Light Engine and Optical Block are the same thing ... just different names. It's listed twice many times so that it's easier to search on the web. Hopefully Hitachi will do something about it some day. I plan on letting everyone out there know about it so we can all go after Hitachi. There is a Suit filed against them for the 50v500 set that has the same types of problems ... perhaps it will cover the problems with the 50v710 also. Hitachi did absolutely nothing to help me with the problem. I had to find the part and fix it myself.
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