<title>A Survey Of Large Screen Displays For C<formula><sup><roman>3</roman></sup></formula> Applications</title>

Abstract

systems. Techniques applicable to large screen display systems include projection cathoderay tubes, light valves and large area direct view flat -panel devices. The operationalcharacteristics, information on existing product line equipment and a description of newlarge screen devices, which are just entering the market or are in An advanced state ofdevelopment, are presented herein. This material is based upon the results of a survey ofmanufacturers of large screen display equipment for military and commercial applications.It has been augmented by on -site discussions with cognizant engineering personnel andmarketing managers. Improvements to existing equipment, cost information (both initial andoperating), and new technological advances in the field over the last five years arehighlighted.IntroductionGenerally, there is no universally accepted definition of a large screen display device,however, a definition can be proposed on the basis of screen viewing area. The viewing areaof the largest available cathode ray tube is approximately one square meter. Thus, anydisplay with a viewing area greater than one square meter will be considered a large screendisplay.In any system application, the need for a large screen display should be justified on thebasis of its advantages to the user. For example, in Military C systems large screendisplays are used to present critical information that can be viewed by groups of people,including command personnel, in large room applications. The systems are configured toallow personnel to move around, within reasonable limits, and still view the display. Whenit is necessary to meet these requirements, the large screen display can be considered acost effective and useful device. Once the justification for a large screen display hasbeen established, a system can be selected and implemented. In past systems a variety oftechniques have been proposed and tried, but it has been difficult, even within the presenttechnology, to develop a large screen display device which compares favorably with thesmaller conventional CRT terminals. The basic problems involve the cost of providing alarge screen display at a brightness, information rate, and resolution equivalent to that ofthe smaller CRT terminal whether or not color and /or monochrome display images are required.Large screen devices suitable for Military C3 applications in rooms with dispersedaudiences and ambients of 15 to 30 foot -candles must meet certain requirements to perform