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I am answering my own thread. Because I did not receive any answer I decided to try to replace the burnt polarizer myself. And actually succeed.
Here is the procedure:
To take the upper white colored cover off the projector, you have to unscrew 6 screws and 5 additional screws that hold the side silver colored covers. All of these screws are on the bottom of the projector and they are all of same type (don't worry, just get them out).
When the screws are out, turn around the projector and take off the side silver covers (be careful: left cover has buttons on it, so it is connected to the projector with a flat cable).
Slightly pull up the projector upper cover and carefully disconnect its flat cable from the main circuit board. Now you can take off the cover.
Now you can also disconnect the flat cable of the left silver cover with buttons.
The projector is open. You have to take off the circuit board to get to the optic engine and the prism-lcd-block.
The following picture depicts the connectors you have to disconnect (red arrows) and the screws that have to be put out (blue arrows).
Be carefull with the connectors (especially with the three flat lcd connectors).
Now that the board is out, you can see the optic engine, which you also have to take out so you can take out the prism block.
The optic engine is held in place by only 4 screws (see the following picture).
First take out the lamp by undoing its two screws (blue arrows) and then undo the 4 screws (red arrows).
Now that you have the optic engine out, you can carefully turn it around and find one screw below the prism block. If you undo that one, the prism-lcd-block falls out (be careful not to let it fall down, because it can get damaged).
Here is the prism block with lcd displays on it:
When I looked through the prism block, I could see the burnt polarizer, which was unfortunately deep inside the block (just next to the prism).
But because I was very optimistic and I really wanted to have a good projector again I took a deep look at it and then decided to get the poor burnt thing out
You cannot get this piece of glass out by undoing screws, because it is glued into the assembly. But if you take the two plastic covers off, you can see how it is glued onto the prism block assembly at four spots (4 drops of black glue). All you can do now is to take a scalpel and cut this glue off so you can take the filter out. Be careful to remember how it was turned.
When I got mine out, it looked like this:
The damage is very obvious (it is very rough in the middle, and a circle can be seen around it - like a bubble).
This was the main cause for the distorted picture.
There are few peaces of glass in the block:
- The first is an "incidence" polarizing filter, but it is not mounted onto the prism block, but on the optic engine assembly.
- LCD screen (mounted with two screws)
- First unknown filter (mounted with two screws)
- Second unknown filter (mounted with a clip)
- "projection" polarizer (mounted with a glue and burnt in my case)
You dont have to disassemble any of them to remove the bottom "projection" polarizer, because it's not any easier to remove it if you remove the lcd and the following two glass filters. Surely enough I didn't know that so I removed all of them and then I had to allign the lcd screen...
I had an old non-working LCD monitor in a garage, so I took it apart and took out the LCD screen. Then I delaminated it (by that I mean pulling apart the two thin glasses that the LCD is made of). The outer panel of these two (the one that was at the outside of the LCD monitor) is just perfect for the job, because the glass is as thick as the glass of the burnt polarizer and it also has a polarizing filter already glued onto it. You just have to scratch off the black surface on the other side (these are very tiny red/green/blue filters for each pixel, but we dont need this surface).
You just have to cut out a peace of glass of the same dimensions as of the burnt polarizer. VERY IMPORTANT: the angle has to be correct. When you put the new and the old polarizer together and allign them, there should be no light blockage (all the light that goes through the first, should go through the second, and when one of them is turned for 90 degrees, almost no light should go through). This is very important, because otherwise some light will always get through and you will have slightly green screen instead of black.
Cutting the glass was a pain in the ass for me. These diamond glass cutters just didn't work for me. So in the end I decided to brake the big lcd screen glass in pieces and take a small, but big enough piece and grinded the square filter out of it. Prior to that I glued some tape on both surfaces so that the glassy dust wouldn't scratch it.
When you have a new polarizing filter glass cut out of the old LCD monitor, you can glue it into the place of the old one (I used a two component glue called "liquid metal", which won't get damaged by the heat). And one more thing: you have to clean the remains of the glue off the prism block assembly (the new filter has to lie perfectly flat, otherwise you will have a focus problem) (i.e.: left side of the screen will be in focus, while the right side will be slightly out).
Clear the oil and dirt from the polarizer before gluing... (you probably touched it with your fingers and left some oil on it)
Clear the glasses of the prism block (4 lcds and the "light outlet" glass) before mounting the block back into the optic engine. Mount everything back together...
LCD allignment (green):
As I said I removed the LCD screen so I had to alling it after replacing the polarizer. It is not too complicated... you just put the optic engine to the table and turn off all the lights in the room. You have to get a pocket torch (flashlight) (the brighter, the better) and direct it into place where the projectors lamp would be normally placed. On the wall there should be white image with some green and pink lines along the sides (in case the green lcd is misalligned). Set the focus of the projector so that these lines are sharp.
Now you just take the prism block out, unscrew the two lcd screws (I mean just a bit, don't take them out) and move the lcd to the direction where you saw a green line. For example: if the green line was at the top of the projected image, you should put the lcd up a bit (but REALLY just a bit!) Put the prism block back in and see if it makes and difference. Repeat the procedure as long as the image is not pure white (meaning there are no green or pink lines anywhere on the projected screen). The problem is that you have to find a method for making really small moves of the LCD - maybe tapping it with a screwdriver or something. With a bit of luck and some patience it can be done pretty well!
I had some doubt regarding my new cut-out filter as it is not made for high temperatures, but we will see... so far I watched like two or three movies with it and I can see no difference in picture (it is still clear and non-distorted). If this filter also gets burnt, I will probably order one from polarization.com:
This filter is high temperature resistant and should be ok for the job, but as for now it is not needed
I hope I gave you an idea.