Cao Y Z, Ma W L. Application of two step sensitivity matrix method in Cassegrain telescope alignment[J]. Opto-Electron Eng, 2020, 47(2): 180536. doi: 10.12086/oee.2020.180536
Citation: Cao Y Z, Ma W L. Application of two step sensitivity matrix method in Cassegrain telescope alignment[J]. Opto-Electron Eng, 2020, 47(2): 180536. doi: 10.12086/oee.2020.180536

Application of two step sensitivity matrix method in Cassegrain telescope alignment

More Information
  • In order to adjust the position of the secondary mirror of Cassegrain telescope with large field of view, a computer aided adjustment method of two-step sensitivity matrix model was proposed. Based on the analysis of the shortcomings of the traditional sensitivity matrix method of the two order model, a fine tuning step was added based on the characteristics of the sensitivity matrix and the traditional sensitivity matrix method was improved. For the Cassegrain system, the relationship between the Zernike coefficients and the misalignment was analyzed, and the calibration simulation of Cassegrain system with 300 mm aperture and 0.6° field of view was carried out. The simulation results show that after correction by traditional sensitivity matrix method, the mean values of offset along x, y, z axes and tilt around x, y axes are -0.0684 mm, -0.0892 mm, 0.0015 mm, 0.0498° and -0.0444°, respectively, and the full field wavefront aberration RMS is less than 0.1λ(λ=632.8 nm). After correction by two step sensitivity matrix correction method, the mean values are -0.0018 mm, -0.0012 mm, 0.0002 mm, 0.0008° and -0.0012°, respectively, and the full field wavefront aberration RMS is less than 0.03λ, which is obviously superior to the traditional sensitivity matrix method.
  • 加载中
  • [1] 周龙峰.大口径反射式望远镜在线调整技术研究[D].成都: 中国科学院研究生院(光电技术研究所), 2016.

    Google Scholar

    Zhou L F. Study on the alignment technique of large aperture reflecting telescope on-line[D]. Chengdu: University of Chinese Academy of Sciences (Institute of Optics and Electronics), 2016.http://ir.ioe.ac.cn/handle/181551/7990

    Google Scholar

    [2] Figoski J W, Shrode T E, Moore G F. Computer-aided alignment of a wide-field, three-mirror, unobscured, high-resolution sensor[J]. Proceedings of SPIE, 1989, 1049: 166. doi: 10.1117/12.951421

    CrossRef Google Scholar

    [3] Egdall I M. Manufacture of a three-mirror wide-field optical system[J]. Optical Engineering, 1985, 24(2): 242285. doi: 10.1117/12.7973470

    CrossRef Google Scholar

    [4] 巩盾, 田铁印, 王红.利用Zernike系数对离轴三反射系统进行计算机辅助装调[J].光学精密工程, 2010, 18(8): 1754–1759.

    Google Scholar

    Gong D, Tian T Y, Wang H. Computer-aided alignment of off-axis three-mirror system by using Zernike coefficients[J]. Optics and Precision Engineering, 2010, 18(8): 1754–1759.

    Google Scholar

    [5] 杨晓飞.三反射镜光学系统的计算机辅助装调技术研究[D].长春: 中国科学院长春光学精密机械与物理研究所, 2005.

    Google Scholar

    Yang X F. Study on the computer-aided alignment of three-mirror optical system[D]. Changchun: Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 2005.

    Google Scholar

    [6] Kim S, Yang H S, Lee Y W, et al. Merit function regression method for efficient alignment control of two-mirror optical systems.[J]. Optics Express, 2007, 15(8): 5059–5068. doi: 10.1364/OE.15.005059

    CrossRef Google Scholar

    [7] 王彬, 蒋世磊.卡塞格林系统计算机辅助装调技术研究[J].光学仪器, 2008, 30(1): 50–54. doi: 10.3969/j.issn.1005-5630.2008.01.011

    CrossRef Google Scholar

    Wang B, Jiang S L. Study on computer-aided alignment method of Cassegrain system[J]. Optical Instruments, 2008, 30(1): 50–54. doi: 10.3969/j.issn.1005-5630.2008.01.011

    CrossRef Google Scholar

    [8] 孙敬伟, 吕天宇, 姚丽双, 等.发射望远镜的设计与装调[J].光学精密工程, 2014, 22(2): 369–375.

