Input-output light field

An input-output light field describes how light interacts with a system, such as a lens or optical device. The input light field is the pattern of light rays approaching or entering the system, including their directions and intensities. The system then modifies this light—focusing, redirecting, or scattering it—resulting in an output light field. Understanding this transformation helps in designing optical devices, capturing or manipulating images, and improving imaging technologies. Essentially, it details how an optical system changes the distribution of light from its incoming state to its outgoing state.