Phase geographical map for determining the material type of a right-angle prism
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Published on: May 20, 2013
Ming-Hung Chiu1, Chih-Wen Lai, Shinn-Fwu Wang
1Department of Electro-Optical Engineering, National Formosa University, Huwei, Yunlin, Taiwan. mhchiu@nfu.edu.tw
Abstract:
A phase geographical map for determining a right-angle prism is presented. The proposed method is based on total-internal-reflection effects and chromatic dispersion. Under the total-internal-reflection condition, the phase difference between the S and P polarizations, as a function of the wavelength and refractive index, can be extracted and measured using heterodyne interferometry. Various wavelengths correspond to various refractive index values. The proposed map is convenient in ensuring the prism material using a specific V number. The method has the following merits: high stability, ease of operation, and rapid measurement.
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