Optimization of the imaging properties of image tubes

The electron lens sections of image converters and image intensifiers are genera- lly designed using a computer model. The model developed at TESLA-Vacuum Engineering El,Ictron Optics Laboratories has proved very accurate in predicting the major lens cha- racteristics, for example position and shape of the image surface, magnification, dis- tortion and resolution. An analytical approach to the numerical calculation of the effect of curvature of the photocathode on imaging parameters of the triode electrode system is outlined. A semi-analytic relations is derived to analyse the imaging pro- perties and their dependence on certain geometric and voltage tube parameters.