Instrument for measuring small angles by use of multiple total internal reflections in heterodyne interferometry

Ming-Hung Chiu; Shinn-Fwu Wang; Rong-Seng Chang

doi:10.1364/ao.43.005438

Instrument for measuring small angles by use of multiple total internal reflections in heterodyne interferometry

Appl Opt. 2004 Oct 10;43(29):5438-42. doi: 10.1364/ao.43.005438.

Authors

Ming-Hung Chiu¹, Shinn-Fwu Wang, Rong-Seng Chang

Affiliation

¹ Department of Electro-Optical Engineering, National Huwei University of Science and Technology, 64 Wunhua Road, Huwei Yunlin 632, Taiwan, China. mhchiu@nhust.edu.tw

PMID: 15508599
DOI: 10.1364/ao.43.005438

Abstract

A new instrument for measuring small angles by use of multiple total internal reflections in heterodyne interferometry is presented. With this instrument we can achieve a small rotation angle only by measuring the variation in phase difference between s- and p-polarization states. To improve its sensitivity we increase the number of total internal reflections by using two parallelogram prisms instead of two right-angle prisms. The angular resolution of the new instrument is better than 2.2 x 10(-6) rad over the measurement range -2.12 degrees < or = theta < or = 2.12 degrees for 20 total-internal reflections. The experimental results and the theoretical curve are in good agreement.