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615 points thunderbong | 1 comments | | HN request time: 0.335s | source
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estimator7292 ◴[] No.45651413[source]
Tl:dw for how this works:

He scans one line at a time with a mirror into a photomultiplier tube which can detect single photon events. This is captured continually at 2MSample/s (2 billion times per second: 2B FPS) with an oscilloscope and a clever hack.

The laser is actually pulsing at 30KHz, and the oscilloscope capture is synchronized to the laser pulse.

So we consider each 30KHz pulse a single event in a single pixel (even though the mirror is rotating continuously). So he runs the experiment 30,000 times per second, each one recording a single pixel at 2B FPS for a few microseconds. Each pixel-sized video is then tiled into a cohesive image

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1. layla5alive ◴[] No.45664301[source]
Something is off here, 2MSamples/sec wouldn't be 2 billion times per second, that would be 2GSamples/sec