 Optically transparent chips- Simulate “point detector” in medical physics applications
- Reusable hundreds of times
- Independent of dose rate up to 100 MGy/s
- Long term response retention
- Nearly tissue-equivalent
- ±15% sample-to-sample uniformity
- Repeatability to within 2% or better.
Approximate tissue equivalence:
- Z - 8.14 (LiF )
- Z - 7.64 (AIR)
- Z - 7 .42 (TISSUE)
Consistent, well-controlled and repeatable procedures are key to successful TLD. Variations in annealing temperature will affect dosimeter sensitivity.
When using TLDs, vacuum tweezers should always be used. Mechanical tweezers and fingers should not be used.
Specifications
Radiations Measured:
Photon, energies >5 keV
Neutron, thermal to 100 MeV
Electron/beta, energies >70 keV
Range: 10 µGy to 1 Gy (1 mrad to 100 rad) linear
1 Gy to 20 Gy (100 rad to 2000 rad) supralinear
Tissue equivalence: Nearly tissue equivalent
Fading: <20% in 3 months without thermal treatment
<5% in 3 months using preheat or glow curve deconvolution
Batch uniformity: ±15% STD DEV from the batch mean, tighter
on special request
Residual TL Signal: <0.2% of reading, over the range, without annealing
Repeatability: for 1 mGy (100 mrad) 137Cs doses,
<2% STD DEV of 10 sequential measurements.
Reuse: More than 500 per dosimeter with <10% sensitivity change.
Threshold: <10 µGy (1 mrad) based on 2.26 STD DEV of 10 repeat readings of an unexposed dosimeter.
Material: Lithium Fluoride LiF:MgTi
Density: 2.64 gm/cc
Size: 0.125” sq. x 0.035” (3.2 mm2 x 0.9 mm)
Temperature of Main TLD Glow Peak: 195o C
Sensitivity at Cobalt 60 Relative to LiF: 1.0
Energy Response 30 keV/Cobalt 60: 1.25
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