Evaluation of Signal-Generating Image Tubes

The evaluation of signal-generating image tubes or television camera tubes is considerably more difficult than is the evaluation of image-intensifier devices, described in Chapter 3 of this volume, although the overall action of a camera tube and of the entire system in which it functions is essentially the same as that of an image intensifier. That is, like the image intensifier, the television system accepts a radiation image formed on an input photosurface by an objective lens and produces an analogous brightness image on a phosphor screen to be viewed by a human observer, although both the display and the observer may be many thousands of miles from the television camera and the scene.