by picture on 5/23/25, 6:33 PM with 14 comments
by alexbock on 5/23/25, 7:36 PM
by Xmd5a on 5/24/25, 12:38 AM
https://web.archive.org/web/20230914035459/https://caoyuan.s...
A $500 DIY near-IR spectrometer that would sell for $10,000, Yuan Cao
>The placement of the cylindrical lens (position & angle) affects the focal point for different wavelength. I did not do a rigorous calculation here —— I simply resorted to a trial-and-error method to figure out the optimal placement.
by joshvm on 5/23/25, 7:58 PM
by contingencies on 5/24/25, 2:44 PM
https://www.amazon.com/View-Camera-Technique-Leslie-Stroebel...
Somebody in Dongguan once introduced me to the Korean running the iPhone lens assembly production systems (it was outsourced; ~COVID). IIRC they had 13 lens elements at the time and each assembly was characterized and digitally corrected according to its specific optical characteristics. Fascinating guy to talk to over beer. He moved east after that, someplace near Shanghai IIRC.
by elikoga on 5/23/25, 7:23 PM
Show HN: Torch Lens Maker – Differentiable Geometric Optics in PyTorch (63 days ago) 2025-03-21
https://news.ycombinator.com/item?id=43435438by NKosmatos on 5/23/25, 9:51 PM