COLOR CATHODE-RAY TUBE

摘要

PROBLEM TO BE SOLVED: To provide a shadow-mask color cathode-ray tube that hardly makes concave distortion on its shadow mask when a shock vibration is applied and that can display good quality images. SOLUTION: Electron-beam passing apertures of the shadow mask are formed with upper apertures etched from the panel side and lower ones etched from the electron-gun side, and those located in the periphery are controlled so that the ratio of upper etched quantity versus lower one is 1.8 and below. By adjusting balance of strength for compression stress between both sides of the shadow mask, its concave deformation can be prevented.