spatial resolution. Combined with the precision in reading the turn dial position, which is Dk d 3:3lm 61 unit, we obtain a final resolution of Dx ¼ 83l m or ¼ cosb ¼ 0:9659 ¼ 8:37nm=mm: (4) Dk ¼0.65nm, respectively. This level of resolution is, of Dx f 381mm course, undesirable for a research-grade setup
