固态图像传感器的电离辐射响应均匀性

Ionizing Radiation Response Uniformity of Solid-State Image Sensors

研究并对比了6类电荷耦合器件和互补金属氧化物半导体图像传感器的辐射响应均匀性。设计辐射实验,对像素阵列中响应信号在不同统计区域内的像素值增量平均值和非均匀度进行分析与讨论,重点研究了各类固态图像传感器像素阵列全局、区域和代表像元的辐射响应均匀性。实验结果表明:在稳态γ射线辐射场辐照条件下,帧图像中的响应信号增量并非固定值;像素阵列各区域内响应信号的均匀性不因辐照剂量率的变化而变化,对于相同的图像传感器,辐射在任意帧图像中产生辐射响应信号的分布与像素阵列中任意像素在多帧图像中出现辐射响应的分布相同,但由于传感器的本底噪声存在差异,单个像元、区域像素的统计结果与全局存在偏差。本研究为提高基于图像传感器的γ射线辐射探测技术,实现无遮光条件下在线辐射探测提供了理论依据和数据支持。

Herein, the radiation response uniformities of six types of charge-coupled devices and complementary metal-oxide-semiconductor image sensors are studied and compared. Irradiation experiments are performed to investigate the average incremental pixel values and nonuniformities of radiation response signals in different regions of the pixel array. The radiation response uniformities of the global pixel array, regional pixels, and typical pixels in various solid-state image sensors are mainly studied. Results show that the incremental pixel value of the frame image under a steady-state gamma-ray irradiation is not a fixed value, and the uniformity of the radiation response signal in each region of pixel array is not affected by the radiation dose rate. For the same image sensor, the distribution of the radiation response signal in any frame image is the same as the radiation response distribution of any pixel, which is from the pixel array, in the multi-frame image. However, there is a deviation in the statistical results across the typical pixels, regional pixels, and global pixel array due to the difference of the sensor background noise. This study provides a theoretical basis and data support for improving the technology of gamma-ray radiation detection based on image sensors and realizing real-time radiation detection without shading.