Characterization of a phase modulator or phase shifter has always been an integral part of phase-modulating or phase-adjusting applications. We propose a simplified approach to characterize a phase modulator by investigating the performance of phase shifts from grabbed interferograms using the phase extraction method. After reviewing some phase analysis techniques, the interframe intensity correlation (IIC) matrix method is introduced to the investigation. The proposed strategy is illustrated by the measurement of a free-space electro-optic modulator (EOM). Placing the modulator in one arm of a Michelson interferometer, the global phase shifts are estimated by the IIC method from the phase-stepped interferograms. Experimental results demonstrate the tested EOM has a phase modulation response of at least 2 pi rad with a pi/20 rad modulation precision for lambda = 1064 nm. In addition, our method is applicable to various types of phase modulator or phase shifter calibration, e.g., electro-optic phase modulator, spatial light modulator, or piezoelectric transducer (PZT). (C) 2012 Optical Society of America
1.Univ Elect Sci & Technol China, Sch Optoelect Informat, Chengdu 610054, Peoples R China 2.Chinese Acad Sci, Inst Opt & Elect, Chengdu 610209, Peoples R China
Yue, Huimin,Song, Lei,Hu, Zexiong,et al. Characterization of the phase modulation property of a free-space electro-optic modulator by interframe intensity correlation matrix[J]. APPLIED OPTICS,2012,51(19):4457-4462.