TL;DR: For Valentines Day, I made a lithophane—a 3D object which reveals an image when light is shined through it. The operating principle is basic—different “pixels” are created since thicker areas block more light.
Lithophanes are really cool. Essentially, they’re 3D photos that physically encode pixels of an image by varying the amount of material. Thinner sections of the lithophane allow more light to pass through. I discovered a simple to use, yet highly customizable online lithophane generator at http://3dp.rocks/lithophane/. Upon making this discovery, my mind immediately went to the perler project I worked on last year… I saw I could reuse most of the components (back plate, switch, LED backlight), only making a new front plate. Since I designed the perler project housing in Onshape using top-down design principles, all the modifications only took a few minutes to complete and export for printing.
It took me three tries to finetune my print settings. In the first print, I inadvertently made the image inverted:
For the second print, I ended with a lot of blobs on our faces. Clearly this was because the nozzle dwelled a bit too long on the top surfaces since I printed this part flat on the bed:
To correct for this, I reoriented the part on the print bed. I was worried about the part falling over (hence my original print orientation), so I added a really large brim to keep it rooted:
The third time really did turn out to be the charm, and I was very pleased with how it turned out:
There’s a ton of ways in which the lithophane idea can be expanded and improved upon. First, I need to redesign the housing unit to incorporate the switch and battery. Others on the internet have wrapped lithophanes around objects like cylinders to make custom lamps, trophies, and other neat projects. The possibilities are endless… as you can see in the summary photo below, you can use pretty much any light source and have the images turn out well:
I’m excited to play around more with this type of stuff!