The concept of using edge lighting in transparent materials has been known for many years. The light travels through the distance of the medium, whether it is a clear polymer or glass, by way of internal reflection. The light goes from edge to edge and escapes at the far edges with the effect of no light being lost. This is true of glass fiber as well and is the basis of fiber optics.
But an interesting twist happens when the surface between the edges is disrupted by a surface scratch or in the case of glass, when the surface is etched. Some of the light exits at the disruption and with some effort, a design can be made to be apparent to the viewer.
In the majority of examples of these designs the image is carefully cut in to surface of a piece of acrylic or other transparent plastic using something like a rotary tool or even a sharp blade. But, the work can be tedious and demanding with some level of patience required. However, there are some methods that can make the process easier; but it takes some expensive equipment like a CNC router, laser cutter, or similar computer controlled device. But I do not have these in my DIY arsenal so I had to look for an alternative.
So, it finally occurred to me that it would be interesting to make the entire surface light up using strip light emitting diodes (LED’S), and utilize a transparent image that could be changed to alter the subject with the same piece of acrylic.
I tried several techniques including etching acrylic with acetone but the easiest and safest method was accomplished by simply sanding the surface uniformly. After some experimentation I finally settled on sanding the surface with 220 grit garnet paper which is readily available. In order to get a uniform and consistent surface, a circular motion was found to be better than directional sanding. So, using strip LED’s and a transparency made on an inkjet printer, the effect is what I was looking for.
After seeing the image I realized that the image could be made directly on the sanded acrylic with paint and a stencil. If the image needs to be changed we can simply remove the paint and make another image. Some questions remain and other images should be possible. For example, how about stamp pad images or transparent inks? So much to do and so little time!
Note: I am including the Amazon link as a guide as to what I used and is not an endorsement of these or any other manufacturer. As mentioned in the video, I would recommend getting strips without the silicone weather proofing surface to make connections easier. The Zitrades and other connectors are listed below the light strips. The link is here: