Proceedings PaperMisalignments in phased-array telescopes: description and correction
|Format||Member Price||Non-Member Price|
Designs for phased-array imaging telescopes covering a wide field of view (0.25 degrees) with satisfaction of all optical phasing conditions have been developed. Important concerns regarding the implementation of these telescopes include misalignment types and tolerances, and the complexity of active alignment systems needed to correct the misalignments. In this paper a phased-array telescope point design is briefly described. Possible misalignments in the array configuration are defined, and functional forms are given. A technique is introduced for including array misalignments in the wavefront aberration polynomial used to describe image quality in the final array focal plane. This polynomial is then used to show to what extent the misalignment-induced subtelescope aberrations defocus and coma may be corrected using only adjustments in the array configuration. Application to the point design shows that defocus and coma may be corrected, by the addition of piston and tilt terms, by factors equal to the ratio between the Seidel aberration coefficient and the corresponding Zernike polynomial coefficient. It is shown that correction possibilities result in looser subtelescope alignment tolerances and in the simplification of active alignment systems for individual subtelescopes.