Subject: Re: Fiber Optic Backlights? (was Re: electrolumenescense)

From: [email-masked] (Loren Wilton)
Date: 27 Jul 1995 08:43:53 GMT

In article <[email-masked]>, [email-masked] (Lord Jonin) wrote:
>Loren Wilton ([email-masked]) blurted:
>
>: (although fiber optic backlights are perhaps more common on LCD panels).
>
>This may be something I am looking for.  Where might I find these type of
>products?
>
>I am bascially looking for backlighting techniques to flood a 1 1/2" circular
>display - and other sizes later.  I havent worked with fiber optics, but I
>
>p.s. most my projects are made for special effects/props.  That is why some
>of them have to be very small, and others have to be very visible. 
>Not knowing the lightsource of the Fiber optic backlight, I though it might
>be cool to attach one/several of the new RGB LEDS to it so I can vary its
>color on the fly.  This might not be feasable depending on how the actual
>light source is rigged on those things.

Again, I don't have references handy, although the same electronics trade
journals will have lots of ads in them for backlights of various kinds.

The basic fiber-optic panel backlight is very similar to what you describe.
It starts with from one to 3 bundles of clear fibers, that are then spread
out to produce a flat layer of fibers.  This is sandwitched between a piece
of clear plex on the front and a piece of something else (probably reflective)
on the back.  You put lightbulbs near the ends of the fiber bundles, and the
result is an evenly distributed light over the panel area.  You put bright,
typically incandescent hallogen lamps at the bundle ends to illuminate the
panel.

A variation is a panel with all of the fibers terminated along the edge.
This kind is illuminated with a linear liight source, typically a flourescent
tube perhaps 4mm in diameter and 2, 4, 6, 9, or so inches long.

If you are doing this backlight as part of a costume, I recommend *against*
using electrolumenscent panel material, even though it is usually flexable.
Disney did this for one of their parades, and had problems with wire abraision
resulting in ocasional shocks to the actors, since this stuff runs on about
130V AC from an inverter.  They went to some form of fiber optic panel that
could be illuminated at a lower voltage.

I don't have any exact references on this, but you could try contacting
Walt Disney World Entertainment Division in Florida and see if you can
find someone willing to talk about their solution.

	Loren