Based on the phenomena of Brewster's angle and the principles of common-path heterodyne interferometry, we present an optical method for measuring the optical rotation angle and the refractive index of a chiral solution simultaneously in one optical configuration. A heterodyne light beam and a circularly polarized heterodyne light beam are separately guided to project onto the interface of a semicircle glass and a chiral solution. One of the beams is transmitted through the solution, and the other is reflected near Brewster's angle at the interface. Then the two beams pass through polarization components respectively for interference. The phase differences of the two interference signals used to determine the rotation angle and the refractive index become very high with the proper azimuth angles of some polarization components, hence achieving an accurate rotational angle and a refractive index. The feasibility of the measuring method was demonstrated by our experimental results. This method should bear the merits of high accuracy, short sample medium length, and simpler operational endeavor.
© 2007 Optical Society of America
Instrumentation, Measurement, and Metrology
Original Manuscript: August 7, 2007
Manuscript Accepted: October 2, 2007
Published: November 19, 2007
Jiun-You Lin, Kun-Huang Chen, and Jing-Heng Chen, "Optical method for measuring optical rotation angle and refractive index of chiral solution," Appl. Opt. 46, 8134-8139 (2007)