引言在光发射阴极上可复现光学象,如电视场允许,合成的电子发射图样就能成为光子图样的准确再现。这种电子发射图样,只能按照随空间和时间变化的光的图样而变化。可用电子束产生一维时间扫描,然后用电子束摄象管,光导摄象管和析象管等许多方法加以放大。电场可简单地由电于在电场中加速或电子在波导中倍增放大,直接聚焦在萤光屏上,而产生放大了的光电阴极上的可见图象,如现在的象增强管就是如此。然而,在超过几个微米的波长上,敏感 Introduction Optical images can be reproduced on a light-emitting cathode, as the television field permits, and the resultant electron-emitting pattern can be reproduced accurately as a photon pattern. This pattern of electron emission can only vary with the pattern of light that varies with space and time. The electron beam can be used to generate a one-dimensional time scan and then amplified using many methods, such as electron beam cameras, light-guide tubes, and resolves. The electric field can simply be accelerated by an electric field or doubled electronically in the waveguide to focus directly on the screen, resulting in a visual image of the enlarged photocathode, as is the case with current intensifiers. However, it is sensitive at wavelengths in excess of a few microns