Panasonic FP-D250 User Manual page 66

5) Driving optics unit
• The optics unit (full-speed unit and half-speed unit) is driven by the optics unit
motor.
The optics unit motor revolution drives the full-speed unit and half-speed unit
via optics unit motor belt, full-speed half-speed drive pulley, full-speed unit
drive belt and half-speed unit drive belt.
• The pulley diameter which drives half-speed unit is 1/2 of that driving the full-
speed unit, therefore, the full-speed unit moves at twice the speed of half-
speed unit so the optical path length from the original to the lens is kept constant.
• The full-speed unit is positioned at the lamp home position by the full-speed
unit position detecting plate and the lamp unit home position sensor.
• The full-speed unit holds the exposure lamp and the No.1 mirror. It scans the
original with the exposure lamp, forwards the reflected light to the No.3 mirror
via No.1 and No.2 mirrors. The image is reflected onto the CCD image sensor
after it passes through the lens.
Optics drive motor Optics drive
Half-speed unit
Full-speed unit drive belt
Half-speed unit drive belt
Pulley 1
Pulley 2
Lamp unit home
position sensor
belt
Lamp unit
Slide rail
No.2 mirror
No.3 mirror
Optics drive pulley
Belt drive shaft
Exposure lamp
No.1 mirror
CCD image sensor
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