Rear projection TV?
Sounds like coolant. It can get contaminated and then grows dark mold in the fluid, this then floats around in the coolant causing color impurity in the picture. Projection models I've delt with always had sealed coolant units integral to the tubes. I understand on some units the coolant can be replaced but it's generally not very sucessful. Not something you can do yourself.
However, first check for any 'customer adjustable' convergence settings in your instruction manual. You may find it's just the convergence settings are out, as this can also give color problems.
Cobweb
November 2004
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