Application of Phase Measurement Deflectometry Method in Transparent High-Reflection Materials

Transparent and high inverse material objects have special physical and optical properties, and are widely used I n many fields such as optics, automotive, aerospace, etc., and it is very important to ensure the surface shape accuracy. As a deflection measurement method based on the principle of vision, phase measurement deflectometry (PMD) is widely used in the measurement of highly reflective surfaces, and has advantages in measuring transparent high reflection materials. However, due to the multi-layer reflective surface of transparent and highly reflective material, the image collected by the traditional PMD method often has the phenomenon of signal aliasing, which will affect the accuracy of measurement. For this reason, we propose a new P method for transparent high inverse materials, and propose a method based on dynamic flat mirror calibration and reflective target calibration for this large field of view measurement system. This measurement method discretized the characteristic fringes, and used a single frame phase resolution method to obtain the phase information, and used a binocular camera to shoot one image respectively to complete the surface shape measurement of the transparent high-inverse material surface, which has the advantages of high measurement accuracy and fast speed, and is suitable for transparent high-inverse materials with uniform thickness and moderate curvature as well as ordinary high-inverse surfaces.

Keywords: Phase measurement deflectometry, Transparent and highly reflective, Surface measurement, System calibration.

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