A *shape* on a 3D printer bed. One side has lenticular ridges on it.
https://files.mastodon.social/media_attachments/files/111/060/075/819/294/395/original/9a311e9f4f00d3e5.jpeg
The slat based collimators are such a pain, I've decided to go for it and try making lenses instead. I think a 3D printed mould will be good enough - the layer height is very much smaller than the LED size, and a bit of scattering is actually desirable. I'm printing this vertically so the lens profile gets the high resolution. It's going to be precarious when it reaches the top.
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