| 摘要 |
PURPOSE:To blow a cooling air directly to the surface of a dielectric airtight window plate, by delivering the cooling air through air holes furnished at the bottom of a ring-form adjustment groove close to the said window plate. CONSTITUTION:A cooling air is led in or exhausted through air holes 64, 76, and 84a formed at the bottom of a ring-form adjustment groove C close to a dielectric airtight window plate 34. Therefore, the cooling wind is blown to the surface of the dielectric airtight window plate 34 securely. Consequently, as well as the cooling function of the dielectric airtight window plate 34 is improved, a leakage of highfrequency waves through a cooling air inlet hole 83 and exhaust hole 98 can be restricted effectively. |
