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Fourier Optics used for Optical Pattern Recognition

Fourier Optics used for Optical Pattern Recognition

Huygens Optics
5 HN recommenders · discussed 2021–2025
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About this video

Huygens Optics explains the Fourier transform and shows how a lens performs one optically. A DLP projector is used as a Fourier filter to do simple pattern recognition on lithographic character patterns.

Why it appears in the archive

Recommended as one of the best explanations of Fourier transforms and a clear demo of analog optical computing.

AI-generated summary and labels from the source dataset; verify important details against the video. Source & credits.

From the Hacker News discussion

jstrieb · 2021-09 · strong rec

I was introduced to this idea in a really cool video about using Fourier Optics for optical pattern recognition.[0] The video happens to have one of the best explanations of Fourier transforms I've yet encountered. [0] [VIDEO]

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orlp · 2022-06 · strong rec

For a somewhat related topic (analog image recognition), for those interested, I can highly recommend this video: [VIDEO]

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jstrieb · 2022-08 · strong rec

Reminds me of this really cool video about using Fourier Optics for optical pattern recognition.[1] The video happens to have one of the best explanations of Fourier transforms I've yet encountered. 1: [VIDEO]

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ulnarkressty · 2022-06 · rec

An even better one - holding an image at the focal point of a lens produces its Fourier transform at the focal point on the other side of the lens[0]. It is used for "analog" pattern matching[1]. There is an interesting video explaining this on the Huygen Optics Youtube channel[2]. [0] - [LINK] [1] - [LINK] [2] - [VIDEO]

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CamperBob2 · 2024-05 · rec

You could think of a lens as a "Fourier transformer," not in the LLM sense directly but in the sense of something that executes a Fourier transform. See the excellent videos by Huygens Optics including this one: [VIDEO] entitled "Fourier optics used for optical pattern recognition." Having established that, well, it's not hard to imagine that something that's good at running Fourier transforms is probably good for other situations where you need to run a lot of dot products in parallel. That, in turn, should sound like an awfully familiar problem...

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infogulch · 2025-01 · rec

Huygens Optics has a great video "Fourier Optics used for Optical Pattern Recognition". He starts with explaining the Fourier Transform wrt audio, then demonstrates a physical filter that screens the resulting convolution pattern to identify matches. Very cool: [VIDEO]

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aaaaaaaaaaab · 2022-08 · reference

Optical pattern recognition is an established field. Here's a simple version via Fresnel zone plates: [VIDEO]

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Balgair · 2024-01 · reference

Upping a cousin comment. [VIDEO] Adding that, again, optics is a difficult and frustrating field. Don't worry that you're struggling to connect it. It took me a few years in an optics lab working hands on with light every day to really come around.

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