I have been given an LCD projector (Philips LC4441 with about 30 hours of usage only) that has a defective filter which makes the picture unwatchable (big area with yellowish to blueish wrong colours).
I have opened it and seen (from above) that the blue filter is distorted, maybe by heat (as opposed to the green and red filters which seem completely flat).
Does anyone know how to replace a filter on this model without damaging the light unit and where to find the filter ?
Thanks in advance.
Sorry, I wrongly posted the same question on a Panasonic thread
I have opened it and seen (from above) that the blue filter is distorted, maybe by heat (as opposed to the green and red filters which seem completely flat).
Does anyone know how to replace a filter on this model without damaging the light unit and where to find the filter ?
Thanks in advance.
Sorry, I wrongly posted the same question on a Panasonic thread
There are dichroic glass filters on ebay from time to time. They are mostly scientific surplus, so matching the specs will probably be hard ( assuming you can even detrermine the specs of the original ). Your best bet is probably to try to get another projector of the same model ( maybe a broken one or one w/ burned out bulb ) and just swap the blue filter or even the whole filter assembly if its easier.
filter replacement on LC4441
In fact I am a newbie to the subject of video projectors, and I have just realised by seeing an exploded view of a tri-LCD projector that the damaged filter is not the blue filter (I mean the filter which lets the blue light pass, which is done by means of a dichroic mirror) but the final (polarizing) filter placed just before the "blue" LCD.
Do you know if the polarizing filters in front of the LCDs are identical for red, green and blue (they seem to have the same orange colour)?
What is the exact purpose of this filter (is it UV or IR filtering ?).
Anyway, I still have to figure out how to unmount the filter...
Thanks in advance.
Thanks overdose.Overd0se said:
In fact I am a newbie to the subject of video projectors, and I have just realised by seeing an exploded view of a tri-LCD projector that the damaged filter is not the blue filter (I mean the filter which lets the blue light pass, which is done by means of a dichroic mirror) but the final (polarizing) filter placed just before the "blue" LCD.
Do you know if the polarizing filters in front of the LCDs are identical for red, green and blue (they seem to have the same orange colour)?
What is the exact purpose of this filter (is it UV or IR filtering ?).
Anyway, I still have to figure out how to unmount the filter...
Thanks in advance.
Let me know if you can't fix it. i am interested in buying one of these commericials with burn polarizers. To see if I can retro fit something. Thanks
After having left the projector for months in a box, i have finally decider to work again on it and I have succeded in founding how to access and remove the filter. Finally not very difficult just by removing the cover of the light box (fixed by only 8 screws or so).
It was then very easy to remove the filter, the problem now is to find a replacement one that will work properly and protect the blue LCD from the heat.
The filter is placed just before the blue LCD and just behind a lens, and it has a colour between rose and orange.
A very significantant part of the area of the filter (about 15%) has been visibly exposed to excessive heat and forms a kind of bubble, and that is the cause of the very important discoloration observed.
The two other filters and the LCD panels (including the blue) do not seem to have suffered at all.
Any suggestion where to find this filter (dimension 31 x 24 mm).
Thanks in advance.
It was then very easy to remove the filter, the problem now is to find a replacement one that will work properly and protect the blue LCD from the heat.
The filter is placed just before the blue LCD and just behind a lens, and it has a colour between rose and orange.
A very significantant part of the area of the filter (about 15%) has been visibly exposed to excessive heat and forms a kind of bubble, and that is the cause of the very important discoloration observed.
The two other filters and the LCD panels (including the blue) do not seem to have suffered at all.
Any suggestion where to find this filter (dimension 31 x 24 mm).
Thanks in advance.
photograph of the LC441 blue filter
Here is a photograph of the damaged filter:
Here is a photograph of the damaged filter:
An externally hosted image should be here but it was not working when we last tested it.
- Status
- Not open for further replies.