Pocket ionization detectors are common dosimetry devices. Radiation sensitive photographic film detects gamma, and x-rays. The radiation affects the emulsion similar to light. The developed films are compared to standards to establish the radiation exposure. Film badges are common dosimetry devices that use this method.
Luminescent detectors measure exposures to neutrons.
Arriving radiation changes the energy content of solids in the detectors. The energy change causes them to emit light. The amount of light is proportional to the energy change. In scintillation detectors incoming radiation strikes a thin layer of crystals or a solution of organic materials that produce light. Light output is proportional to the radiation absorbed.