Researchers shrink camera to the size of a salt grain

 https://engineering.princeton.edu/news/2021/11/29/researchers-shrink-camera-size-salt-grain

"relies on a technology called a metasurface, which is studded with 1.6 million cylindrical posts and can be produced much like a computer chip... Aside from a bit of blurring at the edges of the frame, the nano-sized camera’s images were comparable to those of the traditional lens setup, which is more than 500,000 times larger in volume... could be easily mass-produced at lower cost than the lenses in conventional cameras"

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https://phys.org/news/2022-09-lensless-camera-3d-images-exposure.html

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