Specifications

3. LASER EXPOSURE
3.1 OVERVIEW
This machine uses a laser diode to produce electrostatic images on an OPC
drum. The laser diode unit converts image data from the BICU board into
laser pulses, and the optical components direct these pulses to the drum.
To produce a high quality copy image, these are 64 gradations for the laser
pulses, controlled through power modulation and pulse width modulation.
Exposure of the drum by the laser beam creates the latent image. The laser
beam makes the main scan while drum rotation controls the sub scan.
The strength of the beam is 0.6 mW on the drum surface at a wavelength of
780 nm.
There are four polygon motor speeds:
Resolution (dpi) Modes Motor Speed (rpm) Data Frequency (MHz)
400 dpi Copy, Fax, and Printer 14173.23 9.276
600 dpi Printer 21259.84 20.872
391.16 dpi Fax (Image rotation) 13860.00 9.216
406.4 dpi Fax (mm printing) 14400.00 9.216
LASER EXPOSURE 1 August 1996
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