GB731124A - Improvements in or relating to cathode ray tubes - Google Patents

Abstract

731,124. Cathode-ray tubes. WESTING- HOUSE ELECTRIC INTERNATIONAL CO. June 23, 1953 [July 30, 1952], No. 17344/53. Class 39 (1). A cathode-ray tube comprises a gun for producing a single beam and a separating electrode structure 26, Fig. 3, for splitting the beam into three independently controllable beams comprising three plates 28 joined at a common edge to form a Y-shaped structure the three arms of which are equally spaced, the plates extend parallel to the gun axis, and their common junction point lies along the gun axis. The beam passes successively through ratio section 22, Fig. 2, beam splitting section 26, Fig. 3, and positioning section 30, Fig. 4. In the ratio section it is deflected towards whichever of independently-energized plates 23, 24, 25 is momentarily more positive, and is consequently split unequally by splitting electrodes 28, the latter tending to deflect the beams outwardly. In the positioning section 30 plates 32 are positive with respect to plates 34 to provide independent radial deflection adjustments for the three beams. The beams can be independently intensity-modulated. Electrodes 28, 34 can be integral. A focusing coil (not shown) renders the three beams parallel to the tube axis. The fluorescent screen may produce a single colour or preferably plural colours as in a colour television receiver.