摘要 |
Toric surfaces are mounted on a transparent support plate and measured at grazing incidence using a pair of leading and following diffractive optics for diffracting a test beam with respect to a reference beam. The leading diffractive optic diffracts rays of the test beam through various diffraction angles so that after passing through the transparent support plate, the rays strike the toric surface at a constant grazing angle. The following diffractive optic further diffracts the rays of the test beam through other diffraction angles into realignment with the reference beam.
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