    Google Scholar

    Sun J W, Lv T Y, Yao L S, et al. Design and assembly of transmitter-telescope[J]. Optics and Precision Engineering, 2014, 22(2): 369–375.

    Google Scholar

    [9] 张向明, 姜峰, 孔龙阳, 等.卡塞格林系统光学装调技术研究[J].应用光学, 2015, 36(4): 526–530.

    Google Scholar

    Zhang X M, Jiang F, Kong L Y, et al. Research on optical alignment technology for Cassegrain system[J]. Journal of Applied Optics, 2015, 36(4): 526–530.

    Google Scholar

    [10] 顾志远, 颜昌翔, 李晓冰, 等.改进的灵敏度矩阵法在离轴望远镜装调中的应用[J].光学精密工程, 2015, 23(9): 2595–2604.

    Google Scholar

    Gu Z Y, Yan C X, Li X B, et al. Application of modified sensitivity matrix method in alignment of off-axis telescope[J]. Optics and Precision Engineering, 2015, 23(9): 2595–2604.

    Google Scholar

  • Overview: With the development of telescope technology, the aperture and field of view of telescope are becoming larger and larger, the structure of optical system is becoming more and more complex, and the difficulty of fabrication and assembly is also increasing. The speckle pattern of the focal plane of the optical system can be measured by interferometer and other testing equipment, and the Zernike coefficients can be calculated by the speckle pattern. For Cassegrain telescope, in order to obtain good imaging quality, it is necessary to correct the position of its secondary mirror. By using computer-aided alignment technology, the optical system can be real-time detected and compared with the theoretical results. By establishing a mathematical model between Zernike coefficient and misalignment, the misalignment of the components can be corrected accurately. The most widely used computer-aided alignment method is the sensitivity matrix method. Sensitivity matrix method is a method of correcting aberration by establishing mathematical model of misalignment and Zernike coefficient on the basis of analyzing aberration characteristics. The traditional sensitivity matrix method only carries out single correction. According to the meaning of Zernike coefficient, z3z4z5z6z7 and z8 are chosen to construct the sensitivity matrix. Based on the analysis of the shortcomings of the traditional sensitivity matrix method of the two order model, a fine tuning step was added based on the characteristics of the sensitivity matrix. The calculation method of sensitivity is improved. According to the relationship between misalignment and Zernike coefficient, the selection principle of Zernike coefficient for constructing sensitivity matrix is proposed. The traditional sensitivity matrix method is improved. For the Cassegrain system, the relationship between the Zernike coefficients and the misadjustment was analyzed, and the calibration simulation of Cassegrain system with 300 mm aperture and 0.6° field of view was carried out. The simulation results show that after correction by traditional sensitivity matrix method, the mean values of offset along x, y, z axes and tilt around x, y axes are -0.0684 mm, -0.0892 mm, 0.0015 mm, 0.0498° and -0.0444°, respectively, and the full field wavefront aberration RMS is less than 0.1λ (λ=632.8 nm). After correction by two step sensitivity matrix correction method, the mean values are -0.0018 mm, -0.0012 mm, 0.0002 mm, 0.0008° and -0.0012°, respectively, and the full field wavefront aberration RMS is less than 0.03λ. The corrected optical system reaches the diffraction limit and approaches the design position, which is obviously superior to the traditional sensitivity matrix method.

  • 加载中
通讯作者: 陈斌, bchen63@163.com
  • 1. 

    沈阳化工大学材料科学与工程学院 沈阳 110142

  1. 本站搜索
  2. 百度学术搜索
  3. 万方数据库搜索
  4. CNKI搜索

Figures(2)

Tables(8)

Article Metrics

Article views(6432) PDF downloads(1951) Cited by(0)

Access History

Other Articles By Authors

Article Contents

Catalog

    /

    DownLoad:  Full-Size Img  PowerPoint