Figure 6
Tilt fringes showing resulting alignment of the blank mirror (a) and the installed diffraction gratings (b) and (c). The patterns are obtained by placing the above-mentioned optical elements (diffraction gratings, blank mirror) in the 90° orientation, to provide back-reflection on M1. The identical tilt of the fringes and their equal periods confirm their proper alignment with respect to each other and to the mirror M1. |