An optical projection system for information data display

The paper discusses generally the desired characteristics of visual display devices and specifically describes a highly versatile, uniplanar, electro-optical rear projection-type information data display unit. The design of this unit features a plurality of optical systems, each with an independently activated light source, focused upon a common viewing screen. Each optical system may thus be used to display either alphanumeric, symbolic or word messages (complete or progressive), and/or colour information. The theory of operation, construction, operational characteristics and performance of the device are discussed.