Konica Minolta bizhub C658 Service Manual page 1791

bizhub C658/C558/C458/C368/C308/C258
3.3 Operation
3.3.1 Overview
• The surface of the photo conductor is irradiated with a laser light and an electrostatic latent image is thereby formed.
• The PH unit has a four color exposure unit single-piece configuration. A semiconductor laser is provided for each of four different colors. A
single polygon motor is used to make a scan.
• The polygon mirror has seven faces.
• A rotating polygon mirror is irradiated with a laser light emitted from the laser diode on the laser drive board to let the laser light scan.
• bizhub C658/C558 models are equipped with a 2-beam-array laser diode. With two laser beams emitted from these two elements arranged
vertically, two lines are scanned through a single face of the polygon mirror.
• bizhub C458/C368/C308/C258 models are equipped with a single-beam-array laser diode. Single line is scanned through a single face of
the polygon mirror.
2-beam laser image view
Y
[1]
[11]
[7]
[8]
[6]
[1] Photo conductor Y
[3] Photo conductor rotation direction
[5] G1 lens
[7] Laser diode
[9] G2 lens
[11] Photo conductor
3.3.2 Laser exposure process
(1) bizhub C368/C308/C258
1. The laser light of each color enters the cylindrical lens via the synthetic mirror and return mirror (light source).
2. At the cylindrical lens, each laser light is condensed in the vicinity of the polygon mirror.
3. Since the angle of incidence for each color of laser light varies, the laser light reflected by the polygon mirror is reflected in a different
angle for each color.
4. The condensing angle of each color of laser light is corrected by the G1 and G2 lenses and then reaches each return mirror.
5. The K laser light is condensed on the photo conductor surface via the G3 lens and return mirror1. The Y laser light is condensed on the
photo conductor surface via the return mirror1, G3 lens, and return mirror2. The M laser light is condensed on the photo conductor
surface via the return mirror1, G3 lens, and return mirror2. The C laser light is condensed on the photo conductor surface via the return
mirror1, G3 lens, return mirror2, and return mirror3.
O THEORY OF OPERATION bizhub C658/C558/C458/C368/C308/C258 > 3. WRITE
M C
[12]
[10]
[9]
[4]
[5]
K
[2]
[3]
[2] One line, two scan
[4] Return mirror1
[6] Polygon mirror
[8] Return mirror3
[10] Return mirror2
[12] Beam
O-16
SECTION (PH SECTION)