中国1.8 m太阳望远镜(Chinese large solar telescope,CLST)致力于对太阳偏振的高精度及高灵敏度测量。然而其系统本身会引入仪器偏振,并且在望远镜运行的过程中,仪器偏振会随其指向的变化而变化。这就降低了系统的测量精度。因此,需要...中国1.8 m太阳望远镜(Chinese large solar telescope,CLST)致力于对太阳偏振的高精度及高灵敏度测量。然而其系统本身会引入仪器偏振,并且在望远镜运行的过程中,仪器偏振会随其指向的变化而变化。这就降低了系统的测量精度。因此,需要一个偏振标定单元对其仪器偏振进行标定。为此,本文对偏振标定的原理和方法进行了研究,并且给出了针对CLST的偏振标定单元设计方案。展开更多
The phase diversity wavefront sensor is one of the tools used to estimate wavefront aberration, and it is often used as a wavefront sensor in adaptive optics systems. However, the performance of the traditional phase ...The phase diversity wavefront sensor is one of the tools used to estimate wavefront aberration, and it is often used as a wavefront sensor in adaptive optics systems. However, the performance of the traditional phase diversity wavefront sensor is limited by the accuracy and dynamic ranges of the intensity distribution at the focus and defocus positions of the CCD camera. In this paper, a modified phase diversity wavefront sensor based on a diffraction grating is proposed to improve the ability to measure the wavefront aberration with larger amplitude and higher spatial frequency. The basic principle and the optics construction of the proposed method are also described in detail. The noise propagation property of the proposed method is also analysed by using the numerical simulation method, and comparison between the diffraction grating phase diversity wavefront sensor and the traditional phase diversity wavefront sensor is also made. The simulation results show that the diffraction grating phase diversity wavefront sensor can obviously improve the ability to measure the wavefront aberration, especially the wavefront aberration with larger amplitude and higher spatial frequency.展开更多
文摘中国1.8 m太阳望远镜(Chinese large solar telescope,CLST)致力于对太阳偏振的高精度及高灵敏度测量。然而其系统本身会引入仪器偏振,并且在望远镜运行的过程中,仪器偏振会随其指向的变化而变化。这就降低了系统的测量精度。因此,需要一个偏振标定单元对其仪器偏振进行标定。为此,本文对偏振标定的原理和方法进行了研究,并且给出了针对CLST的偏振标定单元设计方案。
文摘The phase diversity wavefront sensor is one of the tools used to estimate wavefront aberration, and it is often used as a wavefront sensor in adaptive optics systems. However, the performance of the traditional phase diversity wavefront sensor is limited by the accuracy and dynamic ranges of the intensity distribution at the focus and defocus positions of the CCD camera. In this paper, a modified phase diversity wavefront sensor based on a diffraction grating is proposed to improve the ability to measure the wavefront aberration with larger amplitude and higher spatial frequency. The basic principle and the optics construction of the proposed method are also described in detail. The noise propagation property of the proposed method is also analysed by using the numerical simulation method, and comparison between the diffraction grating phase diversity wavefront sensor and the traditional phase diversity wavefront sensor is also made. The simulation results show that the diffraction grating phase diversity wavefront sensor can obviously improve the ability to measure the wavefront aberration, especially the wavefront aberration with larger amplitude and higher spatial frequency.
