My Epson TW1000 projector recently
First, try using other cables you are using from the source, for example, if you are using a laptop or PC and you are using VGA cable, try using another one. This also applies to any other cable such as S-video, or the simple Video In RCA cable.
You may also want to check the plugs or the port connector, specially with the VGA or D-Sub on some models, look for obstruction or bent pins. Loose or obstructed or even corroded terminals and ports contribute to such "streaks" or even worse poor image quality.
Another thing to consider, specially if you are using a PC or Laptop, is to check the setting on the OS,(Graphics Properties). Be sure to set it according to, or as stated, or required resolution depth.
Lastly, if the lines you are referring seems to grow, or multiply as the projector heats up.Or, the lines seems to be "rolling" or "moving"- try one of these simple steps;
-- try other cables
-- try locating the "SOURCE" away from the projector, put them separated, away from each other
-- if you are using HDMI cable try using a new one
-- if you have plugged in the projectors power cord "along" with other electronics, in the same SOCKET, or extension, consider re-locating on of them, if possible, let the projector have it on "solo"
-- if your projector's Power Plug being a three prong, try plugging it in a three prong socket, or you can buy a 3-to-2 plug adapter
If none of those mentioned steps the following could be a possible fault;
-- LENS or the projector
-- the board or its components, IC'S etc
wherein any of them could be costly, firstly, the availability of parts, specially that being a digital equipment,thus, its quite hard to pinpoint the "real" fault, without actually trying to test with instrument or another replacement part.
But as for my experience on our ACER projector, the Plug relocation just did the trick, somewhat an interference caused by the grounding (improper).And making the projector "solo" on an extension or wall socket.
Hope this helps.
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