These are art pieces that I like to call Light Boxes, due to their similar structure to an illustrator’s light box. I’ve made several of these over the past couple of years as gifts for friends and family.
The lightboxes are 17×10 inches in the front and were originally 2 inches thick, but with refinement I have reduced them down to 1.25 inches thick. They have several mounting options- picture frame style wall mounting, a decorative chain hanging wall mount, and 3D printed stands for shelving or table display. The structure is made of black acrylic, and the front surface is made of a translucent ‘LED acrylic’ which looks matte black while the box is off, but reveals a beautiful animated colorful design when turned on.
Below you can see the inside of one. The inner surface of the LED acrylic has a matboard stencil that determines the shape of the design. Matboard is excellent for this situation because it is very good at masking off light and it is easy to cut with a laser cutter. 5v addressable LED strips are placed around the edges of the stencil and powered by an Arduino Nano. They use a USB-C port for power and come with an outlet adapter.
Above you can see a work in progress clip of programming the lighting. I write custom Arduino code to suit the stencil shape and LED strip layout for each box. This tree had the most complex code of any lightbox project for a couple reasons.
First, the light behavior changes between the trunk and the treetop. Colors are chosen randomly to start at the roots of the tree and travel up the length of the trunk. Once at the top, the color spreads to a few random locations in the leaves, where it stays until another color replaces it. You can see the final effect in action to the right.
The second challenge with this one was writing a 1 dimensional RGB graphics buffer. I needed to do this because the colors travelling up the trunk vary in speed, so they can overlap. I wanted the overlapping colors to blend together smoothly and additively, so rather than writing colors directly to a pixel they are written to the buffer where additive color operations can be performed efficiently. After the final blended colors are calculated in the buffer they are written to the LED strip.
Above is the most recent box I made with a butterfly stencil. The programming for this one was much more straight forward, but the LED strip mounting on the inside was more complicated. I mounted the LED strips very tightly around the perimeter of the butterfly to ensure nice even lighting. This meant some delicate work, especially in the corners of the wings. Thanks to this detailed mounting work, I was able to use a simple rainbow wave along the entire length of the LED strip and still get an excellent color pattern out of it. If you look closely you can see an interesting effect where different colors run along the inside edges of cells in the stencil. To the right you can see a zoomed in example of this. This is caused by the slight depth of the stencil casting shadows from different angles. All of the boxes do this, but it’s more prominent here thanks to the tight LED strip mounting.
The Maui box below is another more recent project I gave as a Christmas present. This was the point where I really felt like I had refined the formula for the lightboxes. The unique part of this one was making Maui stay pink, and having the rainbow wave spread outwards from there.
Lastly is this “Drink Mead and Eat Salmon” one I did for a friend who is very into Nordic and Viking culture. This was the first lightbox I ever built and the one and only time I hand-cut the stencil out of the matboard. Originally I wanted to add Nordic runes all the way around the edge, but time constraints and hand cramps stopped me from going that far. Luckily after this one I have been able to laser cut the stencils, saving a lot of time and pain. In this clip you can also see the unlit box before the lighting turns on.
I really enjoy making these, and my hope is to start selling them eventually. After several iterations on the design and building methods I’m able to make them quick and efficiently. It’s a lot of fun coming up with new stencil designs and figuring out how I want the color pattern to look. Making them as gifts is also very satisfying because I can customize them very specifically to whoever I’m giving it to. I love seeing the reaction when they open it- usually some slight confusion as they try to figure out what it is, and then the total joy when they plug it in and turn it on for the first time.