# Evaluation of the Photon Transmission Efficiency of Light Guides Used in Scintillation Detectors Using LightTools Code

• Accepted : 2016.04.18
• Published : 2016.09.30

#### Abstract

Background: To optimize the photon transmission efficiency of light guides used in scintillation detectors, LightTools code, which can construct and track light, was used to analyze photon transmission effectiveness with respect to light guides thickness. Materials and Methods: This analysis was carried out using the commercial light guide, N-BK 7 Optical Glass by SCHOTT, as a model for this study. The luminous exitance characteristic of the LYSO scintillator was used to analyze the photon transmission effectiveness according to the thickness of the light guide. Results and Discussion: The results of the simulations showed the effectiveness of the photon transmission according to the thickness of the light guide, which was found to be distributed from 13.38% to 33.57%. In addition, the photon transmission efficiency was found to be the highest for light guides of 4 mm of thickness and a receiving angle of $49^{\circ}$. Conclusion: Through such simulations, it is confirmed that photon transmission efficiency depends on light guide thickness and subsequent changes in the internal angle of reflection. The aim is to produce an actual light guide based on these results and to evaluate its performance.

#### Acknowledgement

Supported by : National Research Council of Science &Technology

#### References

1. Kim CK, Kim HT, Kim JY, Lee CH et al. Replacement of a photomultiplier tube in a 2-inch thallium-doped sodium iodide gamma spectrometer with silicon photomultipliers and a light guide. Nucl. Eng. Technol. 2015;47:479-487. https://doi.org/10.1016/j.net.2015.02.001
2. Knoll GF. Radiation detection and measurement. 3rd Ed. New York. John Wiley & Sons Inc. 2000;252-253.
3. Lee JH, Kim HC, Jung SY. Analysis of indoor visible light communication environment based on LightTools. Trans. Korean Inst. Elec. Engine. 2015;64(6):935-939. https://doi.org/10.5370/KIEE.2015.64.6.935
4. Jung D, Sohn IB, Noh YC, Kim JH, Kim CH, Lee H. Fabrication of a multidirectional side-firing optical fiber tip and its numerical analysis. Korean. J. Opt. Photo. 2014;25(4):200-206. https://doi.org/10.3807/KJOP.2014.25.4.200
5. Han KT, Yoo WJ, Shin SH, Jeon DY et al. Development of fiberoptic radiation sensor using LYSO scintillator for gamma-ray spectroscopy. J. Kor. Sensors Soc. 2012;21(4):287-292.
6. Mao R, Zhang L, Zhu RY. Emission spectra of LSO and LYSO crystals excited by UV light, X-ray and $\gamma$-ray. IEEE Trans. Nucl. Sci. 2008;55(3):1759-1766. https://doi.org/10.1109/TNS.2008.921877

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