Summary: | 碩士 === 國立聯合大學 === 光電工程學系碩士班 === 107 === In this work, we present a dynamic Stokes parameter imaging system with dual-wavelength technique. First, the reference signal of the photo-elastic modulator (PEM) in polarization state analyzer(PSA) is used by the pulse delay generator to obtain stroboscopic illumination for two laser diodes. The two laser beams and a polarization state generator (PSG), which consists of a polarizer, are used to generate a beam of polarized light. Four specific time phases of the PEM are located. Equivalent phase difference modulation technique allows dual wavelength measurement by simply adjusting the time phase parameter rather than PEM controller wavelength setting. Charge coupled devices (CCDs) are used to document the four two-dimensional-intensity images, and MatLab is used to calculate the Stokes parameter distribution chart. Finally, LabView is used to perform fully automatic dual wavelength dynamic measurement of polarization distribution variation due to time and temperature.
Keywords: Dual-wavelength, Photo-elastic modulator, Stroboscopic illumination, Equivalent phase difference modulation, Automated measurement, Dynamic sample measurement, Stokes parameters.
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