| 摘要 |
A picture display device comprises a cathode ray tube (1) with an elongated display screen (8) and a deflection system (9) for deflecting electron beams. The display screen is substantially rectangular with a long and a short axis. The line scanning direction is parallel to the long axis of the display screen. The cathode ray tube comprises aneck portion and between the screen and the neck portion a cone portion (3, 3a). This cone portion has an aspect ratio (ratio of x and y dimension, x/y ratio), which is near the neck below unity and changes to above unity closer to the screen as a function of z. |
