Method for accurate measurement of wideband transmittance of thin-film coatings at large angle of incidence

Yongli Liu; Jinlong Zhang; Xinbin Cheng; Zhanshan Wang

doi:10.1364/AO.52.000226

Method for accurate measurement of wideband transmittance of thin-film coatings at large angle of incidence

Appl Opt. 2013 Jan 10;52(2):226-30. doi: 10.1364/AO.52.000226.

Authors

Yongli Liu¹, Jinlong Zhang, Xinbin Cheng, Zhanshan Wang

Affiliation

¹ Institute of Precision Optical Engineering, Department of Physics, Tongji University, Shanghai 200092, China.

PMID: 23314639
DOI: 10.1364/AO.52.000226

Abstract

Accurate directional transmittance can reduce uncertainty in parameters regression of optical thin-films. When directional transmittance is measured at large angle of incidence (AOI), a polarizer has to be used to produce linearly polarized light and it also becomes an error source. This study presents a method for accurate measurement of wideband transmittance at large AOI, which is aimed to eliminate the polarization error in measured transmittance at oblique incidence. Using this method, we can measure the directional transmittance with a good precision if a partially polarized incident beam is provided. This method reduces the requirement for the performance of the polarizer, and will find application in the highly integrated spectrophotometers.