In order to address the variance in the focal lengths of the segments for the Deutsches Grossteleskop (DGT), a method is delineated to calculate permissible focal tolerances. Sets of arbitrarily distributed delta-f (differences in focal lengths), where for each the average is zero and the standard deviation is normalized to 1 mm, are used to calculate the permissible tolerance. The DGT's correlation function provides the criteria for the analysis, and the results demonstrate that the two types of segmentation considered should have a delta-f of 0.072 for the four-quadrant configuration and of 0.360 for the 13-piece configuration.

Date Published: 1 August 1990
PDF: 5 pages
Proc. SPIE 1271, Adaptive Optics and Optical Structures, (1 August 1990); doi: 10.1117/12.20416

Published in SPIE Proceedings Vol. 1271:
Adaptive Optics and Optical Structures
Joachim J. Schulte-in-den-Baeumen; Robert K. Tyson, Editor(s)