Novel Full-Color Cathode Ray Tube for Miniature-Display Applications

A novel cathode ray tube (CRT), using a single electron gun and a movable screen, has been developed that now enables miniaturization of a full-color CRT with the same excellent viewing quality customarily found in larger-screen CRTs. In addition to the benefits of wide viewing angle, high resolution, high brightness, color purity, and full gray-scale features that are characteristic of CRTs, the need for only one electron gun is expected to also result in reduced power consumption and lower cost. The movable-screen design, a significant improvement over the earlier moving-shadow-mask version (1), is considered feasible for CRTs ranging in size from less than 1 in. (2.5 cm) to greater than 5 in. (12.7 cm). A unique and highly advantageous feature of the improved design, which is described in greater detail below, is the elimination of spatial offset of the color pixels. One obvious application with great commercial potential is in helmet-or head-mounted displays for a wide variety of virtual-reality systems. Other applications include portable or hand-held devices where compactness, low power, high resolution, and high brightness are desirable or advantageous, such as TVs, monitors for VCRs, and viewfinders for camcorders, especially for outdoor use.