laser tripwire with arduino

Laser Tripwire Experiment with Phototransistor

o the first step toward building my tennis ball sensing board was to test the simplest iteration of the sensor concept: A single laser/sensor combo, that is tripped when an object passes between them, blocking the laser beam. Will an object breaking this beam cause enough of a drop in the phototransistor’s reading to create a digital signal that we can feed into a microprocessor?