Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
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Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#2Very cool, I was not aware that LEDs could be used like that. I wonder how sensetive this technique can get.
Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#3You might also want to watch this video that demonstrates a 2D proximity sensor using an LED array. It works without a laser pointer, using the fingertips alone is good enough for it:
https://cs.nyu.edu/~jhan/ledtouch/index.html
A few days ago, a user here also commented on how LEDs work both ways and how he used this effect to automatically adjust the brightness of an LED to ambient light. You can find that comment here:
Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#4You might also want to watch this video that demonstrates a 2D proximity sensor using an LED array. It works without a laser pointer, using the fingertips alone is good enough for it: https://cs.nyu.edu/~jhan/ledtouch/index.html A few days ago, a user here also commented on how LEDs work both ways and how he used this effect to automatically adjust the brightness of an LED to ambient light. You can find that comment…
Very impressive, i love this kind of stuff.
“…and in my next video I’ll show you how to bake a pizza in your freezer.”
Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#5You might also want to watch this video that demonstrates a 2D proximity sensor using an LED array. It works without a laser pointer, using the fingertips alone is good enough for it: https://cs.nyu.edu/~jhan/ledtouch/index.html A few days ago, a user here also commented on how LEDs work both ways and how he used this effect to automatically adjust the brightness of an LED to ambient light. You can find that comment…
I've wondered how hard it would be to hack old LED signs into OSC touch control surfaces.
Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#6I see they did a trick in the code: Because binary literals were added late in C++14, it seems they used some library which defined 256 constants like B00000000 = 0, B00000001 = 1, ..., B11111111 = 255.
Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#7You might also want to watch this video that demonstrates a 2D proximity sensor using an LED array. It works without a laser pointer, using the fingertips alone is good enough for it: https://cs.nyu.edu/~jhan/ledtouch/index.html A few days ago, a user here also commented on how LEDs work both ways and how he used this effect to automatically adjust the brightness of an LED to ambient light. You can find that comment…
Very impressive, i love this kind of stuff. “…and in my next video I’ll show you how to bake a pizza in your freezer.”
Just swap a couple of pipes to reverse the heat pump. Nothing can possibly go wrong.
Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#8Made me think of Eli Yablonovitch, “A great solar cell also needs to be a great LED.” RIP Alta Devices.
Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#9Very cool, I was not aware that LEDs could be used like that. I wonder how sensetive this technique can get.
People have made half-duplex, 2-way single-fiber links this way.
With reverse-biased diodes, you are operating in photoconduction mode. If tightly-coupled to a fiber optic, and with a quantum efficiency of say, 10%, that would mean for every 10 photons which come in, you get 1 electron charge of current flow.
IIRC there are people who paint e.g. 1N4444 diodes with black paint to minimize opto-induced leakage.
Re: Using a laser pointer and a matrix LED as a two-dimensional input device (2010)
#10I see they did a trick in the code: Because binary literals were added late in C++14, it seems they used some library which defined 256 constants like B00000000 = 0, B00000001 = 1, ..., B11111111 = 255.
Note quite. See [1]