Fotoselektrisk

Fotoselektrisk refers to a phenomenon and its applications involving the emission of electrons from a material when it absorbs electromagnetic radiation, typically light. This effect is the basis for many technologies that convert light into electrical signals or vice versa.

The photoelectric effect, first explained by Albert Einstein in 1905, demonstrates that light energy is quantized into discrete packets called photons. When a photon with sufficient energy strikes a material, it can transfer its energy to an electron, overcoming the binding forces and causing the electron to be emitted. The minimum energy required for this emission is known as the work function of the material.

This principle is fundamental to devices like photomultipliers, which amplify very faint light signals, and photodiodes, used for light detection and in solar cells for converting sunlight into electricity. Phototransistors and charge-coupled devices (CCDs) also rely on the fotoselektrisk effect for their operation in imaging and sensing applications. The sensitivity and wavelength range of fotoselektrisk devices depend on the properties of the photosensitive material used.