Collimated light's light whose rays are nearly parallel, and therefore will spread slowly as it propagates. The word's related to "collinear" and implies light that doesn't disperse with distance (ideally), or that'll disperse minimally (in reality). A perfectly collimated beam with no divergence can't be created due to diffraction, but light can be approximately collimated by a number of processes, for instance by means of a collimator. Collimated light's sometimes said to be focused at infini… (More on Collimated)