Construction of a composite thin-element TLD using an optical-heating method

Area of Science:

• Radiation detection and measurement
• Materials science for dosimetry

Background:

• Thermoluminescent dosimeters (TLDs) are crucial for radiation monitoring.
• Existing TLD systems may have limitations in speed, sensitivity, or stability.

Purpose of the Study:

• To develop a composite TLD system with a high-speed optical-heating reader.
• To evaluate the performance characteristics of the novel TLD system.

Main Methods:

• Development of a composite TLD with four thin Li2B4O7:Cu or CaSO4:Tm elements.
• Utilizing an optical-heating method with IR radiation for rapid element heating (0.8 sec to 350°C).
• Characterization of TLD system performance, including detection limits, energy dependence, and stability.

Main Results:

• Detection limits of 3 mR (Li2B4O7:Cu) and 0.1 mR (CaSO4:Tm).
• Energy dependence similar to dose-equivalent curves, with minor deviations.
• High stability over 1,000 cycles, low residual dose (0.1%), and resistance to contamination.
• Fast processing time (3 hr/500 dosimeters) for the automatic reader.

Conclusions:

• The developed composite TLD system offers high speed, sensitivity, and stability.
• Suitable for various monitoring applications including personnel, gate, and environmental dosimetry.
• The thin Li2B4O7:Cu element is effective for skin dose monitoring.