Dosemeter

A novel dosimeter comprises a solid-state element holder carried on a circular slide, a collecting electrode for collecting an electron current emitted from the element excited by irradiation, and a light source for heating the element. The holder and collecting electrode are housed in a gas chamber through which a gas flows for ionization. When the element in its holder is irradiated at the outside of this dosimeter, it is carried into the gas chamber by means of a circular slide to received the light energy from the light source. Electrons are then emitted from the element by the thermal stimulation of the optical irradiation in accordance with the irradiation quantity of the radiation. These electrons act to ionize the gas around the element the ionization current is detected through the collecting electrode. A high voltage may be applied across the element and collecting electrode for a multiplicating ionization. Since the element is heated by optical irradiation, heating time can be reduced and the structure of the dosimeter can be simplified to allow for easy replacement of the element. (Ohno, Y.)