Epson PowerLite 5000, Service Manual

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EPSON PowerLite 5000 Service Manual
3-3
Projector Lens Unit
The projector lens unit is aligned (position and mounting torque) in the factory. If the
alignment is modified, pixel divergence will occur, creating unclear images.
Electrical Corrections: Driver Board
Some parts in the mechanical section of the optical system require adjustments as
mentioned above. In the control circuit (driver board), the output driver for the display
signal is slightly different from the output driver of other devices. The mechanical
section of the optical system (e.g., light valves) must be electrically corrected. To
obtain the best images, mechanical adjustments and electric corrections must be
made. For this reason, some correction values are written to flash ROM on the driver
board before shipping. Because this factory correction is necessary to match the
optical system with the electrical system, the driver board and the optical block
(consisting of the optical head/light guide unit) make one set.
At factory shipment, the following correction data is stored in the flash ROM on the
driver board for the specified optical engine.
Gamma adjustment data
Flicker adjustment data
Ghost contrast adjustment data
Sub contrast adjustment data
A special device and skilled engineer are necessary for writing correction values,
therefore the data cannot be adjusted in the field.
3.1.5 Cautions For Field Maintenance
Observe the following procedures when you repair the projector. Otherwise,
display quality is not guaranteed, and EPSON repair service will no longer be
available.
•
Do not disassemble the optical block or loosen any screws.
•
If either the optical block or the driver board needs replacement, replace them as
a set. Also, when you send them back for repair, send them back as a set
(optical engine).
•
Because the optical block and driver board make one set, you should never
change its combination (that is, use only the new driver board with the older
parts).