Do you mean just the lens? There's one in each of those old school overhead tran... | Hacker News

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thekevan on Nov 4, 2020 | parent | context | favorite | on: Building an artificial sun that looks realistic [v...

Do you mean just the lens? There's one in each of those old school overhead transparency projectors. Those should be easy to find.

https://www.bhphotovideo.com/c/product/592006-REG/Dry_Lam_50...

arianvanp on Nov 4, 2020 [–]

No that's a lens.

A Frensel reflector doesn't led light through bit instead reflects the light. Basically the same idea as the parabolic dish, but as a flat sheet.

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