Co-focus experiment of segmented mirror

Li Bin^{1, 2, 3, †}, Yu Wen-Hao^{1, 2, 3}, Chen Mo^{1, 2, 3}, Tang Jin-Long^{1, 3}, Xian Hao^{1, 3, ‡}

(color online) (a) Interference fringes when the calibration light beam has a tilt error; (b) the interference fringes when the segmented mirror has fine co-focus.