not sure if'm describing this corretly. However i have an old samsung DLP which i have put blood sweat and tears into over the past 3 years
replaced the dmd board (twice due to first one being faulty)
just recently (2 months ago) replaced the bulb with a philips brand.
am now seeing random purplish "static" in various areas on the screen.
Mostly when playing xbox on component in areas which should be white
I am thinking its the color wheel. I had the brightness set pretty high
(at request of wife) turned it down and the purple static is gone