In order to optimize the measuring methods of waveplate retardation and determine the discrepancy in experimental results from different measuring methods and instruments

a high-precision multifunctional experimental system was established to measure the waveplate retardation in different measuring methods and to make a comparison with these methods.A comparative experiment of scanning spectrum method

Soleil compensator method and two light intensity measuring methods was carried out. Combined with the experimental results

the errors of these methods were analyzed. The results show that the scanning spectrum method is appropriate for measuring λ/2 waveplate with error less than 0.032%

whose measurement accuracy is mainly determined by the accuracy of monochromator; The error of Soleil compensator method is less than 0.18%

which primarily comes from the accuracy of Soleil compensator

and for the measurement of λ/2 waveplate

scanning spectrum method and Soleil compensator method can verify each other within the error limits; The error of the light intensity measuring methods is related to the sample waveplate retardation

defects of optical path arrangement

polarizers and the defects from measuring methods.