This is a common problem with a micro-display projection TV set. Its because of dirt or something else is on the display screen and needs to be cleaned off. Most LCD projectors have shields and casing around the display and light box part of the set and should not be taken apart without a service manual to help you take out the proper seqence of screws. if and once you do get into the display, never spray anything directly onto the microdisplay and never use a paper produt to use to wipe it. You should always follow the directions to clean in the service manual. Let us know if you had to get a pro to assist you and how you made out and good luck.
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