Can we see single photons?

Light is made of photons, and our night vision is limited by the ability of our visual system to detect these photons. In some ways, our eyes approach the fundamental physical limit for light detection, being able to detect light flashes of less than a dozen photons.



0:00 Introduction
0:37 Photoreceptors and photons
1:52 Experiment
3:22 Rhodopsin
3:59 Signal to noise
6:00 Limitations
6:55 Conclusion


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