How to make a lithophane: from photo to a print-ready STL

A lithophane is a thin plate where the photo appears when light passes through from behind. From the front, without light, it looks like a grey relief. Against a window or an LED, it becomes the picture. Making one takes five minutes: the hard part is picking the right photo.

How it works

The part is the photo's negative in thickness. Where the image is dark, the wall is thick and blocks light; where it is light, the wall is thin and light passes through. In white PLA, 0.8 mm (light) to 3 mm (dark) is the classic range: under 0.6 mm the wall leaks too much light, over 4 mm nothing gets through.

Which photos work

• Good contrast. A washed-out photo becomes a uniform plate.
• A large face. Small detail disappears in the relief. A close portrait works better than a group photo.
• Background. A light background disappears; a dark one becomes a natural frame.

Step by step

1. Open the lithophane maker and drop the photo (JPG, PNG or WebP). It never leaves your computer: the relief is computed in the browser.
2. Choose the width in millimetres. Height follows the photo's proportions.
3. Flat, curved 90° or curved 180°. The curved one stands on its own and fits a cylindrical lamp; the 180° one is a half round, with an LED in the middle lighting it evenly.
4. Frame: 2 mm at maximum thickness keeps the piece rigid.
5. A resolution of 0.25 mm per pixel balances detail and file size. The preview rebuilds the relief on every change.
6. Download the STL, which comes out already in print position.

How to print it

• Standing up, with the thick wall on the bed. Lying flat, the layers show and the gradient is lost.
• Natural white PLA, no strong pigment. Translucent also works; black does not.
• 100% infill, 0.1 to 0.12 mm layers, low speed.

A classic gift. A 100 mm wide lithophane in an LED stand is one of the most requested printed objects. If you have no printer, the button at the end of the page sends the STL for a quote.