A friend sent me this simple design for a raman spectrometer [1].
And some 3D-printable cage optics for when alignment is really important [2].
[1]: https://hackteria.org/wiki/images/a/a0/MobPhone_RamanSpec_20...
[2]: https://www.sciencedirect.com/science/article/pii/S246806721...
It seems like an ESP32 camera could handle everything pretty cheaply, why is this not a thing you can just buy for $50 on Amazon yet?
Actual recommended technique: grind it https://hackaday.com/2023/11/16/a-3d-printed-grinder-for-pri...