Optical Block Removal/Rebuilding

Audio/video connection area (chassis assembly) screws with arrows pointing at them:

Rear cover removed. From left to right, note (1) the audio/video connection unit (chassis assembly), (2) the center pillar (large metal plate in front of the optical block), (3) the main cooling fan, and (4) the woofer (speaker) block assembly.:

Center pillar removal

Disconnect the two ground wires from the connector on the center pillar (metal plate between the audio/video connection unit and the main cooling fan). Remove the five screws with arrows pointing to them from the center pillar. Note that the screw on the middle-right goes into the main cooling fan housing, which must be lined up properly when reinstalling. Also note that there is an optical block support guide on the back of the center pillar near the bottom (see the two screws in a small metal plate at bottom of the center pillar). This guide slides in a slot, requiring the center pillar to be lifted for removal. Once all of the screws are removed, it should be easy to gently lift the center pillar up then out from the bottom bracket. Set the center pillar aside with its screws so that you do not get them mixed up with others.

Center pillar (removed):

Side view of removed center pillar showing optical block support guide:

Main cooling fan removal

Remove one more screw at the bottom of the fan housing (in addition to the one that was removed with the center pillar). Note that it is not necessary to remove the fan itself from the housing. It will come out as an assembly.

Follow the wires (black, yellow, and red) from the fan to a connector. Pull the connector apart. It can only be re-inserted in one orientation, so you should not have to worry about that. Remove the fan wires and connector from the white wire holders (purse locks). Finally, slide the main fan and housing outwards toward the back of the TV:

Main cooling fan with housing (removed):

The following photo is of the back of the TV with the center pillar and main cooling fan/housing removed. Note the screw at the bottom middle of the photo. This is the second one that needs to be removed to release the fan housing. The optical block is the large unit between the audio/video connection unit on the left and the speaker on the right. The green electronics board attached to the back side of the optical block (with the red wires leading to the right and to the projection lamp area) is the power supply block (also known as the lamp drive unit or ballast). The black "sensor wire" should be removed from the clip by the fan on the top right of the optical block. It creates a loop as it goes through the white purse clips on top, through the clip, and then back across in front of the power supply block to its starting point (remember to re-create this loop during re-installation):

Audio/video connection unit (chassis assembly) removal

Remove the screw at the top of the metal support beam to the left of the audio/video connection unit, and remove the beam by slightly lifting the plastic TV case just above the beam. The audio/video connection unit is not secured to the TV. It can be slid out the back of the TV by lifting it up slightly and pulling. Make sure you do not put unnecessary stress on any of the many wires that go from the unit to other parts of the TV. For now, you only need to slide it out and slightly to the left to gain access to one of the screws securing the optical block to the TV:

Audio/video connection unit partially slid out:

Optical block (optics unit assembly) removal

There are two screws securing the optical block to the TV housing that are somewhat difficult to access and require a long-shafted Philips screwdriver. Note that in some other models, there apparently are three screws.

The leftmost screw securing the optical block (accessible after sliding out audio/video connection unit):

The rightmost screw securing the optical block to the TV (accessible through the semi-circular "slot"):

Remove all of the wire bundles from the white purse locks sticking out the top of the optical block, and slide the optical block out of the TV while also sliding the audio-video connection unit. Here is a photo of both units out of the TV:

The following photo shows the area of the TV to which the optical block was secured by the two screws. When re-installing the optical block, make sure the screws are secure. The alignment of the block will affect the alignment of the picture. If it is not tight up against the foam gasket on the TV housing, the picture may be crooked:

Wire disconnections

There are four additional wire connectors that should be disconnected to enable easy removal of the optical block. One connects the audio-video connection unit to the speaker (woofer) and is located on the speaker enclosure (see previous photo). The wire bundles for the remaining three connectors may be attached with tape to a fan housing on the top right side of the optical block. Remove the wire bundles from the tape, and disconnect the three connectors:

You should now be able to freely access the optical block for any of the subsequent procedures described below.

Optical block replacement

If you are sending your optical block in for rebuilding, the rebuilders will likely request that you leave all parts on the optical block for testing purposes, so you should only disconnect the remaining wiring that connects the optical block to other parts of the TV.

• • If you are doing a direct replacement of your optical block with a purchased part, the purchased part likely will not have a projection lamp or power supply block on it, so you will have to remove those parts from your current optical block and install them on the replacement.

Disconnecting wiring from power supply block

This step may be optional, if the power supply block must be transferred to a purchased replacement optical block. Undo the blue plastic-coated wire holders to release the two wire bundles. Disconnect the connectors shown with the dotted lines in the photo below. One, which presumably provides power, is disconnected directly from the power supply block, and the other is a regular wire connector.

Disconnecting the optical block fan wires

Disconnect the optical block fan wire connector:

Disconnecting the wiring from the optical block circuit board (C Board)

Carefully pull up on the three wire connectors directly connected to the top of the C Board:

Final wire disconnection from C Board

Remove the screw and gently pull the blue ribbon ribbon cable out of the side of the C Board:

Your optical block should now be entirely free of the TV and ready to ship. I recommend adding specific protection for the projection lens, then sealing the whole unit in a bag to prevent infiltration of dust or packing materials, then carefully packaging it with substantial padding.

Removing the projection lamp and power supply block (in cases where you are installing a purchased replacement optical block)

To remove the lamp and housing, loosen the hex screw attaching it to the optical block and pull the housing outward from the metal clips. To Detach the power supply block, remove the four screws attaching the board to the optical block and the two screws attaching the lamp connector.

Picture of replacement optical block and circuit box for KF-60WE610 (courtesy John Setar)

Here is a picture of a replacement optical block for the KF-60WE610. Note that the lamp and power supply block need to be removed from the old optical block and attached to the replacment.

