I am looking for laser sensor to measure velocity of fast moving bullet/projectile traveling through barrel.
I have a bullet of 5mm length and it would cut the laser for just 5- 20 microseconds. The sensor need to be fast enough to give trigger to oscilloscope with this kind of small intervals...
I'm doing the project of hand vein visualizer but the vein images result are not appear clearly so I bought the IR LED transmitter and receiver. I tried to power on the LEDs. I don't know why they didn't work but they not light up. Can anyone help or share any circuit for me to try?