Broken LCD TV turned into a light table


[Steve DiRaddo] sent us this sweet little mod. After obtaining a free LCD TV that had a cracked screen, [steve] immediately tore it open to re purpose it. The end result was a computer controlled light table with audio. From what he says, it is very very bright due to the fact that it has 16 CFL tubes behind it as opposed to the usual 2 inside a PC monitor. The TV had a bult in RS232 command port. Whith some quick hacking, he was able to control power, channel, input, and volume via his laptop.

23 thoughts on “Broken LCD TV turned into a light table

  1. “I’d like to be able to feed several audio inputs into the thing and be able to select which one I want. Too bad for me, if there isnt a legit video signal entering that input, it ignores it completely. The TV will only switch to an input with an active video signal. A quick and dirty way to fix this is to take a single composite cable and plug one end into ‘Monitor Out’, and the other into the video input of your choice. This is called video feedback. It works though. If the screen was still working we’d see some really weird shit. Luckily, we aren’t exactly going to be needing good video for our purpose.”

    You can also just solder a 75ohm resistor across an RCA plug to make a terminator, and plug it into the video input. This did the trick on my TV.

  2. I have a traditional light table and I use it all the time. I still do a lot of analog art (not photography) and it’s always useful. If nothing else, it’s really cool to have a nice piece of glass to cut things on. Mine has two layers – one of frosted plexiglass, and a top layer of tempered glass. I’ve also used mine for photo-exposing silk screens. Controlling the exposure time with a computer would be super cool.

  3. This is not very effective for serious transparency (slide) review. Real light tables produce actual white light. Use a loupe to look at the “white” screen on the monitor and you will see the readily apparent components of the additive (RGB) color system rather than the white you expected.

  4. I’ve just tried this with a broken LCD. After LCD screen removal, the remaining light panel is very interesting: portable lighting system for photography/video, or may be flat light on the wall or ceiling…

    On mine, there’s a light diffusing plastic sheet on top of lighting panel, but once LCD panel removed, nothing keeps it in place anymore. So i’ve tried to dismantle the LCD panel itself hoping i could reuse the plastic screen.

    On one side, there was an adhesive sheet of dark plastic, and just under the broken glass. Once removed, the remaining part cleaned of the liquid cristal, i’ve realized it is in reality a polarising filter and could be usefull also! But in the other hand, it is a little dark, so it reduces the amount of light going through. I think i could remove another adhesive sheet of plastic on the other side but i prefer to keep the polarising filter as is.

    After this process, i was wondering if liquid cristal could be toxic. I should have think about this before dismantling the LCD glass panel :-< Does anybody know?

  5. There is no evidence at all that liquid crystals pose a health risk for humans, but tests are ongoing. At this point in time the teeny bits of glass that shred off at the edge of a cracked screen are far more dangerous.

  6. Maybe I missed it, but what brand of LCD TV is this?

    How did you find out the RS-232 command set?

    Are there RS-232 commands for controlling the brightness?

  7. Just a word of caution. While taking apart an lcd monitor, I realized that I opened the florescent light part of the monitor and probably exposed myself to the mercury.

  8. I believed this was a really fascinating post and I am really glad that wrote on this subject matter, there are not too several other weblogs that take this perspective

  9. My work donated a busted screen 32″ Apex Digital HDTV to me, but needed to keep the working power supply board and controller board for other projects. With just the inverter board and screen, is it possible to supply power enough for the backlight to craft into a light table?

  10. hey all good itea amd im using a lcd monitor as a light table the only thing is i have to keep it plugged in to my computer and extend desktop to keep backlight on.
    the lcd is broken and only backlight works.

    i would like to figure out what to do to keep backlight on, i’m an electronics amateur, i know a little but dont want anything to involved.

    have tried resistors across vga imputs, looked up pinout and other sites but cant seem to figure out how to keep it on short of plugging into computer and making active monitor.

    HELP PLEASE
    Dan

  11. @ daniel w That’s exactly what I am trying to do as well and usually end up getting to about ***HERE*** using various avenues of research. No one has been able to help me power up an LCD from a laptop without using the accompanying computer.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s