Epson EMP-7300 Service Manual page 68

4. Projection lens unit
The alignment of the projection lens unit is applied (position and fixing torque) in
our factory. If the alignment is modified, clear image will not be made, because of
the pixel divergence.
Electrical corrections (CD10DR board)
Some parts in the mechanical section of the optical system require some
mechanical adjustments mentioned above. In the control circuit (CD10DR board),
the output driver for the display signal is slightly different from the output driver of
other device (CD10DR board) in individuality. The mechanical section itself of the
optical system (e.g. light valves) must be electrically corrected. Therefore to obtain
the best image, not only the mechanical adjustment but the electric correction is
required. For this reason some correction values are written to Flash ROM of the
CD10DR board on factory shipping. For matching the optical system and electrical
system, the electric correction is necessary. Consequently, the CD10DR board
and the optical block (consists of optical head / light guide unit) make one set.
At the factory shipment, following correction data are stored in the Flash ROM on
the CD10DR board according to the specified optical engine.
Gamma adjustment data
Flicker adjustment data
Ghost contrast adjustment data
Sub contrast adjustment data
For the writing correction values, an expensive, special device and also skillful
engineer are necessary, therefore it can not adjust in the field.
Caution for field maintenance
Observe the following procedure, when you repair. Otherwise, display quality is
not guaranteed, and also EPSON repair service is not available.
1). Do not disassemble the block. (Do not loosen any screws.)
2). If either the optical block or the CD10DR board becomes wrong, replace
them in set. And when you send back them to us for repair, send back
them in set (by optical engine).
3).The optical block and the CD10DR board make the optical engine set, so
never change its combination (e.g. use only the CD10DR board for the
other repair parts).
REV.A
3-3