ABSTRACT
An image intensifier (II), or image converter as it is sometimes called, is a photoelectronic vacuum tube device that receives a low-light-level input image and transforms it in to a high-light-level output image. In operation, this photoelectronic device produces an enhanced image at its output phosphor screen of a faint input image that is focused on its photocathode. The vacuum is a requirement for the types of IIs discussed herein because the prime detector, i.e., the part of the II that transforms the low-light-level input image into an electron image, the photocathode, is only useful in a high vacuum environment. In the sections that follow, the various components and technologies related to IIs will be described in detail, and the performance characteristics of various practical IIs, when used in a variety of cameras and systems, will be reviewed.
