LCD Projector screen display - blue screen

Hello Anonymous,

A DMD is a chip with thousands of tiny mirrors that change angles in order to block or let light through, creating the image you are viewing. Texas Instruments has a great video and explanation here: DLP MEMS

The spots could definitely be caused by a malfunctioning DMD. As much as we would like your business, you will be better off purchasing a new projector. You can try searching ebay for a used working version of the projector so you can utilize the hours on that new lamp (there is currently one for sale for $125 on ebay). If you want to get a new projector, I recommend a website called Projector Central (Projectors Projector Reviews LCD Projectors Home Theater DLP Projectors...) for research on finding the right match for your needs.

In the future, if you have any repair or lamp needs, Mentronix repairs and stocks lamps for over 30 brands of projectors.
Mendtronix Inc AV Services LCD DLP Projector Repair Multimedia...

this discoloration is the begining of the lcd panel being thermal damaged. this happens when the projector is being used for a long period of time and then being shut off using the switch on the rear of the projector instead of the on/off on top or the remote. to fix it it will have to be replaced. very expensive major repair.

if these blemishes look like maybe its fuzz or something, you can remove the top cover and use compressed or canned air to blow out the area where you see 3 orange flat cables going under the main board into the lcd panels. blow it out good and be careful not to disconnect the cables as that can be a pain for the inexperienced. If this doesn't fix your problem, then I would say that the lcd panels have been burnt due to shutting the projector down improperly numerous times and no it is not worth repairing unless you get a known good light engine for less than the cost of a new projector plus labor-- unless you DYS.

This projector is one I've worked on many times and you are correct. The lcd panels are burnt probably due to a hard shutdown not allowing the fans to cool the inner components done repeatedly over several sessions.

if it's a pixelated line, it's your lcd panel. if it's a blended, uneven line, it may the polarizer on the lcd panel. either way, you'll have to replace the whole optical engine.

the light filter on one of the lcd panels is burnt due to excessive heat and dust. unless you find a scrap machine to get parts from, you're out of luck. they don't sell individual parts for the optical engine.

either the light filter behind the blue lcd panel or the fly-eye lens (both inside the optical engine) have developed a burn spot from overheating. infocus doesn't sell individual parts for the optical engine, and the whole thing must be replaced. but unfortunately, it's the most expensive part of the projector, usually upwards of $2000 (and there's none in stock).

first of all, the infocus lp 790 is an lcd projector, not a dlp. second, the light filter in front of one of the lcd panels is burnt, and unfortunately cannot be purchased separately.

Using Windows Mobility center, Enable the Output to LCD Projecters.

the red is cutting out. white=blue+green+red. without red, you get blu+green, or cyan. if this was an lcd projector, i'd say it's a burnt light filter, the red lcd, or the lcd has come unplugged. but since this is a dlp projector, you have either a dmd board issue or a main board issue. either way, it'll be pricey.