Dust inside the lens on a mitsubishi projector

Most likely your DMD chip has dust or hair on it. You can try blowing it out with compressed air but the best thing is to tear down and clean the dmd chip itself. Very carefully. Here is a video of a similar unit. SO far all the DMD projectors I have worked on have had a very similar set up. Take pictures as you go.
MItsubishi XD206u DLP Projector Lens Assembly Cleaning

This is a dmd chip going bad. Here is the replacement on a very similar model. You would need to verify your chip number to be sure. Love to know if it is the same as the 250 and it probably is. http://youtu.be/775YOs-aOPc

Hello
It is actually a very skilled job. You have to disassemble the lens assemble as a whole to clean it. There is a special type of liquid, uses for camera lens claning. It can be bought from most of the camera selling showrooms. But, if you are intented to do this work by yoursef, you have all the small to very small type star and plus point screwdrivers, that watch repair persons have. Just see, this is not a simple jpob as you thinks. If you have skill, patience, and some knoledge about the internal fittings of the lens assembly, you can do it by yourself. OK.

1. Remove the air intake filters on your DLP projector. As explained by InFocus, a manufacturer of LCD and DLP projectors, each DLP model will house the air filters in a different location. However, for most DLP projector products, the filters are accessible by unclipping a simple plastic latch.

2. Wipe the air filters with a small cloth dipped in rubbing alcohol.

3. Blow compressed air into the unit's vents. This will force some internal dust out of the DLP projector, but you may still need to open up the unit for additional dust removal.

4. Unsnap the main cover from your DLP projector. Because DLP projectors need periodic lamp replacement, the main cover is rarely secured with screws or bolts. However, if the DLP projector's cover does not snap off, then you'll want to inspect the unit for possible screws or an alternate release latch.

5. Reach in and remove visible dust globs with a paper towel. Be careful to avoid touching the lens, as fingerprint smudges can diminish DLP projector image quality. If you accidentally smudge the lens while picking out dust blobs, wipe the lens with a dry, lint-free microfiber cloth.

6. Spray compressed air into your DLP projector to remove any lingering dust particles.

7. Close up the projector and reattach the filters.

This is a dlp projector and has a bad DMD chip. Most models are very similar. Here is a video of a similar repair.

Your projector needs little maintenance. The only thing you need to do on a regular basis is

to keep the lens clean.

Never remove any parts of the projector except the lamp. Contact your dealer if other parts

need replacing.

Cleaning the lens

Clean the lens whenever you notice dirt or dust on the surface.

• Use a canister of compressed air to remove dust.

• If there is dirt or smears, use lens-cleaning paper or moisten a soft cloth with lens cleaner

and gently wipe the lens surface.

Never rub the lens with abrasive materials.

Unplug you projector and allow the bulb to cool. Open the area where the projector bulb is located. Check the projector lens for any damage and clean it from dirt's and dust. Same as with the bulb.

Check for dust on the lens. There may also be dust inside the projector on the mirrors, lenses, or LCD. If cleaning the lens on the outside doesn't resolve your problem, I would contact a professional to get the insides cleaned out.

Good Luck!

canned air. if you take the lens assembly apart to try and clean it any other way, there's a slim chance you'll get it back together properly. plus, they thread lock it. it's usually air-tight, but if it isn't, used the canned air to blow the dust out. chances are, the dust is inside the projector itself and on the back side of the lens assembly.

I have an Optoma EzPro 737 DLP projector that accumulated dust inside the lens and for ages I couldn't figure out how to get rid of it. It cast shadows onto the picture and scattered light outside the edges of the picture. I thought I'd have to dismantle the whole lens assembly (then realised that this is virtually impossible without being an expert). I then stumbled upon a little black rubbery plastic panel on the side of the light path, which unclips. I then realised that the dust had built up on the lens that sits in front of the DMD chip (the thing that makes the picture).

Here's what I did, with the case open and having vaccuumed out all the dusty parts of the projector to avoid making the situation worse:
- Took off the little rubbery panel,
- Removed the lamp from the projector and placed a flashlight inside, shining into the light path (or a mirror directing light from a table lamp above)
- Looking directly into the lens from close up, you should be able to see the particles of dust stuck to the inner lens (with a nice magnified view)
- First tried blowing air into the gap on the side of the light path (I used a balloon pump).
- Next, I poked a piece of thick nylon fishing line into the hole so that it could touch the surface of the inner lens.
- While looking into the lens, I could see the tip of the nylon, then directed it to the largest dust particles and used it to scrape them off (nylon is much softer than glass, so won't scratch the lens).
- This was quite time consuming but I got rid of the most obvious bits.

I'm not sure how different this would be for another model of projector - but I hope it helps!