Help with Velocity Counter Project Using Photo Diode

[Ali Inam]

Hi, I am making up a Velocity Counter using a photo diode. I have planned it to be in the following way:

I will be having two ends, on both of those ends I will be having photo diodes on one side and laser lights falling on the diodes from exactly opposite sides. Now I will make a toy car move, once the toy car intercepts the first light beam, I want my counter to start the time immediately and as soon as it intercepts the other beam, I want it to stop.


Can anyone guide me please.

Thanks...!

 

[berkeman]

Hi, I am making up a Velocity Counter using a photo diode. I have planned it to be in the following way:

I will be having two ends, on both of those ends I will be having photo diodes on one side and laser lights falling on the diodes from exactly opposite sides. Now I will make a toy car move, once the toy car intercepts the first light beam, I want my counter to start the time immediately and as soon as it intercepts the other beam, I want it to stop.


Can anyone guide me please.

Thanks...!

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