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A laser pointer at 2B FPS [video]

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Re: A laser pointer at 2B FPS [video]

#91

Post by hi41 »

estimator7292 wrote: post #33

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 p…

Can we not find why the strange behavior of a double split experiment occurs using this setup?

Re: A laser pointer at 2B FPS [video]

#92

Post by SAI_Peregrinus »

hi41 wrote: post #91
estimator7292 wrote: post #33

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 p…

Can we not find why the strange behavior of a double split experiment occurs using this setup?

No, all the light seen as in "beams" is scattered off fog. That scattering is a measurement from the perspective of QM.

Re: A laser pointer at 2B FPS [video]

#93

Post by SAI_Peregrinus »

easygenes wrote: post #82
nerdsniper wrote: post #64

Earlier quoted context omitted.

Do you have any better recommendations?

They’re not one of the big 3, but Rigol are pretty much the only scope co actively marketing models to hobbyists / individuals: https://www.rigol.com/europe/news/company-news/mho900-releas...

Also Siglent.

Re: A laser pointer at 2B FPS [video]

#94

Post by jonah »

generuso wrote: post #69
nerdsniper wrote: post #56

Earlier quoted context omitted.

Honestly I think if we each wrote a nice personal letter to Keysight they’d probably gift him one in exchange for the YouTube publicity. Several other electrical engineers on YT get free $20-50k keysight scopes not just for themselves, but once a year or so to give away to their audience members. And yes, this person could make use of it. His videos are among the highest quality science explainers - he’s like the 3B1…

What this experiment does is very similar to how an ordinary LIDAR unit operates, except that during a LIDAR scan the laser and the receiver are always pointed in the same direction, while in this demonstration the detector is scanning the room while the laser is stationary and is firing across the room. But in principle, a LIDAR could be reconfigured for the purposes of such demonstration. If one wants to build the…

And "Flash LIDAR" captures every pixel all at once. (But the frame rate is limited by how quickly the buffer can be read out and the sensor readied for the next frame.)

Re: A laser pointer at 2B FPS [video]

#96

Post by ck2 »

light doesn't move at a fixed rate

light moves AT the speed of causality in that frame of time

causality appears to have a MAXIMUM limit in this universe in an "empty" void

but every time you hear a story of how they "slowed down light" what they actually did is make causality more complex in a dense medium, so slower

Re: A laser pointer at 2B FPS [video]

#98

Post by alanh »

SCLeo wrote: post #36
estimator7292 wrote: post #33

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 p…

Thanks for the explanation. Honestly, your explanation is better than the entire video. - I watched it in full and got really confused. I completely missed the part where he said the light is pulsing at 30kHZ and was really puzzled at how he is able to move the mirror so fast to cover the entire scene.

Huh. I watched a lot, but not all, of the video, and I thought he made it clear early on that he was stitching together 1px videos & repeating the event for each pixel (about a million times for that 720p result)

Re: A laser pointer at 2B FPS [video]

#99

Post by db48x »

MBCook wrote: post #90
db48x wrote: post #48

Earlier quoted context omitted.

He explained that. His inexpensive oscilloscope _can_ trigger from the second channel, but only at one billion samples per second. Where’s the fun in that?

Oh that’s right. I saw this video earlier in the week and forgot that. Thanks.

You’re welcome.
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