Simulation of time response performance for microchannel plates with different pore geometries

MCPs are electron multiplication devices composed of thin sheets with arrays of micropores. Due to their high electron gain, fast response, and excellent spatial/temporal resolution, MCPs have been extensively employed in photoelectric detection, particle physics, and high-speed imaging. Among these characteristics, time response is a critical parameter determining the suitability of MCPs for high–temporal-resolution applications. The time resolution of individual micropore in MCP can reach the picosecond scale, however, the micropores within MCPs exhibit diverse cross-sectional geometries, such as circular, elliptical, and square. At present, systematic analyses of the time-response mechanisms associated with different channel geometries remain limited. In this study, numerical simulations were performed for circular, elliptical, and square cross-sections under equal area constraints. Geometric analysis combined with finite element methods is employed to calculate the internal electric field distribution and its uniformity within each channel type. Under consistent modeling conditions, transit time and transit time broadening are extracted as key indicators of temporal response. These parameters are then analyzed in relation to geometric features and electric field variations. Simulation results reveal that circular cross-sections, benefiting from uniform electric field distribution, exhibit the shortest transit time and minimal broadening. In elliptical channels, temporal response degrades progressively with decreasing roundness. Square cross-sections, characterized by a roundness of 0.785, show intensified electric fields at the corners, resulting in the longest transit time and poorest time resolution. As the operating voltage increases from 500 V to 1000 V, transit time broadening decreases across all three geometries. This work elucidates the intrinsic relationship among MCP geometry, internal electric field, and time response, providing theoretical insights for structural optimization and the development of high temporal-resolution detection systems.