TEST AND EVALUATION OF ELECTRONIC IMAGE GENERATION AND PROJECTION DEVICES VOLUME III - EVALUATION OF PROJECTION SCREENS

摘要

This report presents data from an evaluation of seven types of projection screen surfaces to determine which surface best meets the requirements of visual simulation for astronautical flight training. In order to evaluate the various screen surfaces in terms of their brightness and the angle through which incident light is reflected, methods of measurement were devised which compared each screen to a given reference surface. Two materials were tried as the reference surface, the traditional matte white surface of magnesium carbonate and a special type of white paint applied to masonite. The Latter surface reflected the more uniform pattern of light, but proved difficult to duplicate due to the great care needed to apply the paint evenly. Thus the report recommends continued use of magnesium carbonate block as the standard reference for display screen measurements. The test data on the seven screen surfaces indicates a wide variation in display characteristics. Apparently the user must accept an appropriate compromise between brightness and viewing angle—the more confined the viewing angle the brighter the display. It was also noted that flaws in the screen surface are particulary apparent in the more directive brighter screen materials. It is thus essential that screens employing such materials be manufactured with extreme care.