| 摘要 |
The side surfaces of the spacer or intermediary layer have a shape differing from a flat surface at right-angles to its width sides. At least two, and pref. three such intermediary layers are prepared at the same time by milling of the edges and of a track in a plate. The plate has a thickness which is at least of the same dimension as that of the intermediary layer, and a width which is at least two, and pref. three times greater than the width of the intermediary layer. |
