GB1354683A - Cathode ray tube apparatus - Google Patents

Abstract

1354683 Cathode-ray display tubes SANDERS ASSOCIATES Inc 19 April 1971 [2 April 1970] 59878/73 Divided out of 1354681 Heading H1D A flat cathode-ray tube wherein deflecting means are provided for scanning an electron beam in two directions before it enters a space between a fluorescent screen and a beamdirecting electrode which directs the beam on to the screen, comprises at least two fluorescent screens to provide a colour display or a plurality of independent monochrome diplays. In Fig. 7 a translucent support 90 is provided with two different phosphors 101 and 102 on a serrated surface and with a third phosphor 100 on a plane surface, these being excited by respective electron beams 93, 95 and 97 which are directed on to the screens by electrodes 98 and 99, at least one of which is transparent. In modifications, a flat support is coated on both sides with luminescent material, and both sides are scanned, either by a single electron beam (Fig. 6, not shown) which can be deflected to one side or the other, or by two electron beams (Fig. 5, not shown). If the support is opaque this provides two independent displays, and if the support is transparent the display may be in two colours. In another modification, Fig. 4 (not shown), a flat opaque support coated on each side with luminescent material is disposed at an angle between two parallel beam-directing electrodes. In a further modification, Fig. 8 (not shown), four luminescent screens with associated conductive coatings are arranged in Z formation between two electron beams, and any of the four screens may be scanned by connecting the surface opposed to it to a repelling potential; a stack of such screens may be provided and used to give a three dimensional display.