Abstract
A possible method of making a large screen display is to apply a virtual image system with a large concave mirror. A large concave parabolic mirror of high quality to be used for this purpose, can be made inexpensively with rotation method.
In this case, plastic material, such as epoxy resin which hardens at room temperature, is formed into parabolic shape within a rotating dish. A mirror of 920 mm diameter and 1150 mm focal length, which has been fablicated by this method, shows sufficiently good characteristics for a virtual image display system.
