Scanning Optical Head with Nontilted Reference Beam: Assuring Nanoradian Accuracy for a New Generation Surface Profiler in the Large-Slope Testing Range

<table>LTP III slope error produced by tilted reference. (a) Reference beam’s spot is tilted in 1.5 mrad. (b) Nontilted reference beam at the center of the CCD.  (c) Slope error caused by tilted reference.</table>

International Journal of Optics

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Figure 3

Figure 3: Scanning Optical Head with Nontilted Reference Beam: Assuring Nanoradian Accuracy for a New Generation Surface Profiler in the Large-Slope Testing Range 

Figure 3 | Scanning Optical Head with Nontilted Reference Beam: Assuring Nanoradian Accuracy for a New Generation Surface Profiler in the Large-Slope Testing Range 