Home-Corporate News-Thermoluminescence personal dosimeter has become an indispensable and important tool in modern radiation protection system
Thermoluminescence personal dosimeter has become an indispensable and important tool in modern radiation protection system
Update time: 2026-01-06 Number of clicks: 304
Thermoluminescent personal dosimeters have become an indispensable tool in modern radiation protection systems due to their special physical principles and performance advantages. As materials science advances (such as the development of new phosphors), its sensitivity and application range are expected to be further expanded.
Analysis of the basic working principle of thermoluminescence personal dosimeter:
1. Electron excitation and trap capture: When a thermoluminescent material is exposed to ionizing radiation, its internal electrons absorb energy and jump from the valence band to the conduction band, forming free electrons and holes. Some of the electrons are captured by "trap" energy levels in the crystal structure during migration (these traps are formed by impurities or lattice defects), while holes are trapped by the opposite energy level. This process stores radiation energy in the form of electron-hole pairs, creating a potential signal proportional to the cumulative radiation dose.
2. Heating luminescence and signal conversion: During measurement, the instrument heats the material to a specific temperature (usually several hundred degrees Celsius) through the heating system. The trapped electron gains enough energy to escape the trap, recombine with the hole and release a photon. The intensity of the released optical signal is directly related to the initial absorbed radiation energy. Subsequently, the photomultiplier tube converts the optical signal into an electrical signal, and then the data processing unit calculates the cumulative radiation dose value. This process follows a second-order kinetic model and can be computer automated to resolve the spectra to improve accuracy.
3. Material characteristics and calibration: Commonly used thermoluminescent materials such as LiF:Mg and Ti crystals have stable trap energy levels to ensure long-term signal preservation. Before use, annealing treatment is required to eliminate residual doses, and energy response calibration is used to achieve normalized measurement of different energy radiation, thereby adapting to the monitoring needs of multiple rays.
Precautions for using the thermoluminescent personal dosimeter:
1.Environmental control
-Avoid various temperatures (>40℃ or <-10℃), humidity (<80RH) and mechanical shock to prevent component performance degradation.
-Stay away from strong electromagnetic fields (such as MRI equipment) to prevent signal interference.
2. Operating specifications
- Keep the front of the dosimeter facing the radiation source when wearing it to avoid underestimating the dose due to exposure to the back.
- It is prohibited to disassemble or modify the structure of the dosimeter by yourself to avoid damaging the sealing.
3. Maintenance and calibration
-Clean the dosimeter casing regularly and wipe it with a soft cloth. Corrosive solvents are prohibited.
-Send it to a legal metrology agency for calibration at least once a year to ensure traceability.
4.Data management
- Establish personal dose files to continuously monitor the same batch of components required by the same person.
- When a single dose is found to exceed the investigation level (such as 5mSv), the investigation procedure will be initiated immediately.
5. Special scene processing
-Neutron sensitive components (such as LiF(n,α)) are required in neutron radiation environment.
-After short-term high-intensity radiation missions, give priority to fast-response TLDs (such as CaSO:Dy).