HP 4101mfp manual Optical unit block diagram

Optical unit

The optical unit consists of the optical unit chassis, the scanning lamp, the CCD driver PCB, and the optical-unit motor. When the power is turned on, the scanner controller board activates the optical-unit motor, and the unit begins to move along the rails. When the optical-unit home sensor flag (located on the bottom of the unit) aligns with the home-position sensor (located on the scanner controller board; PI1201), the unit stops in the home position.

Figure 25. Optical unit block diagram

The scanner controller board illuminates the flatbed lamp after receiving the scan command from the copy processor board. As the document is exposed to the illumination of the scanning lamp, the reflected light from the glass is sent by way of three scanning mirrors and a lens to the CCD driver PCB for image processing. When the scanning process is complete, the optical unit returns to the home position.

Figure 26. Scanning process

C9148-90909 5 Theory of operation 65