照明的不稳定性会引起视向速度测量误差,从而严重限制仪器精度的提高。光纤扰模是提高仪器照明稳定性的有效途径之一。为了给现有高精度色散光谱仪升级及新型高精度视向速度仪器设计提供可靠的实验参考,对单根圆形光纤、单根八边形光纤、圆形-八边形-圆形光纤串接系统、双圆形光纤扰模系统、圆形-八边形混合双光纤扰模系统和双八边形光纤扰模系统的近场和远场扰模性能进行详细的实验研究。实验结果显示:单根八边形光纤较单根圆形光纤具有更好的近场扰模性能,双光纤扰模技术可以有效改善近场和远场扰模性能,双八边形光纤扰模系统能同时具有良好的近场和远场扰模性能。实验研究了球透镜和双透镜两种双光纤扰模系统,球透镜系统通光效率约为55%,双透镜系统通光效率约为80%。

Radial velocity measurements errors caused by lighting instabilities severely limit the precision improvement in instruments; however, fiber scrambling is an effective method to enhance the stability of instrumental illumination. To provide a reliable experimental reference for the operation of a high resolution spectrograph upgrade and a new high precision radial velocity instrument design, the near field and far field scrambling properties of a single circular fiber, single octagonal fiber, circular-octagonal-circular fiber cascade connection system, double circular fiber scrambler, circular-octagonal hybrid double-fiber scrambler, and double octagonal fiber scrambler were studied in detail. The results showed that the octagonal fiber improved the near field scrambling compared to single circular fiber, the double-fiber scrambler could improve both near field and far field scrambling, and the double octagonal fiber scrambler optimally performed for both near field and far field. Furthermore, the prototypes of the double-fiber scramblers, including ball lens system and twin lens system, were also assessed herein. The throughput was observed to be 55% and 80%, respectively.