| Polarization is one of the basic properties of light and is used to describe the direction of the oscillating electrical vector,showing another form of information that is different from the intensity and frequency of light.The detection of polarized information of light not only reveals the different polarization properties of light,but also reflects and reveals the properties of polarization sensitive materials and media.The polarization of light is inherently sensitive to optical anisotropy and reflects the local order of the structure,which can be used to reveal the intrinsic structure and composition of the material,as well as the essential properties of scattering,emission and absorption.Polarization is also an important parameter for describing the interaction of light and matter in wave engineering,nanometer processing grade biomedical engineering.In addition,the measurement of the parameters reflecting the polarization response of the material is of great significance for revealing the internal structure or birefringence properties of the material,characterizing the complex modulation properties of the optical device,and finding the physical mechanism of the interaction between light and matter.The traditional intensity-based sensor can not detect the polarization information of the light.For the inherent vector characteristics of the polarization,it is usually necessary to make multiple measurements on the same polarization information,one for each vector component.Therefore,the measurement of the polarization information of the light is complicated with respect to the frequency and intensity,and it is more difficult to measure the polarization characteristics of the polarization sensitive materials and devices.At present,the efficient and accurate measurement of the polarization characteristics of these materials and devices is still an urgent problem problem.In this paper,the theoretical and experimental research on the holographic polarization measurement and imaging method of polarized sensitive materials and devices are as follows: 1.Methods of measuring the polarization characteristics of polarized sensitive materials are1.Methods of measuring the polarization characteristics of polarized sensitive materials are reviewed.The measurement of polarization characteristics is described in terms of the two descriptive forms(Stokes-Mueller and Jones formlism).For Jones matrix measurements,the measurement method is divided into intensity-based measurements,based on intensity and phase measurements and digital holography-based measurement methods,and some typical measurement schemes are described,respectively.For the measurement of Miller matrix,three kinds of measurement methods based on rotating optical element method,photoelastic modulator method and liquid crystal variable retarder are introduced.2.The basic theory of polarization and the description of polarization characteristics of polarization-sensitive media are reviewed.The basic theory of polarized light and the matrix description form of two kinds of polarized light are introduced,and the matrix form and operation method of the polarization device are also described.For the content of the study,the description of the general polarization sensitive medium is summarized,including the use of Jones matrix and Miller matrix formlism,and the connection and difference between the two methods are compared.3.The theoretical analysis and simulation of off-axis Fresnel holography under point source illumination are carried out.The analysis of the object wave item in the holographic record formula show that the object wave item of the off-axis Fresnel hologram is equal to the Fresnel diffraction of an amplified object under the point source illumination,and the formula of the diffraction distance is given.The frequency shift of the holographic object wave term and the conjugate term is obtained by theoretical analysis.And the influence of the distances between the two point sources,the point source plane and the object plane,and the object plane and the recording surface on hologram reconstruction is discussed by simulation.4.A method and measurement system of four-channel polarization holography based on orthogonal grating and angular multiplexing are proposed.By using the orthogonal grating combined with the angular multiplexing technique,a four-channel polarization holography method is realized,and all the four complex parameters of the Jones matrix of the polarization sensitive medium can be obtained by one measurement.The method is theoretically analyzed,and the concrete steps and formula description for are described by using the four-channel hologram to retrieve the Jonse matrix parameters of polarization sensitive medium.The feasibility of the method is verified by computer programming.The experimental system is established,and the Jones matrix of the spatially-varying retardation plate is measured.Based on the measured 2-D Jones matrix,the polarization response of the incident light is simulated and the results are consistent with the experimental results.5.A fiber-based and lensless holography measurement and imaging system based on single mode fiber is proposed.In this system,a multi-source lensless off-axis Fresnel holographic recording geometry is adopted,and two optical fiber splitters are used to generate the multiple reference and illumination beams required for recording a four-channel angular-multiplexing polarization hologram(AMPH).Using this system and the method described in this paper,spatially resolved Jones matrix parameters of a polarization-sensitive material can be retrieved from one single-shot AMPH.the feasibility of the method is demonstrated by extracting a 2-D Jones matrix of a composite polarizer.Applications of the method to measure the Jones matrix maps of a stressed polymethyl methacrylate sample and a mica fragment are also presented.Benefit from the fiber-based and lensless off-axis holographic design,the system possesses a quite compact configuration,which provides a feasible approach for development of an integrated and portable system to measure Jones matrix parameters of polarization-sensitive materials.Based on the measured spatially resolved Jones matrix,the phase maps of the two eigenvalues and the phase retardation map between the two eigenvector directions are given.6.The complex parameters of Jones matrix of the twisted nematic liquid crystal spatial light modulator(TN-LCSLM)at full gray level are measured.A method of one-step measurement of the 2-D Jones matrix of the TN-LCSLM is proposed by using dual-source off-axis Frenel holography with angular multiplexing.Firstly,the system noise and phase wrapping in off-axis holography are analyzed.Then the influence of different voltage states of TN-LCSLM on Jones matrix measurement is analyzed theoretically,and the method of eliminating TN-LCSLM off-background noise is proposed and the detailed theoretical analysis is carried out.Finally,the two-dimensional spatial-resolved Jones matrix of TN-LCSLM at 0-255 gray scale is obtained by experiments.The normalized amplitude and phase of each Jones matrix parameter at different gray levels are given. |
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