| 摘要 |
PURPOSE:To maintain constantly the optimum conditions for the relation between the resolving power and the throughput, by setting the conditions for solar slits in accordance with desired resolving power. CONSTITUTION:A shutter 3 which is driven by a shutter switch 4 for setting an exposure time and one of solar slits 5a, 5b and 5c are placed along the X-rays path 2 from an X-ray source 1. The slits 5a, 5b and 5c are provided with a multiplicity of fine apertures and have different angular apertures with each other. The slits 5a, 5b and 5c are selected by an exposure control unit 11a. In such a manner, the optimum conditions for the relation between the resolving power and the throughput can be maintained constantly. |
