Measurement of refractive index and thickness of transparent plate by dual-wavelength interference.
We developed an accurate and efficient method for measuring the refractive indices of a transparent plate by analyzing the transmitted intensity versus angle of incidence. By using two different wavelengths, we resolved the 2pi-ambiguity inherent to the phase measurement involving a thick medium, leading to independent determination of the absolute index of refraction and the thickness with a relative uncertainty of 10(-5). The validity and the accuracy of our method were confirmed with a standard reference material. Furthermore, our method is insensitive to environmental perturbations, and simple to implement, compared to the conventional index measurement methods providing similar accuracy.
Choi
Hee Joo
HJ
Department of Physics, Pusan National University Busan 609-735, Korea.
Lim
Hwan Hong
HH
Moon
Han Seb
HS
Eom
Tae Bong
TB
Ju
Jung Jin
JJ
Cha
Myoungsik
M