在用于从半空间测量装置 - 对应于2π的立体角 - 下一个，其被布置在与低惯性的帮助下辐射可透过的圆顶的至少一个电磁辐射，高灵敏度的检测器进行测定，其特征在于，被施加交变光方法是上面的辐射可透过的 半球罩2相同或不同的训练，嵌套，kalottensegmentförmige调制器提供，其中至少一个围绕所述两个调制器的共同的垂直轴线转动。 此外，两个相同或不同的执行调节剂可绕与无论是在相同方向或相反方向上以相同或不同的速度共同轴线。 通过应用交变光Vertahrens的用于从2π来电磁辐射显著较高的测量精度能在相反来实现迄今常规的立体角测量，广泛用于直接光方法。 尽管如此，出来的半空间的电磁辐射可以被测量的显着惯性比使用两个旋转，kalottensegmentförmigen调制器之前时较差。

In a device for measuring of the half - space corresponding to a solid angle 2π - coming, electromagnetic radiation of at least one arranged with help from a radiation-permeable dome, low inertia, high-sensitivity detector is measured, the alternating light method is used, are the radiation-transmissive calotte two same or different like design, arranged inside one another, kalottensegmentförmige modulators provided, of which at least one rotating around the common vertical axis of the two modulators. Further, the two same or different from each executed modulators can rotate about the common axis with either the same or different speeds in the same direction or in opposite directions. By using the alternating light method for measuring from a solid angle of 2n coming electromagnetic radiation can be achieved in contrast to the usual, used in large scale direct light method a considerably higher accuracy. Yet this can be measured significantly inertia poorer than before when using the two rotating, kalottensegmentförmigen modulators that coming from the half-space, electromagnetic radiation.