2026-09-20T15:24:23Zhttps://dspace.mit.edu/server/oai/requestoai:dspace.mit.edu:1721.1/785432022-01-13T07:54:07Zcom_1721.1_7582com_1721.1_7581col_1721.1_131024
Paul L. Schechter.
Janish, Ryan J. (Ryan Joseph)
Massachusetts Institute of Technology. Department of Physics.
Massachusetts Institute of Technology. Department of Physics
2013-04-12T19:37:48Z
2013-04-12T19:37:48Z
2012
2012
http://hdl.handle.net/1721.1/78543
836817391
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 57).
In this thesis, I present a new technique for measuring the optical aberrations produced by a telescope, with an eye towards future use of these aberration measurements to align wide-field telescopes. This method determines the aberrations by simultaneously fitting a pair of oppositely defocused images to a mostly analytic model. I develop the model and describe its software implementation in detail, and then report on the results of tests with simulated and real data. This technique is able to extract the aberrations from simulated data rapidly and accurately, and it has been used with mixed success to analyze data from the VISTA telescope. With the VISTA data, the algorithm is unable to match small-scale brightness variations in the images. However, it was able to determine aberrations with median accuracies of 0.08 um for coma, 0.08 um for astigmatism, 0.9 um for tilt, and 0.3 um for defocus. It was also quite fast, with an average of 34 iterations until convergence.
by Ryan J. Janish.
S.B.
57 p.
eng
Massachusetts Institute of Technology
M.I.T. theses are protected by
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http://dspace.mit.edu/handle/1721.1/7582
Physics.
An algorithm for rapid measurement of aberrations in pairs of out-of-focus images
Thesis
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