Table 10.

Interferometer pixel-to-pixel spacing requirements^a

Magnification, ×	Pixel-to-pixel spacing, μm
5	< 1.57
10	< 0.83
20	< 0.39
40	< 0.21
80	< 0.11

^aThis table does not include magnifications at or less than 2.5 × for optical interferometry because the pixel-to-pixel spacings will be too large for this work and the possible introduction of a second set of interferometric fringes in the data set at these magnifications can adversely affect the data. Therefore, magnifications at or less than 2.5 × shall not be used with optical interferometry.