Bravo, you've made more progress than I have.

I understand that orientation can be determined the way you did,
however in my case the filter had already been removed by the time I
got to it. Thus my problem.

Is what you used a polarizer from a direct view LCD ? If so I think
that explains the lower transmission, it probably has some anti-glare
or anti-reflective properties that are not needed in a PTV.

Problem is I think the new filter(s) are going to run hotter due to
those properties.

I think we will be able to repair these things if 1, we get them while
there is still some of the original filter to determine orientation
and 2, obtain the high transmission polarizers.

Oh, I forgot number three, have the hands and skills of a microsurgeon
and quit drinking coffee three days before working on them. For a
fraction of the pay I might add.

Mine is coming back when the work slows down. We can barely keep up
right now. Actually I am surprised I wasn't handsomely bribed to work
today, with super bowl Sunday coming tomorrow. But I have this policy
of not working Saturday anymore so, this would have to be one sweet
bribe, and I think they know it.

Anyway, if you have a lower light output than before, I think it will
burn up faster than the original. I don't think you can really call it
repaired. If it burns up in a few months, the customer will blame you,
not the manufacturer. I could say it right now, the filters should all
be glass, or embedded in glass, not glued on like a decal. In
addition, I believe the manufacturers know of this limitation.

Congrats on making progress on this, but that doesn't solve my
problem. I still have the burning question, is the light still
polarized at the lens output ? If so, with it running, when the blue
blacks disappear that is the orientation. With a bit of mental
gymnastics, looking at which way the mirrors go in the light engine, I
think I could make a heck of a good guess.

JURB