Overhead projector TV: Need alternative backlight source..

[JonathanAnon]

Hi there,

I've made an overhead TV projector with an LCD screen and an overhead projector... similar to this video..

https://www.youtube.com/watch?v=b7lWqKHpGuc



But I am having a problem that the head from the overhead projector kills the TCP joining the panel to the t-con board... The guy in the video has a 230VAC fan that he pins to the side of the overhead projector.. But even with this I find that the heat kills it...

I was gonna use one of these. It's the same lumens as the overhead projector but runs coler..



I was thinking about taking off the magnifying element from the overhead projector, fixing it to the LED panel and then lying the lcd panel from the TV across the LED lighting panel...

Is there any reason why this would not work?

thanks,

[tom66]

Re: Overhead projector TV: Need alternative backlight source..

I do have to ask why you are doing this?

Such a projector will have terrible washed out contrast ratio and colour. It will also be difficult to avoid the screen door effect. If the TCPs do not die it will be the panel glass itself, if it gets too hot the LC will change properties causing colour distortion.

If you are building your own projector, why not try using a DLP engine out of a discarded rear projection TV - that will at least achieve a decent contrast ratio and brightness, with accurate colour, whilst not dying on you.

[JonathanAnon]

Re: Overhead projector TV: Need alternative backlight source..

Hi Tom, nice to speak with you again..

Yeah I know what you're saying.. I've thought about it myself, thinking "why bother just get a big TV" and I have a big 47 inch ambilight that I bought and fixed and another 42 inch as a spare.... But it's just something that was given to me to look at and I thought I'd try and push the concept as far as I could...

Also, I find with even a cheap LCD 17 inch screen on the overhead projector, and accounting for screen door / poor contrast / poor definition, it actually looks really good!... That is why I'm persisting with the idea... AND I have quite a few TVs and monitors with no backlighting, so I'd like to make use of them...