620mm薄镜面主动光学望远镜校正实验

Correction experiment of 620mm thin mirror active optics telescope

  • 摘要: 对620mm 口径薄镜面主动光学望远镜进行了主镜面形校正和系统波像差校正实验。主镜支撑结构由轴向36 个主动支撑点和侧向6 个被动支撑点组成, 其中轴向33 个支撑点用于主动校正,3 个作为虚拟硬点用于控制主镜空间位置;利用研制的Shack-Hartmann(S-H)传感器作为检测设备,采用最小二乘法计算校正力。实验中在对系统校正能力测试的基础上,选择了中低频Zernike 像差参与校正。通过将S-H 传感器固定在主镜曲率中心位置, 完成了主镜在不同俯仰角下的面形校正, 将初始状态约0.6RMS 校正到/12~/15RMS。而后通过平行光管发出的星点目标,对望远镜系统进行了波像差校正,使系统波像差从初始约0.65RMS 校正到约0.2RMS,分辨率由18 lp/mm 提高到45 lp/mm。

     

    Abstract: For 620 mm diameter active optics telescope, surface error correction for primary mirror and system wavefront aberration correction experiment were carried out respectively. The support system of primary mirror consisted of 36 axial active supports and 6 lateral passive supports, in which 33 axial supports were used for active correction, and 3 were used as dummy hard points for controlling the position of primary mirror. The Shack-Hartmann wavefront sensor was used as testing equipment and the least square method was used to calculate the active corrective forces. In the experiment, low frequency Zernike terms were selected for correction through analyzing the correction ability of the system. Through fixing the S-H sensor at the curvature center of primary, the mirror surface error correction experiment was carried out at different elevation, and around 0.6RMS surface error of the initial state can be corrected to /12-/15 RMS. Then the wavefront error of the telescope system was corrected using the star object of collimator, around 0.65RMS of the initial state was corrected to 0.2RMS, and the resolution is improved from 18 lp/mm to 45 lp/mm correspondingly.

     

/

返回文章
返回