SEMI-AUTOMATIC TLD Badge Reader

Semi Auto TLD Badge Reader TL1010S is a personal monitoring system, designed to read the TLD card (TL dosimeters) worn by radiation workers.
This Badge Reader system is designed using state of art electronics, improvised electro-mechanical system, embedded code and software to load and read the TLD cards for TL glow curve dose. System facilitates entry of ID number for the person and his dose record and glow curve can be stored in the system. TL dosimeter is heated by hot gas (N 2 ) jet to 280 o C using a SS heater assembly & TL output is recorded using PMT where integral of the current output is proportional to the dose.
It is a Thermoluminescent dosimeter based personnel monitoring system. Thermoluminescent dosimeters make use of the property of certain materials which absorb energy when exposed to X, Gamma or Beta radiation. On heating, the absorbed energy is released in the form of visible light. A plot of light intensity emitted against temperature is known as a glow curve. For a given heating rate, the temperature at which the maximum light emission occurs, is called the glow-peak temperature and it is characteristic, of the individual TL material (also called phosphor).
The quantity of the visible light emitted (TL output) is found to be proportional to the energy absorbed by the TL material.
The TLD personnel monitoring system essentially consists of two major parts: TLD badge and the TLD badge reader.
The TLD Badge Reader comprises of a plastic cassette containing three Teflon TLD discs (13.3mm and 0.8mm thick) that are mechanically clipped on to circular holes (12.0mm) punched in an aluminium card (52 x 30 x 1mm).
The TLD Badge Reader is designed to measure X, Gamma and Beta radiation dose. The metal filter combination (1mm Al + 0.9mm Cu) is provided to reduce the photon energy dependence of the TL discs. The TL badge reader is calibrated such that the TL output of the disc under the metallic filter reads directly the gamma radiation dose. .