A near-infrared tip-tilt sensor for the Keck I laser guide star adaptive optics system

摘要: The sky coverage and performance of laser guide star (LGS) adaptive optics (AO) systems is limited by the natural (NGS) used for low order correction. This limitation can be dramatically reduced measuring tip tilt NGS in near-infrared where partially corrected LGS AO system stars are generally several magnitudes brighter than at visible wavelengths. We present design a tip-tilt sensor that has recently been integrated with Keck I telescope’s along some initial on-sky results. implementation involved modifications to bench, real-time control system, higher level controls operations software will also discussed. H2RG-based camera 0.05 arc second pixels. Low noise high sample rates achieved only reading small region interest, from 2×2 16×16 pixels, centered on an anywhere 100 diameter field. operates either Ks or H-band using light reflected choice dichroic beamsplitters located front OSIRIS integral field spectrograph.