Experimental Investigations of Sigma Vectors in Nodal Aberration Theory for Coma-Free Pivot Misalignment State of a Cassegrain Telescope

Year 2024, Volume: 12 Issue: 4, 1145 - 1154, 31.12.2024

Meltem Yeşiltepe , Sefer Bora Lişesivdin

https://doi.org/10.29109/gujsc.1586470

Abstract

The study aims experimental investigation of the sigma vectors in Nodal Aberration Theory for a customized non-aplanatic high-precision Cassegrain telescope under coma-free pivot point (CFPP) misalignment conditions. Rotating the telescope's secondary mirror at the CFPP introduces a specific misalignment condition, resulting in unchanged coma aberration across the field of view (FOV). Evaluating CFPP misalignment is essential for optical alignment processes. Investigating the field aberration vectors for the telescope’s CFPP misalignment state provides valuable insights into the behavior of field-dependent aberrations and enhances the understanding of CFPP misalignment conditions.

Keywords

Come-free, Misalignment, Telescope

Thanks

The authors would like to thank Dr. Özgür Karcı and Mustafa Ekinci for their support and for the resources they made available. The authors would also like to thank Eray Arpa for his valuable assistance.

References

• [1] Hopkins H. H., (1950), Wave Theory of Aberrations, Clarendon Press.
• [2] Buchroeder R. A., (1976), Tilted Component Optical Systems, Ph.D. Thesis, The University of Arizona, Tucson.
• [3] Shack R. V., and Thompson K., Influence of alignment errors of a telescope system on its aberration field, 251 (1980) 146-53.
• [4] Thompson K. P., Description of the third-order optical aberrations of near-circular pupil optical systems without symmetry, Journal of the Optical Society of America A, 22 (2005) 1389-401.
• [5] Thompson K. P., 'Multinodal fifth-order optical aberrations of optical systems without rotational symmetry: spherical aberration', Journal of the Optical Society of America A, 26, (2009) 1090-100.
• [6] Thompson K. P., 'Multinodal fifth-order optical aberrations of optical systems without rotational symmetry: the comatic aberrations', Journal of the Optical Society of America A, 27, (2010), 1490-504.
• [7] Thompson K. P., Multinodal fifth-order optical aberrations of optical systems without rotational symmetry: the astigmatic aberrations', Journal of the Optical Society of America A, 28 (2011) 821-36.
• [8] Thompson K. P., Schmid T., Cakmakci O., and Rolland J. P., Real-ray-based method for locating individual surface aberration field centers in imaging optical systems without rotational symmetry, Journal of the Optical Society of America A, 26 (2009) 1503-17.
• [9] Schmid, T., Rolland J. P., Rakich A., and Thompson K. P., Separation of the effects of astigmatic figure error from misalignments using Nodal Aberration Theory (NAT), Optics Express, 18 . (2010) 17433-47.
• [10] Fuerschbach, K., Rolland J. P., and Thompson K. P. Theory of aberration fields for general optical systems with freeform surfaces, Optics Express, 22 (2014) 26585-606.
• [11] Zhao N., Papa J. P., Fuerschbach K., Qiao Y., Thompson K. P., and Rolland J. P., Experimental investigation in nodal aberration theory (NAT) with a customized Ritchey-Chrétien system: third-order coma, Optics Express, 26 (2018) 8729-43.
• [12] Karcı Ö., Arpa E., Ekinci M., and Rolland J. P., 2021. Experimental investigation of binodal astigmatism in nodal aberration theory (NAT) with a Cassegrain telescope system, Optics Express, 29 (2021) 19427-40.
• [13] Karcı Ö., A simulation and experimental validation of third-order coma in nodal aberration theory with a Cassegrain telescope', Turkish Journal of Physics, 45 (2021) 378-89.
• [14] Karcı, Ö., Yeşiltepe M., Arpa E., Wu Y., Ekinci M., and Rolland J. P., Experimental investigation in nodal aberration theory (NAT): separation of astigmatic figure error from misalignments in a Cassegrain telescope', Optics Express, 30, (2022) 11150-64.
• [15] Yeşiltepe M., Bauer A., Karcı Ö., and Rolland J. P., Sigma vector calculations in nodal aberration theory and experimental validation using a Cassegrain telescope, Optics Express, 31 (2023) 42373-87.
• [16] Schmid T., (2010). Misalignment induced nodal aberration fields and their use in the alignment of astronomical telescopes, Ph.D. Thesis, University of Central Florida, Orlando.
• [17] Karcı Ö., Ekinci M., Design of a high-precision, 0.5 m aperture Cassegrain collimator, Applied Optics, 59 (2020) 8434-42.