针对光经深截止滤光片衰减后，达到光子计数水平，其透过率难以用一般测量仪器测出的情况，设计了基于ICCD 的光子计数成像系统，介绍了系统的工作原理，硬件组成和图像处理所涉及到的软件算法，给出了利用单位时间内透过的光子数计算透过率的计算方法，并对一给定的日盲滤光片进行了透过率测试。在特定波长范围内，测试结果的数值相对实际情况偏小，测试结果的数量级与实际一致，表明该系统的测试稳定性较高。经过分析，系统最小可探测到每秒钟几百个光子，可用于经滤光片衰减后达光子计数水平的滤光片透过率测试。

A photon counting imaging system based on ICCD is designed to solve the problem that the transmittance is difficult to be measured by general measuring instruments when the light is cut by deep cut-off filter and reaches to the photon counting level. The operating principles of the system, hardware components, and software algorithms used for image processing are introduced. Furthermore, the algorithm used to calculate the transmittance from the number of photons transmitted per unit time is tested and the transmittance of a solar blind filter is calculated. Our studies reveal that, within a specific wavelength range, although the numerical result obtained using our algorithm is smaller than what is observed in experiments, the order of magnitude is the same in the two cases, thus indicating the high reliability of our system. Our analysis shows that our system can probe hundreds of photons per second, and thus, can be used for measuring transmittance in cases that require photon counting after reduction by filters.