| 摘要 |
<p>An inner surface of the panel is formed to satisfy at least one of the following relationships: ZPH/LPH ≤ 0.050, and ZPV/LPV ≤ 0.050where LPH represents a distance from a center of the effective section to a long axis end of the effective section, LPV represents a distance from the center to a short axis end of the effective section, ZPH represents a fall of the effective section at the long axis end along the tube axis, and ZPV presents a fall of the effective section at the short axis end along the axis of the tube axis. At least one of each long side and each short side of a mask surface is curved such that a central portion thereof projects outwardly, and satisfies at least corresponding one of the following relationships: YML/LML ≤ 0.015, and XMS/LMS ≤ 0.015 where LML represents a distance from the short axis to each corner of an effective portion of the mask surface, LMS represents a distance from the long axis to each corner of the effective portion, YML represents a fall, along the short axis, between a point of each long side on the short axis and a corner of the long side, and XMS represents a fall, along the long axis, between a point of each short side on the long axis and a corner of the short side.</p> |
