Epson DREAMIO EH-TW2900, Service Manual

Page: 50 / 107

EH-TW3500/4500/5500 Disassembly and Assembly CONFIDENTIAL
SEIKO EPSON 50 Revision A
3.1.6 Precautions for Optical Engine and MA Board
The Optical Engine and Main (MA) Board are paired together as a single
service part. Neither is available separately. For servicing that requires the
replacement either of the MA Board or the Optical Engine, both components
must be replaced together. When sending the defected Optical Engine and
MAB set to the designated engine repair center, make sure to send all the
specified components together.
The component parts of the Optical Engine require mechanical installation
positions to be adjusted in relation to each other. In addition, the control
circuit also has its own unique characteristics, such as display signal output
drivers, that differ from projector to projector. There are also unique
differences in each optical system mechanism, such as in the light valves.
In order to obtain the optimum display, it is necessary to eliminate these
differences in electrical and mechanical characteristics as well as to make
mechanical adjustments. The various correction values are set at the time of
shipment from the factory and are stored in ROM on the MA Board.
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Do not replace either the Optical Engine or MA Board alone. (As stated
before, you cannot replace any one of the Optical Engine and MA Board, or
change the combination of them.)
„
Do not disassemble the Optical Engine. Special jigs are required for
reinstalling the optical components in the engine, such as POP Assy.,
condenser lens, mirrors. Reassembling the Optical Engine without using
the jigs are strictly prohibited.
„
Do not remove the upper guide cover of the Optical Engine. Doing so may
contaminate the internal components with dust or dirt attached to the
Optical Engine and adversely affect the image quality.
Removable screws