# How does a photo detector detect?

by einstein2603
Tags: detect, photo
 Emeritus Sci Advisor PF Gold P: 9,772 Hello again einstein, All 'photodetectors' operate using the photoelectric effect (or variants of). Basically, the photoelectric effect can be explained using quantum physics. Have you heard of the wave-particle duality of light? The photoelectric effect was the first source of firm evidence for the particle nature of light. Basically, light can be considered as a massless particle called the photon which has an energy of $E = hf$. This site is very useful and should have all the information you need. If you have any questions, you can post them here http://hyperphysics.phy-astr.gsu.edu...on.html#quacon Regards, ~Hoot