Laser Exposure; Sub Scanning Direction(Vertical Scanning Direction) - Epson EPL-5700 Service Manual

EPL-5700

2.1.5 Laser Exposure

An electrostatic latent image is created on the OPC drum by the laser beam
emitted from the print head. In order to count appropriate timing to print the
image, following control is performed.
PC Drum
SOS Sensor
Laser Diode
Figure 2-7. Exposure Mechanism
Rev. A
Print Head
Laser diode
Control Board
Polygon Motor

2.1.5.1 Sub Scanning Direction(Vertical scanning direction)

1. After the printer receives printing signal, the polygon motor(M2) and main
motor(M1) rotate, and paper feeding starts.
2. After the fed paper tip turns ON the paper feed sensor(/TOD signal),
main control circuit sends /VIDEO signal to the print head, and printing
starts.
3. When the print starting position moves from the first line to the second
line, it is moved down by delaying emitting time of the /VIDEO signal.
Chapter2 Operating Principles
2-6