结合理论分析与实验测试，研究了在可见光脉冲输入条件下频率以及第二片微通道板与阳极之间电势差对微通道板光电倍增管动态范围的影响。研究结果表明：随着信号光脉冲频率的增大，微通道板壁面电荷补充不充分致使阳极输出偏离线性，并逐渐趋于饱和。当输入可见光脉冲宽度为50 ns，频率为500 Hz时，阳极的最大线性输出达到2 V（即40 mA）；当输入光频率增加到1 000 Hz，阳极输出在1 V（即20 mA）时线性偏离程度达到10%以上；当输入光频率增加到5 000 Hz，阳极输出在0.3 V（即6 mA）时线性偏离程度达到约15%。随着第二片微通道板与阳极之间电势差的增大，阳极最大线性输出电压呈现波动性变化而非与其呈线性关系。当第二片微通道板与阳极之间的电势差在200 V左右时，阳极线性输出电压达到峰值，随着电势差不断增大，阳极线性输出电压开始出现波动，在电势差为500 V左右时达到第二个峰值，这主要是由于极板间电场强度与空间电荷效应共同作用的结果。该研究可为提升微通道板光电倍增管的动态范围提供指导，便于其应用于强辐射脉冲测量、激光通信等领域。

Microchannel Plate Photomultiplier Tube (MCP-PMT), as a high-performance photodetector, has been widely used in various detection experiments in recent years. In previous studies, people mainly focused on improving the sensitivity and temporal resolution of optoelectronic detection devices, while ignoring the key factor of high linearity. With the continuous development of the demand for large dynamic detection, in-depth research and development of MCP-PMT with large dynamic range has become an urgent need for current research.The dynamic range of MCP-PMT is related to many factors, such as the intensity and frequency of input visible light, the material of the microchannel board, and the voltage values applied to each part of MCP-PMT. This article mainly starts from two aspects: the input light pulse frequency and the potential difference applied by the backend of MCP-PMT, and delves into the reasons why the output electrons of MCP-PMT deviate from normal linear multiplication.By combining theoretical analysis and experimental testing, the influence of the repetition frequency of pulse light signals and the potential difference between the second microchannel plate and the anode on the dynamic range of MCP-PMT was studied in detail. When the input light pulse width is 50 ns and the repetition frequency is 500 Hz, the maximum linear output of the anode can reach 2 V (i.e. 40 mA); when the repetition frequency increases to 1 000 Hz, the linear deviation degree reaches more than 10% when the anode output is 1 V (i.e. 20 mA); when the input light frequency further increases to 5 000 Hz and the anode output reaches 0.3 V(i.e. 6 mA), the degree of linear deviation has reached about 15%. As the electric potential difference between the second microchannel plate and the anode increases, the maximum linear output voltage of the anode shows fluctuating changes. When the electric potential difference between the second microchannel plate and the anode is around 200 V, the linear output voltage of the anode reaches its peak. As the electric potential difference increases, the linear output voltage of the anode begins to fluctuate, reaching the second peak at a electric potential difference of around 500 V.In this article, we investigated the influence of the frequency of pulse input light and the electric potential difference between the second microchannel plate and the anode on the dynamic range of MCP-PMT, and obtained two conclusions through experimental verification: 1) As the pulse input frequency increases, the output voltage of MCP-PMT will detach from the linear region earlier. 2) As the potential difference between MCP2 and the anode increases, the maximum linear output voltage of MCP-PMT does not simply vary monotonically, but exhibits a constantly fluctuating trend in resistance. On this basis, further exploration was conducted on the factors that constrain the dynamic range of MCP-PMT, namely insufficient wall charge supplementation and interference from space charge effects. When the frequency of the input pulse is high, the constraint on the dynamic range of MCP-PMT is mainly related to the former; when the electric potential difference between the second microchannel plate and the anode increases, due to the complex situation of a large number of secondary electrons transferring between the plates to the anode, the dynamic range will be affected by the space charge effect and cannot be directly proportional to the electric field strength.