Surface Measurement by Digital Holography with New Unwrapping Method

Abstract:

Digital holography can record 3-D image of the object by using one CCD camera. Surface shape can be measured by changing angles of the object-illuminating mirror. But the measured signals are wrapped because of the periodicity of a sinusoidal function, and then phase unwrapping is needed. We have developed a new modified phase unwrapping method and applied it to surface measurement. Unwrapping errors were significantly reduced in comparison to application of the previous method.

• Periodical: Key Engineering Materials (Volume 643)
• Pages: 179-183
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.643.179
• Online since: May 2015
• Authors: Yoshitaka Takahashi*, Fuyuki Sahara
• Keywords: Holography, Image Processing, Interferometry, Optical Measurement

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