How to create carved illuminated plexiglas with Cycles?

Hi! I’ve been trying to make images of carved illuminated plexiglas - it turned out very difficult.

How it looks in real life:

[ATTACH=CONFIG]358769[/ATTACH] [ATTACH=CONFIG]358770[/ATTACH]

I create an extrded plane for the plexiglas sheet.
I add a beveled curve to create a shape of the carve. I convert the curve to mesh and use it in a boolean modifier to substract the curve from the plane.
Next I add a light source - I duplicate a top or bottom edge face of the extruded plane. I move it away a tiny amount, so it doesn’t overlap with the original face, and I apply an emisson shader to it.

I also tried using an array of tiny emiting cubes to imitate a LED-tape. I’ve got an impression that Cycles ignores so small objects.

As for materials - I used glass shader for the plexiglas. I used one clean with 0 roughness, and another for the carves with roughness up so it diffuses the light more. I also tried combining the glass shader with glossy and translucent for more light.

I always seem to get not enough illumination on the carve. like I have not enough light, even when I turn the emision shader up to 10000000
It doesn’t seem to make any difference in the renders, but it does in the material preview in the properties tab.

Have you done such stuff? Would you share any tips how to set up materials and meshes?

pics link are dead!

upload pics here in forum
and show nodes set up

happy cl

Here’s my try…
The object is basically a glass shader, but the outer rim polygons have an emission shader with a “twist”: To the outside it’s just glass, but to the inside it emits light.


Takes some time to clear up (that’s 2500 samples) and doesn’t look entirely convincing, I’m afraid.
Turning off “Refractive Caustics” will spare you much noise you’ll otherwise see in surrounding surfaces and speeds up the render, too. Filter glossy seems to help as well (in this render it was set to 1.0).

I used an approach similar to the above to model a fibre optic.