HEATER STRUCTURE FOR CATHODE FOR CATHODE RAY TUBE

摘要

PURPOSE: A heater structure for a cathode for a cathode ray tube is provided to achieve improved efficiency of the heater, while reducing the amount of rod wire and costs. CONSTITUTION: A densely wound part serving as a heater part is formed by winding a heating wire(16) at a predetermined pitch on a mandrel wire(15). A triple wound part(E) serving as a lead part is formed by winding the heating wire at a predetermined pitch in a forward direction, winding the heating wire at a predetermined pitch in a reverse direction, and winding the heating wire again at a predetermined pitch in a forward direction. The densely wound part is divided into a first section(F) where the heating wire is wound at a predetermined pitch and a second section(G) where the heating wire is wound at a pitch wider than the pitch of the heating wire of the first section.