens
Polygon scanner
Hexagonal mirror
