This project details how to make a diffused light display out of electroluminescent, or "EL", panels and an old cathode ray tube television.
For this project I wanted to recreate the glow of a television without the dynamic and distracting snow. To do this I hollowed out the internals of an old CRT tv, and added my own light source using electroluminescent panels. Electroluminescent panels work in the same way that electroluminescent wire, or EL wire works in that they glow when a current is applied to their phosphor coating. Electroluminescent panels are often used as backlights for displays, and because I had some of these lying around, as well as their drivers, I used a few of each for this project. The electroluminescent panels were ideal for this application because they emit a diffused light rather than a point light source like LEDs (a spotlight pointed at you isn't the most relaxing thing).
This instructable will focus on the basics of the project as each electroluminescent panel will have it's own specifications and needs.
WARNING: I am not responsible for any injuries incurred during the making of this project, proceed at your own risk.
Step 1: Choosing the TV.
For this project you need a cathode ray tube TV, or CRT TV. CRT TVs are old/heavy TVs with a big ?booty? sticking out in the back. I suggest you pick one that has nice case and one with a screen size similar to your EL panel if possible (although I had to use multiple EL panels to fit across my screen, more on that later).
Step 2: Opening the TV.
CAUTION!!! Opening a CRT is very dangerous as high voltage can be stored in the tube or capacitors. There is really no way of going about it that doesn't assume some level of risk, but reading the following links will give you a decent guideline of what to do/be careful of. I am NOT responsible for any injuries you receive. If you are not sure of what you are doing, DON'T DO IT.
Open up the TV and remove any circuits that do not hold the front panel together. Disconnect and remove the tube and place in a small bag or box.
Step 3: Hammer Time
This step gets a little messy, so its probably best to do outside while wearing safety glasses, protective gloves, and a respiratory mask (these old TVs can contain some nasty particles). First you will want to release the vacuum on the CRT tube. BE CAREFUL, releasing the vacuum can cause the CRT to implode. Some way to insulate the tube in the event of implosion (such as some padding or a box) or a way to distance/protect yourself is advisable. The easiest way is to remove the nipple on the stem of the tube, or if there isn't one lightly tap a screwdriver into the stem of the tube. A light hissing noise will let you know you have released the vacuum.
Next you will want to remove a lot of glass from the stem side of the tube. As you can see in a few of the photos the front glass has a metal clip at each corner (where the front glass was mounted to the panel). You want to leave the front glass, and mounting clips in tact obviously. You will see a joint about an inch up from the clips where the back tube is joined to the front glass. Ideally you would like to smash all the back glass off to the joint so that you would have a clean front glass with no jagged edges, but RESIST the urge to break the glass all the way down to this point, as you will often end up with a cracked front glass and a wasted CRT.
Once you have removed most of the back glass, STOP. If you have some jagged edges you can sand them down at this point. Inside the tube you will see a metal screen, remove and discard this if it has not come out already.
Step 4: Remount the front glass.
Take the front glass and remount it in the case.
Step 5: Driving the EL Panels.
I am not going to get into the specifics of this because there are too many variations and I only did it this way because these are the components I had on hand. My recommendation is that you buy a power supply paired for your specific EL panel, but if you are dead set on going DIY the whole way you could design your own driver.
Here I am using a large power supply similar to those found in a desktop PC to feed three separate EL driver boards that came with the EL Panels (one for each of the three panels I am driving). At first I tried using only one EL driver but the brightness suffered, so I tied three drivers into the large supply. Ideally I would have liked to have one large EL panel that fits my TV's screen perfectly, but I didn't get THAT lucky, so I had to use three EL Panels taped together. Taping the three panels together didn't look so good, so I had to make some adjustments (see the next step).
Step 6: Finishing touches.
Okay, so like I said before unfortunately I didn't have an EL panel large enough for my screen size so I had to tape three together. Although the three EL panels gave off a nice diffused light when taped together I could see the seem between the panels through the front glass. To fix this I cut tracing paper and put it in the front glass before placing my EL panels along the back. This made the light even softer and more diffused and also got rid of the visible edges between each panel.
Step 7: Donezo
After screwing the case back together the project is done. Check out the video to see it in action.
Thanks for looking.