| 摘要 |
PURPOSE:To attempt uniformity of the quality of a picture screen by specifically selecting the area ratio of the central electron beam thru holes perforated into the first and second electrodes to the thru hole sections on both sides. CONSTITUTION:The central electron beam thru hole section 21b of an eliptical forme is perforated through an electrode 20 in a larger scale than those of electron beam thru hole sections 21a and 21c, of an eliptical form on both sides within the area ratios of 1.2-1.35. This selection of area ratio can reproduce any picture on the color picture tube screen with excellent uniformity of quality and high fidelity. |
