It's as simple as taking part A and part B and rubbing them together to get the desired result !

I came up with this idea a while ago when playing around with some 5mm RGB Leds and the clear acrylic package (at least I think is't Acrylic) just wouldn't let my spectacular color mixing skills shine through.

Actually it was the total abundance of shining through and very little light diffusion that was the problem because these 5mm RGB leds have a rounded top that focuses most of the light in a 15 degree viewing angle when viewed from the top as apposed to from the side. (Staring directly into the beam of even these little 5mm high brightness leds even briefly is uncomfortable and can be harmful to your eyes!)

Diffused light from an RGB led gives a much more even and appreciated effect and won't be so hard on your eyes after hours of staring into the mesmerizing semiconductor hues.

The light from the diode needs to be scattered more and focused less. So we need an uncomplicated way to make tiny little evenly distributed scratches on the polished acrylic surface of the leds to help scatter the light more randomly, but like evenly randomly, ok?

Step 1: You Will Need :

Some fine grit sanding parer. A smaller piece of abour 2 x 5 cm handles better and I found that Silicone Carbide 600 grit Waterpaper works best but anything between 500 - 800 grit should work well although the result between grits may differ (You will not be needing any water with the Waterpaper for this application tough)

A scissor maybe to cut the waterpaper with, but I just fold it over and crease the fold a few times and it just snaps of easily

The doomed clear leds that are to be condemned to diffusion

your hands and skill as a craftsman

and very very importantly, an assistant*

*always have someone in the lab to blame if anything goes wrong

Step 2: Rubbing Part a and Part B Together

This step is self explanatory.

Hold the led by the pins right under the base for a firm and controlled grip.

You will find that you do not need to use a lot of force to get the effect started. Try to bend the sanding paper a little as you go around the led's side and sand as evenly as possible.

Wrap the paper around the led and pinch it a little while twisting the led around 3 or 4 times by the pins.

For the round top I place the sanding paper on a flat surface and with a swirling motion drag the led across it, without pressing down much on the led.