| 摘要 |
PURPOSE:To prevent damage due to heat of a primary radiator by providing an irregular reflecting plane reflecting irregularly the sun ray to the surface of a reflection mirror at the radio wave incoming side of a parabolic antenna for receiving a satellite broadcast. CONSTITUTION:In the parabolic antenna for receiving a satellite broadcast, a radio wave for a satellite broadcast is reflected on a reflecting member 10 of a reflection mirror 4 and collected on a focus on which the primary radiator 5 is placed. When the sun ray is overlapped with a ray in the incoming direction of the radio wave, the sun ray incoming to the reflection mirror 4 is reflected irregularly on an irregularly reflected plane 12 so that it is prevented that the ray is collected to a special position. Thus, the inconvenience such that the primary radiator or its surrounding is heated and a water-proof fixture 14 is molten into damage or the mechanical accuracy of the primary radiator 5 is degraded is prevented. |
