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Where is the video? That's what I'm looking for
There's some cool videos at the end of this article. Not the article posted, but similar concept if I understood correctly. Observation of laser pulse propagation in optical fibers with a SPAD camera https://www.nature.com/articles/srep43302 http://i.giphy.com/3og0IQ5k6PP9KspN9m.gif (gif version of one of the mov files)
Earlier quoted context omitted.
Umm good luck getting enough photons to see anything. Shot noise
So shoot at 1 quad, and average 1000 frames to one output frame? Light will still be moving less than 1mm per frame.
Earlier quoted context omitted.
For 635nm red laser light, you'd need to be sampling somewhere in the order of 9.4 x 10^14 times a second to get two samples per cycle. Based on roughly 300000000m /635nm x2 but then the question comes down to how many cycles make up a photon and does that question even. Make sense in the first place.
>9.4 x 10^14 Can you explain how did you get this number for the red wavelength? Also can we fundamentally "see" a photon?
I was using 635nm as the wavelength (basically a red laser). That gives you:
3 x 10^8 / 635 x 10^-7 = 4.7 x 10^14
Which should be about 470 terahertz (4.72 x 10^14) give or take a bit. To sample that "perfectly" you'd need to sample at twice the frequency or about 940 terahertz or (9.4 x 10^14).
As to your second question, I know that there are single photon detectors. Past that, you've got me. I don't know if that can be classified as "seeing" or not. As to size, there's https://briankoberlein.com/2015/04/14/thats-about-the-size-o... but that might or might not make sense.
That's about the limit of what I'm willing/able to say on the subject.
“It’s an achievement in itself,” says Jinyang Liang, the leading author of this work, who was an engineer in COIL when the research was conducted, “but we already see possibilities for increasing the speed to up to one quadrillion (1015) frames per second!” Just getting started... o_O
Honest question, what can be seen at one quadrillion fps that 10 trillion cannot already see? This question is out of pure ignorance and wonder, like "Why would you ever want to move faster than a horse". But this is at a scale I just cannot think in anymore.
Let's say that you have a train moving at a constant velocity, v. Then a switch is flipped and turns on a light that is in the exact center of the room. Which wall does the light hit first? [0]
Seen from on the train[1]: might as well be seen as if you were in a stationary room. The light hits both walls at the same time.
Seen from off the train[2]: The speed of light is constant. Since the train is also moving the light can't travel at v+c. So it hits the back wall, which is traveling towards the light at v, first.
This is a famous thought experiment and in practice would be difficult to perform, even with such a camera. But I'm saying it because it illustrates that we can actually observe relativistic effects. Things act extremely differently than what we're used to when small or moving fast. Assuming you had a really high resolution, something like length contraction could be observed, and measured, in normal conditions.
So there are actually a lot of weird things going on that we wouldn't be aware of. These ultra high speed cameras allow us to observe some of these strange phenomena.
[0] https://en.wikipedia.org/wiki/Relativity_of_simultaneity
[1] https://upload.wikimedia.org/wikipedia/commons/c/ce/Traincar...
[2] https://upload.wikimedia.org/wikipedia/commons/7/72/Traincar...
