Research On The Measurement Of Birefringence By Senamont

A method based on Senamont method was proposed to precisely measure the stress birefringence of optical crystal. Using the theory of polarized light and Jones matrix, the analytic expressions for measurement error of optical path difference caused by the rotating positional accuracy of the analyzer, the phase deviation of the quarter wave plate and the azimuth error of specimens under test were derived respectively. The results of error analysis indicate that the measurement error of optical path difference caused by the rotating positional accuracy of the analyzer is the largest.In this paper,by analyzing the principle of Senamont,a method in the way of comparison aiming at measuring the birefringence of infrared crystals was given in theory, and the practicable testing process including the least error sources was discussed,with signal intensity in each step given by its algebraic expression.The design of testing and controlling system and the application software by Labview of this equipment were studied in detail,signal real-time sampled and ransformed,devices accurately positioned according to the measured intensity and the testing process monitored by the way of real-time result displayed on the computer in the form of both data and curve. As last,the precision analysis was given on the base of analyzing errors induced by various devices through the testing pass.The proposed measurement system can measure a variety of wave plates,and have the advantage of simple operation,the cycle is short and high precision. weanalyzedthe error sources of thetest system and verified the reasonableness of the program.