| 摘要 |
<p>A second panel and a third panel are arranged on both sides of a first panel in a width direction, the panels have an identical length and are parallel to each other so that a difference in level is provided between the first panel and the second panel or the third panel with a gap, a width of the first panel is three times or more a width of the second panel and is three times or more a width of the third panel, and when a width of an entire panel unit as a total of the widths of the first to third panels is 1, a ratio of the difference in level between the front surface of the first panel and the front surface of the second panel is 0.05 to 0.1.</p> |
