Patent ID: 7170220

Claim:
A shadow mask that comprises a mask body in which a large number of slots are made in the horizontal and vertical directions and that allows electron beams to form roughly rectangular beam spots on a fluorescent screen of a cathode ray tube, each one of the slots made in the mask body having a roughly rectangular backside opening on the side on which electron beams are incident, a roughly rectangular front-side opening on the side from which electron beams emerge, and a through-hole that connects the backside opening and the front-side opening with each other, the mask body having a center point situated in the center of the mask body plane, and a horizontal axis and two diagonal axes that pass through the center point and extend along the mask body plane, and of the multiple slots made in the mask body, the slots situated at least in those areas of the mask body that are surrounded by the horizontal axis and the two diagonal axes having such front-side openings that, of a pair of the upper and lower sides of the rectangular outline of the front-side opening of each slot, only the side situated on the side opposite to the horizontal axis side being inclined, relative to the horizontal axis, along the radiate line radiating from the center point toward the slot.