Refractive Index Determination in Fuel Cells by using Laser Heterodyne Interferometer

In this paper, we present the inrferometry method for refractive index determination in membrane of fuel cells. This technique is based on the use of an improved laser heterodyne interfeometer. The photocurrents of the avalanche photodiodes resulting from reflected beams of optical head is led to the signal conditioner and digital signal processing sections. The optical path difference between the target and reference paths is fixed, and as a result, the phase shift is calculated in terms of the refractive index.

Keywords:

interferometer , fuel cell , membrane , laser , heterodyne , refractive index