Far Field Inversion Theory And Method For Indirect Icroscopic Imaging Based On Polarization-modulated

How to break the conventional optical diffraction limit and improve the resolution of images is the research hotspot and development direction in modern optical super-resolution microscopic imaging.Totally different from conventional direct imaging,indirect imaging is a measuring method which modulates and measures optical wave vectors,such as polarization status,phase,orientation of the optical path in far field.Then,according to coupling,far field transmission and physical principle inverse near-field optical wave parameters variations.Finally,using parameter variations to characterize anisotropic structural variations and form multi-dimension indirect images.compared with conventional optical microscopy imaging,polarization parameters indirect imaging not only can improve the resolution,measuring efficiency,but also can achieve the complementation of multi-information and lossless to the living organisms.In the thsis,firstly,we introduced electromagnetic theory of light and micro-material structure of near field polarization coupling principle and analyzed the effect of point spread function(PSF)on the resolution of indirect imaging system.And hence,it was proved the effect of phase difference and polarization on PSF by using calcite test.This method analyzes indirectly optical wave vector parameters which are obtained from modulated unit,and hence get wide-field microscopic imaging.Specifically,optical wave vectors are determined by structural anisotropy of the samples.By fitting the variation of intensity,the ray tracing produces the PSF,and hence filtering out those spatial pixels which are smaller than the setting value,and hence inversion imaging.Finally,the PSF is narrowed,the diffraction limit is beaten and a super resolution is achieved.It provides theoretical basis of indirect microscopic imaging inversion.Secondly,it studied the algorithm of optical polarization parameter indirect microscopic imaging by analyzing the relation between structure anisotropy and optical vectors.Due to the distinctions of samples,distinguish its physical model,such as linear birefringence model,dual-absorption model,rotation polarization model or rotation birefringence model.According to different models,different experiment was built and calculated with different equations to obtain the polarization parameters.And after calculating the parameters by Fast Fourier Transform,the indirect images were achieved.It was proved that polarization information was an efficient supplement to target strength and spectral information,which can provide more information and improve the resolution.Thirdly,based on theories above,a prototype of indirect imaging system was built.It could modulate spatial phase and orthogonal phase difference,establish measurement table to modulate the structures of sample under test.According to different illumination,camera,samples and other parameters modulation to program an analycial software.It analyzed resources of the probable errors in the measurement model and calibration method.Utilizing the existing the model of CCD model and set up different illumination of image plane of CCD,it modeled and calculated the signal-noise ratio of the conventional images.Compared with the measurement accuracy of indirect images,it built the relation between the signal-noise ratio of the conventional images and the measurement accuracy of polarization parameters indirect images.So that this mothed lucubrated the effects of measurement precision of degree of polarization and polarization angle.During the imaging measurement,it would inevitably produce an optical error,or system error.In this thsis,it reported the impact of detector on imaging precision,but given methods to reduce the noise experimentally.To eliminate the errors which were caused by high numerical aperture,it used pixel unit calibration method which was based on Jone's Pupil.Fourthly,some applications of indirect imaging were introduced.It studied far field inversion algorithm and theory of optical polarization parameter indirect microscopic imaging.And then introduced it was used in measurement of nano-materials graphene,human skin and Renminbi identification by analyzing the experimental results.Compared with other microscopic imaging,this method inherited the merit of rapid and efficiency in wide field optical imaging,had the super resolution,3-dimensional morphology and multi-dimensional image-detected capabilities.At the same time,it also solved the problem of high cost,low repeatability and damage samples and so on.Therefore,it had the great significance on science and engineering.At the end of this thsis,it summarized the main work and looked forward to the prospect of polarization-modulation for indirect microscopic imaging.