Ricoh G031 Service Manual page 51

LASER EXPOSURE
The optical path from the laser diode to the drum is shown on the previous page.
The LD drive board [C] outputs the laser beam to the polygonal mirror [A] through
the cylindrical lenses [B], which focus the laser beam.
G031
The laser beam goes to the F-theta mirror [F], 1st mirror [H] and BTL [G]. Then, the
beam reaches the drum [D] through the shield glass [K].
The beam reflected by the polygonal mirror writes the pixels of the latent image on
the drum. The F-theta mirror [F] ensures constant intervals between the pixels. The
BTL [G] corrects for irregularities in the polygonal mirror faces.
The laser synchronization detector [J] synchronizes the start of the main scan.
G032
The G032 has a shorter beam path than the G031.
The beam which is reflected by the polygonal mirror goes to the F-theta lens [I].
The beam reaches the drum [D] through the shield glass [K]. The F-theta lens [I]
does the functions of both the F-theta [F] mirror and the BTL [G].
The LD drive board for the G032 contains the laser synchronization detector.
SM 2-7 G031/G032