i am writing a lab report into an experiment i did using a photodiode to detect alpha particles. I am curious however as to how a photodiode actually works. The alpha particles are emitted from the source, they hit the diode and then what happens? Its somehow changed into an electrical signal that comes up on the screen of my computer at a particular energy but how does it get there? Also theres a pre-amp and an amplifier being used which i am not sure about either.. Any help would be greatly appreciated.