ChuckMountain
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There are a lot of threads on the net about issues with a variety of JVC D-ILA projectors having coloured stripes at the edge of the screen appear over time. There are a variety of reasons given and some fixes suggested but in this thread I will show what I found on a repair of an X35. (It's not for the faint hearted)
Thanks to @Cocksure for donating his projector to this worthy cause
Depending on the orientation of the projector these typically appear at the right hand side for ceiling mount or left if shelf mounted. In this case, mine is shelf mounted and has a magenta/purple/pink stripe down the left had side, most visible on a white background.
The cause in this case is a misalignment of the yellow mirror in the optical pathway. There are some suggestions on the web.
The main optical block removed
Below are the mirrors and their adjusters, the three metal plates with two black screws.
The mirrors some of which are dichroic are locked in place by two pieces of metal which are glued together to prevent further movement. There is marginal adjustment allowed because of the black pegs, not enough to cure it. Removing the pegs might allow a bit more movement but the screw holes are round and so only allow a tiny amount of movement.
Blue Mirror is Top right hand, yellow mirror is bottom right, Red\orange ? is bottom left.
The way to fix it is to break the glue bonding the two metal pieces, adjust and reglue. The problem is that to do the adjustment you need to do in place\powered up with the various cooling in place. Only the top blue mirror is easily adjustable, the yellow one is harder but not impossible. The red one is behind a circuit board. What I imagine in the factory is that the optical block is calibrated in an adjustable harness the mirror adjustment is set then glued to prevent further movement.
The mirrors particularly the red one are very thin and though I didn't break them I think it would be easy to do.
A fraction of a millimetre movement is enough to resolve the problem in some cases. I then reglued using No Nails as its removable and I had it to hand.
A few comments on other cures on the web:-
1) Glue - failure - not convinced about this, the glue was certainly intact on both mirrors adjusters and there was no obvious movement. Expansion and movement over time of parts could cause the issue
2) Blowing hot air into it - you would have to pretty lucky to have this cure it
3) Aluminium tape - this will work but effectively you are substituting the tape for the glue and using friction to hold the mirror adjuster in place. With no glue the adjuster moves "freely". This may cause excess pressure on the mirror.
When you remove the adjuster, by taking off the black screws you may well pull the mirror out of the other side holder as well. These are delicate.
The projector has done quite a few hours (~4,000??) and has collected a lot of dust, at the same time I stripped down what I could of PJ and the optical block and cleaned it.
Before I started (rather dusty )
Was it a good idea taking it all to bits
The optical block exposed - delicate mirrors, dusty
Dusty mirror
Optical block after cleaning
What happens if you break the blue mirror glue
Fully cured (though convinced there might be a yellow tinge at the top right)
Although there is different exposure in the last 2 pictures, the PJ is significantly brighter than it was when I first got it.
Thanks to @Cocksure for donating his projector to this worthy cause
Depending on the orientation of the projector these typically appear at the right hand side for ceiling mount or left if shelf mounted. In this case, mine is shelf mounted and has a magenta/purple/pink stripe down the left had side, most visible on a white background.
The cause in this case is a misalignment of the yellow mirror in the optical pathway. There are some suggestions on the web.
The main optical block removed
Below are the mirrors and their adjusters, the three metal plates with two black screws.
The mirrors some of which are dichroic are locked in place by two pieces of metal which are glued together to prevent further movement. There is marginal adjustment allowed because of the black pegs, not enough to cure it. Removing the pegs might allow a bit more movement but the screw holes are round and so only allow a tiny amount of movement.
Blue Mirror is Top right hand, yellow mirror is bottom right, Red\orange ? is bottom left.
The way to fix it is to break the glue bonding the two metal pieces, adjust and reglue. The problem is that to do the adjustment you need to do in place\powered up with the various cooling in place. Only the top blue mirror is easily adjustable, the yellow one is harder but not impossible. The red one is behind a circuit board. What I imagine in the factory is that the optical block is calibrated in an adjustable harness the mirror adjustment is set then glued to prevent further movement.
The mirrors particularly the red one are very thin and though I didn't break them I think it would be easy to do.
A fraction of a millimetre movement is enough to resolve the problem in some cases. I then reglued using No Nails as its removable and I had it to hand.
A few comments on other cures on the web:-
1) Glue - failure - not convinced about this, the glue was certainly intact on both mirrors adjusters and there was no obvious movement. Expansion and movement over time of parts could cause the issue
2) Blowing hot air into it - you would have to pretty lucky to have this cure it
3) Aluminium tape - this will work but effectively you are substituting the tape for the glue and using friction to hold the mirror adjuster in place. With no glue the adjuster moves "freely". This may cause excess pressure on the mirror.
When you remove the adjuster, by taking off the black screws you may well pull the mirror out of the other side holder as well. These are delicate.
The projector has done quite a few hours (~4,000??) and has collected a lot of dust, at the same time I stripped down what I could of PJ and the optical block and cleaned it.
Before I started (rather dusty )
Was it a good idea taking it all to bits
The optical block exposed - delicate mirrors, dusty
Dusty mirror
Optical block after cleaning
What happens if you break the blue mirror glue
Fully cured (though convinced there might be a yellow tinge at the top right)
Although there is different exposure in the last 2 pictures, the PJ is significantly brighter than it was when I first got it.