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Creators/Authors contains: "Chaudhuri, Romita"

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  1. ; ; (, Advanced Metrology Systems III: Interferometry at Optica Design and Fabrication)
    A spatial light modulator is deployed as the nulling element in the interferometric measurement of a freeform optic. Form measurement of a 65 mm aperture concave freeform with 91 μm peak-valley freeform sag is reported. 
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  2. ; ; ; (, Optics Express)
    We report the implementation of an interferometric null test using a high-definition spatial light modulator (SLM) as a reconfigurable alternative to a computer-generated hologram. We detail the alignment process chain, including novel techniques using the SLM to project alignment fiducials on the test part. To validate the alignment protocol, we measure a mild off-axis conic with the SLM-based system and cross-validate with conventional interferometry within 30 nm root-mean-square (RMS) surface figure. Finally, we report the null test of a 65 mm clear aperture concave freeform with 91 μm peak-valley sag departure from the base sphere. The measured surface figure of the freeform is within 40 nm RMS compared to the measurement with a commercial metrology instrument. 
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  3. ; ; (, Optics Express)