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Optical Path Difference Measurement Techniques for SLMs



Patrick J. Grother, D P. Casasent


A simple measurement method to obtain 2-D spatial point-by-point optical path difference (OPD) data for spatial light modulators (SLMs) is described. A simple imaging system is used that allows measurements of all SLM parameters on the same laboratory systems. Simple digital processing of the output image for a uniform applied input voltage provides OPD data. Simple methods to confirm amplitude-mostly SLM operations are also provided. Results are presented for Kopin and CRL liquid crystal SLMs.PACS Classification codes - 42.79, 42.62, 42.87/
Optics Communications


liquid crystals, optical path difference, spatial light modulators


Grother, P. and Casasent, D. (2001), Optical Path Difference Measurement Techniques for SLMs, Optics Communications (Accessed July 23, 2024)


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Created March 1, 2001, Updated February 19, 2017