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Operational life is one of the important parameters to evaluate second and super second generation image intensifiers. It
can be used not only to monitor manufacturing technique in product line, then the technology on photocathode
processing, MCP degassing and MCP producing can be adjusted promptly, but also to eliminate the image intensifiers
which have hidden risk on operational life as early as possible. Recently gating image intensifiers are used widely,
method to estimate the operational life of gating image intensifier related to its practical operate mode and working
condition need to be established urgently. The least square method to analyze the operational life test data in product line
was introduced in this paper. Now the data can be analyzed with convenient statistic analyze function on Excel. Using
"worksheet function" and "chart wizard" and "data analysis" on Excel to do the least square method calculation,
spreadsheets are established to do complex data calculation with worksheet functions. Based on them, formulas to
monitor the technology parameters were derived, and the conclusion that the operational life was only related to the
decrease slope of photocathode exponential fit curve was made. The decrease slope of photocathode sensitivity
exponential fit curve and the decrease percent of the exponential fit photocathode sensitivity can be used to evaluate the
qualification of the operational life rapidly. The mathematic models for operational life prediction on image intensifier
and gating image intensifier are established respectively based on the acceptable values of the decrease percent of the
exponential fit photocathode sensitivity and the expecting signal to noise ratio. The equations predicting the operational
life related to duty cycle and input light level on gating image intensifier were derived, and the relationship between
them were discussed too. The theory foundation were made herein, so the user can select proper gating image intensifier
type just considering the practical using condition and make the best design and application project. The paper gave
guidance on data analyzing in product line and using gating image intensifier.
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