Origins of flare in x-ray image intensifiers.

The disk spread function of flare of an x-ray image intensifier (XRII) was measured using monoenergetic x rays. The signal-to-noise ratio at the center of the disks and the pulse height spectrum of the flare are also measured. These measurements are correlated with the physical construction of the XRII. A simple model of the XRII is developed which is used to identify the various sources of flare.