The following two pictures show a circuit box that helps drive the optical block in at least some WE610 models (and perhaps others). It is attached to the audio/video connection unit and must also be replaced on some models. Otherwise, the color will not be correct (e.g., blue tint across entire screen).

Optical block cleaning

Cleaning alone is likely only effective under very limited circumstances (e.g., the pink/purple fingerprints/blotches thought to be caused by dust alone). If you intend to replace your optical block, skip this section and go to the Optical block replacement section.

Remove the black LCD panel cover to expose the area with the LCD panels:

Optical block with LCD panel cover removed:

Close-up of LCD panel area (note that the locations of the blue and red LCD panels are reversed in some models):

In theory, blowing air over the LCD panels and other internal parts could move some dust. In addition, the glass on the projection lens can be cleaned with lens paper and solution. Aerosol (canned) air is not recommended, as it can come out very cold and/or spray moisture, so extreme care should be exercised when using it (do this at your own risk). More thorough cleaning can be accomplished by further disassembling the optical, as described below.

Optical block disassembly

The method described below requires even more care and patience, particularly the points where the LCD ribbon cables and the light path filters are removed. However, it will allow much more thorough cleaning of the internal parts, as it enables direct access to the filters and LCD panels.

Note that Paul Patience has created another web site (Sony LCD Projection TV Cleaning Instructions) that describes this process on a KF-42WE620. It includes instructions and photos on accessing and cleaning the individual LCD panels, prism faces, and filters inside the optical block. Also note that, on the KF-42WE620 (and perhaps all 2003 Grand WEGA or "WE" models), the locations of the blue and red LCD panels are swapped relative to the KDF-55WF655 (and perhaps all 2004 Grand WEGA or "WF" models).

Remove the centrifugal lamp cooling fan. It is held by 3 silver-colored screws, as indicated in the photo below.

The following photo shows the centrifugal lamp cooling fan removed. Note the two silicone shock absorbers on which it was mounted. Next, remove the black plastic lamp fan mounting plate. It is held by 4 silver-colored screws, as indicated in the photo below (screws removed):

Remove the projection lamp by loosening the hex screw and pulling it out of the clips.

Next, remove the black plastic wedge-shaped piece that covers the circuit board on top of the optical block. It is held by 4 silver-colored screws, as indicated in the photo below:

The following photos show the optical block with the lamp fan, lamp fan mounting plate, LCD panel cover, wedge-shaped piece, and projection lamp removed (note the that the blue and red LCD panel positions are reversed on some models):

Next, the 3 copper-colored ribbon cables must be removed from the circuit board on top of the optical block. To accomplish this, carefully lift up one of the tiny beige-colored "handles" from one side. One way to do this is to place a small flat-head screwdriver underneath and gently lift up. The beige handles will raise about 45 degrees, and you will be able to gently remove the ribbon cable. In order to replace them properly later, note that the ribbon cables are inserted near the top of the handles, and that only a small amount of the gold-colored area is visible when fully inserted. See the photos below for more detail.

Lifting ribbon cable connector:

All three ribbon cable connectors loosened:

All three ribbon cables removed from their connectors:

Next, remove the portion of the optical block that contains the LCD panels, prism, and projection lens. It is held by four silver-colored and four black screws, as indicated in the photo below. Pull this unit off the rest of the optical block, while carefully monitoring the ribbon cables to make sure they do not get caught. Note that the clear dome on the projection lens appears to be made out of plastic.

Below are photos of the removed panel/prism/projection lens unit. Projection lens side (optical block fan filter removed--two silver screws):

LCD panel side:

The optical block fan filter is made out of a Scotch-Brite-like material and is stapled together through a piece of beige-colored adhesive tape. It seems a rather crude construction that is incapable of filtering small dust particles. This filter in my TV was not particularly dirty, nor was the centrifugal fan. I have seen others that are very clogged with dirt:

Photo of main optical block after removal of panel/prism/projection lens unit:

Close-up view of blue and green light path filters. The filter in the blue light path appears orange, and the filter in the green light path appears yellow:

Close-up view of filters in green and red light paths. The filter in the red light path appears blue:

Next, remove the circuit board with sheet-metal shielding from the top of the optical block. It is attached with 3 silver-colored screws located, as indicated in the photo below:

Next, remove the large black plastic plate that covers the remaining part of the optical block. It is attached with 6 silver-colored screws located, as indicated in the photo below. Prior to lifting off the plate, remove the red wire that winds through the posts on the plate. This is one of the two power wires (the top one) that goes from the power supply block to the projection lamp.

After removal of the black plastic plate, you can access the screws that secure the filters through which the light travels just prior to reaching the LCD panels. In addition, you can see the centrifugal fan that cools the internal LCD parts.

Parts to clean

Carefully clean both sides of the following parts, preferably with optical quality lens paper and cleaning solution:

• • The filters and adjacent lenses in each of the three light paths

  • The outside and inside surfaces of each of the LCD panels

  • Other exposed parts in the light path

The following photo is of the filter in blue light path, which has been removed for cleaning. Note the cloudy discoloration on the filter in the shape of a rectangle with an oval shape in the middle. This seems to be characteristic of the filters in the blue light path, likely arising from exposure to heat and light, particularly UV light. This phenomenon is likely a cause and/or effect of the blue discolorations:

The following photo shows the gaps between the LCD panels and the prism through which it is possible to clean the surfaces. DO NOT attempt to unscrew the LCD panels from the prism faces, or you will likely lose your convergence upon re-installation:

Pictures of disassembled optical block on KDF-55XS955 (courtesy of Bob Scott) -- similar to above

© Copyright 2009-2012 by Steven P. Linke. All rights reserved.