| 摘要 |
PURPOSE:To achieve a high quality picture image, by making such that the open hole region of the shadow mask is larger at the electron gun side than the phosphor face side while the width in the direction of horizontal axis at the thick section of the mask in the open hole region is longer than the width in the direction of the horizontal axis at the phosphor face side. CONSTITUTION:The open hole section of the shadow mask is formed of a bridge section having the thickness of board (T) of 0.3mm., the arranging pitch in the direction of X-axis of 0.75mm., in the direction of Y-axis of 0.81mm. and the longitudinal width of the slit open hole viewed from the phosphor face side of 0.12mm. and a bank section having the width (d) between the short directions of the slit open hole viewed from the phosphor face side of 0.25mm. or formed into a slit open hole having sufficient large width G(0.56mm.) when compared with the width D(0.50mm.) of the open hole region 61 at the phosphor face side. While a short side wall is formed into a slit open hole having small width W(0.20mm.) when compared with the width W(0.22mm.) of the open hole region 63 at the electron gun side. The region where the thickness (t) of the etched section 65 at the side of the region 63 is 0.05-0.08mm. is formed at the position departed approximately 0.25-0.30mm. from the central axis 71 of the small diameter hole. Consequently a high quality picture image can be formed. |
