Imperfections of Scalar Approximation in Calibration of Computer-Generated Holograms for Optical Surface Measurements
نویسندگان
چکیده
Computer-generated hologram (CGH) null correctors are used as accuracy standards for interferometric measurements of optical surfaces and systems. Diffractive optics calibrators (DOCs) have been developed to evaluate the phase tolerance CGHs based on scalar approximation by measuring variations in duty cycle etching depth. However, if grating period a CGH < 5λ, is not accurate analysis reconstruction. In this study, measurement errors DOCs with small-period were investigated experimentally verified. Results show that imperfections cannot be ignored development rigorous evaluation methods improve great practical significance.
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ژورنال
عنوان ژورنال: Applied sciences
سال: 2021
ISSN: ['2076-3417']
DOI: https://doi.org/10.3390/app11156897