GB1319203A - Deformographic display system - Google Patents

Abstract

1319203 Cathode-ray tubes INTERNATIONAL BUSINESS MACHINES CORP 27 July 1971 [29 Oct 1970] 35062/71 Heading H1D [Also in Division H4] An electrostatically deformable member 40, suitable for use in a Schlieren optical system for example, comprises a deformable dielectric solid layer 42, e.g. of silicone rubber, in intimate contact on one side with a rigid dielectric substrate 41 and on the other side with a deformable conductive material 43. In one mode of use the member is placed within a cathode-ray tube adjacent the faceplate 11 thereof, substrate 41 being of mica which may be coated with SiO, SiO 2 , MgO or MgF 2 to enhance its resistivity, so that a first electron gun may provide an electrostatic pattern 44, 45 thereon. It is said that point charges and uniformly charged areas both produce a unidirectional deflection of material 43 towards the charged areas, whereas in former devices wherein the conductor 43 was rigid and deposited on plate 11 away from layer 42 they produced oppositely directed deflections. A second "flood" electron gun is provided to erase the charge pattern, or the first gun may provide both functions. The member 40 may be light transmissive (43 is Au or Al) or reflective (43 is Ag or Al). In a further embodiment, Fig. 5 (not shown), a further layer of conductive material is laid down on the exposed face of substrate 41 (mica or glass), one or both the conducting layers being in the form of parallel strips, radial or alpha-numeric patterns for example and selected areas are addressed in or out of a vacuum to selectively deform layers 42, 43.