GB999649A - Improvements in or relating to colour television - Google Patents

Abstract

999,649. Colour television tubes. W. H. THACKER. Sept. 17, 1963 [Sept. 19, 1962], No. 35612/62. Heading H1D. A colour television display screen comprises colour phosphor strips in the repeating sequence G-R-B printed on a film base 1 and having superimposed thereon three series of printed conductive strips 3g, 3r, 3b, each series being in matching register with phosphor strips of a particular colour and insulated from the other two series by interposed insulating material 4, 5. During operation, the screen is scanned with a single electron beam, and the three series of conductive strips are subject to voltage modulation in accordance with chrominance signals to effect colour shade modulation, the beam being more or less repelled by a voltage bias applied to each series to cause maximum, partial or zero fluorescence of the corresponding phosphor strips. The electron beam may be modulated in accordance with monochrome signals per se, but preferably is modulated with some modification of contrast whereby luminance modulation is provided for each of the three basic colours of the phosphor strips. However, in the former case, and with no voltage bias applied to the conductive strips, the screen may be used for monochrome display. The base 1 may be a polyester film which may be cemented to a cathode-ray tube faceplate. The conductive strips of each series are connected at their ends and may be printed in colloidal silver, the three series being separated by thin, sprayed-on, insulating layers 4, 5. The phosphor and conductive strips may be straight, or a waved-line form may be used where a vibrant-beam technique is employed.