Shim Hyeong Seok, Park Haewook, Lee Jae Sung
Interdisciplinary Program of Bioengineering, Seoul National University, Seoul, Republic of Korea.
Integrated Major in Innovative Medical Science, Seoul National University Graduate School, Republic of Korea.
Phys Med Biol. 2021 Oct 14;66(20). doi: 10.1088/1361-6560/ac2b81.
In this study, we propose a simple gain compensation technique for silicon photomultiplier (SiPM)-based positron emission tomography detectors, using a temperature sensor that automatically controls the bias voltage of the SiPM depending upon the ambient temperature. The temperature sensor output, for which the temperature coefficient can be controlled by the input voltage, is used as one end of the bias voltage. By adjusting the temperature coefficient, the proposed gain compensation method can be applied to various SiPMs with different breakdown voltages. As a proof of concept, the proposed method was evaluated for two scintillation detector setups. Applying the proposed method to a single-channel SiPM (ASD-NUV3S-P; AdvanSiD, Italy) coupled with a 3 mm × 3 mm × 20 mm LGSO crystal, the 511 keV photopeak position in the energy histogram changed by only 1.52% per 10 °C while, without gain compensation, it changed by 13.27% per 10 °C between 10 °C and 30 °C. On a 4 × 4 array MPPC (S14161-3050HS-04; Hamamatsu, Japan), coupled with a 3.12 mm × 3.12 mm × 15 mm 4 × 4 LSO array, the photopeak changes with and without gain compensation were 2.34% and 20.53% per 10 °C between 10 °C and 30 °C, respectively. On the wider range of temperature, between 0 °C and 40 °C, the photopeak changes with and without gain compensation were 3.09% and 20.89%, respectively. The energy resolution degradation of SiPM-based scintillation detectors operating at temperatures was negligible when the proposed gain compensation method was applied.
在本研究中，我们提出了一种用于基于硅光电倍增管（SiPM）的正电子发射断层扫描探测器的简单增益补偿技术，该技术使用一个温度传感器，根据环境温度自动控制SiPM的偏置电压。温度传感器的输出用作偏置电压的一端，其温度系数可通过输入电压进行控制。通过调整温度系数，所提出的增益补偿方法可应用于具有不同击穿电压的各种SiPM。作为概念验证，针对两种闪烁探测器设置对所提出的方法进行了评估。将所提出的方法应用于与3 mm×3 mm×20 mm LGSO晶体耦合的单通道SiPM（ASD-NUV3S-P；意大利AdvanSiD公司）时，能量直方图中511 keV光电峰位置在10℃至30℃之间，每10℃仅变化1.52%，而在没有增益补偿的情况下，每10℃变化13.27%。在与3.12 mm×3.12 mm×15 mm 4×4 LSO阵列耦合的4×4阵列MPPC（S14161-3050HS-04；日本滨松公司）上，在10℃至30℃之间，有增益补偿和无增益补偿时的光电峰变化分别为每10℃ 2.34%和20.53%。在0℃至40℃的更宽温度范围内，有增益补偿和无增益补偿时的光电峰变化分别为3.09%和20.89%。当应用所提出的增益补偿方法时，基于SiPM的闪烁探测器在不同温度下工作时的能量分辨率退化可忽略不计。
