Calibration of spatially nonuniform sensitivity for a spectral line emission measuring system

An apparatus for space- and time-resolved measurements of the spectral line emission from glow discharge plasmas is described. It utilizes two stages of microchannel plate image intensifiers and a computer-assisted data acquisition system. The image intensifiers have a significant level of dark noise, and their sensitivity is spatially nonuniform. The effect of the dark noise is reduced significantly by signal averaging. A calibration procedure using a movable stable source is followed so that quantitative measurements can be obtained despite the spatial nonuniformity. >