How to illuminate 40 sq ft of surface

[Wüstling]

For my little art car project I need to illuminate about 4 sq meters (43 sq ft) in bright red, yellow and blue.

It's on the outside surface of my vehicle, so I cannot just use a painted surface and point some lights on it to reflect the light.

Instead I need to have the surface glow by itself (e.g. using something like EL-Wire) or from behind (using a semi-transparent surface).

Due to the large surface, EL technology is very expensive (several $1000). I'd rather expected to spend no more than a $1k on it.

The other challenge is that it's not a flat surface, but curved in both directions. Imagine I want to make a sphere and light that up in the primary colors. That rules out plexiglass as that can hardly be bent/molded over a sphere, right?

The surface material doesn't need to be sturdy, i.e. it doesn't have to carry extra weight. So I thought of Polycarbonate. I could then illuminate it from the back with LEDs or other small lamps.

Has anyone got any pointers where I can get such plastics molded, and maybe also tinted with colors? So far I only found companies that do this only in large volumes as making the mold is expensive. I, however, don't need a high-quality mold, it just has to come close to "round".

The surface I need is actually for a UFO frame, 3.5m (11-12ft) in diameter, so I need something more closely resembling a donut, though only the outer upper part of it.

[Gazmatron]

Check out the 'Love Potion Amphora' art car. Those guys did an awesome job with 'Rowlux' and LEDs.