Improved performance of three mirror anastigmat telescope with freeform surface: Optical design, testing and validation aspects

被引：0
作者：
B, Vishweshwar Rao [1 ,2 ]
K V, Sriram [2 ]
C.S, Narayanamurthy [1 ]
机构：
[1] Department of Physics, Indian Institute of Space Science and Technology, Valiamala (PO), Kerala, Thiruvananthapuram
[2] Laboratory for Electro-Optics System, Peenya Industrial Estate, Karnataka, Bengaluru
来源：
Optik | 2024年 / 314卷
关键词：
Convex freeform surface; Fringe Zernike; Interferometry; MTF; PSF; Strehl Ratio; Three-mirror-anastigmat;
D O I：
10.1016/j.ijleo.2024.171998
中图分类号：
学科分类号：
摘要：
“In this paper, the optical design of a Three Mirror Anastigmat (TMA) Telescope is modified by substitution of a convex freeform secondary and optimization carried out to obtain improved performance. The proposed convex freeform surface is precisely manufactured using the bonnet polishing technique and tested with a sub-aperture stitched algorithm, meeting the specified surface accuracy requirements. Further, to validate the design, the realized secondary freeform optic is tested in conjunction with primary and tertiary optics in the conceived TMA configuration. The telescope system performance is established using a double-pass interferometric test setup. The modified design enhances the telescope system's performance in the extended field of view (FoV) from ±2.5° to ±3.5° across the track and from ±0.4° to ±0.6° along the track. Measured performance results demonstrate an average modulation transfer function (MTF) of 0.56 and an average Strehl ratio of 0.64 at all field points. The effective focal length of the system is computed to be 975 mm. In summary, the proposed freeform surface significantly improves the optical system performance within the available real estate of the envisaged space telescope system.” © 2024 Elsevier GmbH
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共 23 条
  • [1] Smith, Warren J., Modern Optical Engineering: The Design of Optical Systems, (2008)
  • [2] Wilson, Raymond N., Reflecting Telescope Optics I: Basic Design Theory and Its Historical Development, (2013)
  • [3] Korsch D., Closed Form Solution for Three-Mirror Telescopes, Corrected for Spherical Aberration, Coma, Astigmatism, and Field Curvature, Appl. Opt., 11, pp. 2986-2987, (1972)
  • [4] Kevin P.T., Pablo B., Jannick P.R., Freeform optical surfaces: report from osa's first incubator meeting, Opt. Photonics N., 23, 9, pp. 32-37, (2012)
  • [5] Nakano T., Tamagawa Y., Configuration of an off-axis three-mirror system focused on compactness and brightness, Appl. Opt., 44, pp. 776-783, (2005)
  • [6] Tohme Y.E., Lowe J.A., (2004)
  • [7] Aaron B., Schiesser E.M., Rolland J.P., Concurrent engineering of a next-generation freeform telescope: optical design, Advanced Optics for Imaging Applications: UV through LWIR IV, 10998, (2019)
  • [8] 11852, pp. 141-153, (2021)
  • [9] Duveau L., Freslier C., Druart G., Lepine T., Freeform TMA without planar symmetry for compact catoptric imaging system, Results Opt., 12, (2023)
  • [10] Braunecker B., Hentschel R., Tiziani H.J., (2008)
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