Gain model for microchannel plates

It is shown that microchannel plates (MCPs) tend to act as if they were discrete stage electron multipliers with a fixed number of stages or dynodes if a plausible assumption is made regarding the behavior of the secondary electrons emitted from the semiconducting sidewalls of tubular channel electron multipliers under the grazing incidence conditions predominantly encountered in these multipliers. The shape of the resultant predicted gain-voltage transfer characteristic for the MCP fits well with experimental data, confirming the assumption made and permitting the use of curve matching techniques to determine such important MCP parameters as the average number of active dynodes, the gain per stage, the crossover potential for the MCP wall material, the transit time through the multiplier, etc.