(color online) The far field diffraction pattern of the 170-mm hollow CCR with the dihedral angle offsets of 0.10 arc-second, 0.30 arc-second, and 0.24 arc-second. The red lines show the off-centered location of 0.7 arc-second (3.5 μrad) and 1.4 arc-second (7 μrad), which are the intervals of the velocity aberration for LLR.