#Physics
Scientists achieve single-photon imaging over 200 kilometers
Scientists achieve single-photon imaging over 200 kilometers
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Robert Biloute - on diaspora-fr.org reshared this.
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Robert Biloute - on diaspora-fr.org reshared this.
Richard Healy
in reply to Stuart Richman • • •Stuart Richman
in reply to Stuart Richman • • •DavïÐ Låzårµ§ (Pluspora is westing 😢)
in reply to Stuart Richman • • •Robert Biloute - on diaspora-fr.org
in reply to Stuart Richman • • •Robert Biloute - on diaspora-fr.org
in reply to Stuart Richman • • •So unless you have an active volcano in the line of sight the background should be fairly quiet at those wavelength (well obviously you should not try to image the sun directly 😛).
DavïÐ Låzårµ§ (Pluspora is westing 😢)
in reply to Stuart Richman • • •Robert Biloute - on diaspora-fr.org
in reply to Stuart Richman • • •Robert Biloute - on diaspora-fr.org
in reply to Stuart Richman • • •Robert Biloute - on diaspora-fr.org
in reply to Stuart Richman • • •Practically, you see a pulse on the screen each time a photon is detected, this is the current pulse generated in the detector. At visible wavelength in daylight, you'll have so much photons you will not see anything unless you're very very very fast.
But here thanks to thin frequency band and I guess other tricks, they manage to get a background count of some hundreds photons per seconds, which is very low and detectable individually by a fairly slow electronics.
DavïÐ Låzårµ§ (Pluspora is westing 😢)
in reply to Stuart Richman • • •Richard Healy
in reply to Stuart Richman • • •