| 摘要 |
PURPOSE: A shadow mask is provided to prevent uniformity of the picture image from being lowered by forming outside portion larger than the center portion of the effective portion in vertical length of the slot. CONSTITUTION: A shadow comprises an effective portion including a plurality of slots, a circumference portion located around the effective portion and a mask skirt. The slots, a first vertical pitch(pv1), are regularly arranged to vertical direction at the center portion(A) of the effective portion. The outside portion(B) of the effective portion is the same as the center portion(A) of the effective portion in basic composition and arrangement. But a second vertical pitch(pv2) is larger than the first vertical pitch(pv1).
|
