Refractive index measurement using a standard compensating method

Abstract

The first three significant digits of a sample's refractive index are compensated by a standard, therefore a precise measurement, which is the same as the refractive index of the standard, can be obtained. The method only needs a thin sample.

Letter refractive index variation measurements of fluids using common-path Zeeman interferometry

“…Figure 2 shows the sensitivity measurements of the common-path This sensitivity is very high for the refractive index variation measurements of the liquids. Our results indicate that the Zeeman interferometry technique is over 100 times better resolution than the other interferometry techniques in [6] and [7]. T h e sensitivity of the common-path Zeeman interferometry, An = 9.4 x lop9, is about eight times the theoretical resolution limit (An = 1.2 x mainly owing to the cross-talk between the two orthogonally polarized beams, local temperature variation, vibration of the laboratory floor, acoustic noise, electric noise, and so on.…”

“…Optical techniques are in general ideal for the study of the solution properties because they do not perceptibly affect the solution being studied during crystal growth experiments. Several interferometry techniques have been developed to measure the refractive index of liquids and optical materials [l, 21. T h e refractive indices of liquid solutions have been measured to an accuracy of 0.0002 using the angle-of-minimum-deviation technique [3-51. Mach-Zehnder interferometry was used to measure the difference in refractive indices [6] to an accuracy of about lop6. T h e birefrigence of a thin sample was measured to an accuracy of about lop6 using the self-compensation method [7].…”