A method based on the digital holographic microscopy (DHM) for measuring the refractive index of photopolymer is proposed. The digital hologram is recorded by the Mach-Zehnder off-axis interference system. The high-precision phase distribution is extracted by the hybrid reconstruction algorithm. Combining the profile distribution measured by optical profilometer, the refractive index of photopolymer is obtained by image registration. The evolution of refractive index of photopolymer during the UV curing process is quantitatively analyzed. The dynamic phase distribution of photopolymer is measured by DHM, and then the dynamic refractive index distribution is obtained. The relationship between the average refractive index and exposure time is plotted. The proposed method can be used to reveal the optical performance of microscopic optical devices and design high-quality optical systems.
LI Weixia, HUANG Sujuan, YAN Cheng, XIA Shengli, YIN Weihao
. Refractive Index Measurement of Photopolymer Based on Digital Holographic Microscopy[J]. Journal of Applied Sciences, 2022
, 40(2)
: 179
-189
.
DOI: 10.3969/j.issn.0255-8297.2022.02.001
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