Low-Light-Level Devices: A Designers' Manual

摘要

The purpose of this report is to present in orderly fashion the key factors in the design, analysis, and characterization of low-light-level devices. The parameters of interest are those that have the greatest effect on the transfer of information from the scene before the lens of the television camera to the human looking at the picture tube. Part I examines specifications for low-light-level devices. Part 2 discusses criteria for image quality. Part 3 examines the human visual process and optical aids to that process under conditions of low illumination. Part 4 discusses the image intensifier as a device to aid vision at low light levels and lists the parameters of a variety of available image intensifiers. Part 5 introduces television camera tubes and develops the concepts leading to display signal-to-noise ratio, Rosell's signal-to-noise ratio at the display. It is this, the authors believe, that is the most powerful means of evaluating 'resolution,' a term usually used loosely and incorrectly. Part 6 compares camera tubes on the basis of lag and display signal-to-noise ratio and discusses adverse factors such as 'burning' and 'blooming.' Part 7 sums up with some brief comments on important tube parameters and their specification. (Author)