Laser Synchronizing Detectors - Samsung CLX-8640 series Service Manual

2. Product specifications and Description

2.7.3. Laser synchronizing detectors

The machine has two beam detector sensor boards (PD PBA). They are located at each corner of the laser optics-housing unit.
The two PD PBA detect the following :
•
[A]: Scanning start position for black
•
[B]: Scanning start position for magenta
This machine recognizes each color from the time that they are detected.
■ Main Scan Start Detection
4 beams are detected by the PD PBA at the scanning start point and create the horizontal sync (Hsync) signal. Data is
scanned by Hsync.
The arrow in the above diagram shows the data scanning direction for each color. Black (& Cyan) and Yellow (& Magenta)
use the same polygon motor scanning in opposite directions.
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