Diffractive errors in segmented adaptive optics

Segmentation of the primary mirror offers an inexpensive method to produce large, active telescopes or beam directors. We discuss the goal of segment control and our analytic solution configuration functional. We show that the nature of the segmentation, control, and solution generates an additional source of diffractive errors that must be accounted for in the design of these systems. These diffractive errors and not r0 ultimately set the segment size.