photon

plural photons

1. particlenatural sciencesThe quantum of light and other electromagnetic energy, regarded as a discrete particle having zero rest mass, no electric charge, and an indefinitely long lifetime. It is a gauge boson.

   The single-imaging optic of the mammalian eye offers some distinct visual advantages. Such lenses can take in photons from a wide range of angles, increasing light sensitivity. They also have high spatial resolution, resolving incoming images in minute detail.

   2013 July-August, Fenella Saunders, “Tiny Lenses See the Big Picture”, in American Scientist