Refractive Index Measurements Of Lithium Niobate Integrated Optical Substrates By Total Internal Reflection

Abstract

The measurement of the refractive index of lithium niobate integrated optical substrates of various stoichiometries is difficult because of their thinness (til mm). We use a prism coupling method and calculate the refractive index from the angle at which the intensity of the light from the total internal reflection in the prism base drops. The equipment is computer controlled.In addition, the method can be used to analyze lithium niobate boules to ascertain if they are potentially useful for substrates.