Edge lighting acrylic, or very slim backlighting?

[Doyle]

I need to backlight (or edge-light?)a small piece of acrylic that gets mounted inside a vending machine in an existing opening/bezel. The area is approximately 4" x 6" and I can tap in to the existing power supply inside the machine (12v or 24v AC available). I am looking for the most economical way to do this because this client may hire me to do the same thing on dozens of other machines. How does one edge-light a piece of acrylic? Also, I stumbled on electroluminescent panel technology (paper-thin light panels) in my research and wonder if this might work?

Can anyone point me in the right direction to learn more about this? Any recommendations of what vendor to call to find the right components to build something like this?

 

[Techman]

You have several choices. Contact Wensco and purchase 3 light per module high intensity modules for about $2 each. These are about .400 thick about 2 inches long and about 3/4 in wide. Find a used 12 volt output wall wart and wire it up. Done!

OR get very low cost and...
goto ebay and purchase a roll of your color of choice LED lights for about 5 bux.
Purchase a UL approved wall wall wart 12 transformer.
Wire up the LED's observing the polarity. The roll of LED's has a 3M sticky back tape installed.
Line up the LED emitters along the edge of your panel. Done!

Shown is a back lit display using edge lit 1/8 plex panel 12 inches wide x 18 high.
15 LED emitters (about $1.00 worth) with a 12 volt wall wart (1.99 on sale from MPJA) wired up using 5.5x2.1 mm connectors (10 for $3 ebay)

Shown below is the very low cost method using edge lit technique. The art is very lightly etched into the face using a drag point on a CNC. IT is all but invisible when not lit. However it POPS when lit and is especially noticeable in low light conditions. Very nice.
Be sure to understand about forward voltages and calculate the resistors needed for very long life. I used no resistors on the ebay modules because the forward voltage is so low and they emit no heat.

 

[Doyle]

Thanks for your help! Is the wall wort necessary if we are able to tie into an existing power supply? Customer will be wiring it into the unit and not myself.

 

[Techman]

just need 12 vdc.. and in some cases need a resistor to reduce the voltage to the proper forward voltage.

 

[Doyle]

So, would these LED's be attached directly to the back of the acrylic with the graphics? Or are you saying that these would be attached around the edge/perimeter of the piece? I kind of figured that there would need to be some space to diffuse the light if they were placed directly behind the graphics, but I have no idea how much space or what kind of diffuser would be needed to avoid hot spots.

 

[Techman]

well,, I have no experience with what you are doing. However I would think a back lit would be better for a see through image. And then I would guess you need some space of about 3 inches. These LED's are bright. I would test using a thin white sheet of white opaque plastic to act as a diffuser.