Research On The Differential Polarization Imaging System And Its Characteristics

As an important instrument for optical remote sensing,polarization interference imaging spectrum system can obtain a relatively clear two-dimensional spatial image and one-dimensional spectral image of the objects.The system based on polarization interference not only has the advantage of high stability,high throughput and high sensitivity but also has the advantage of small size and compact optical path.However,in some challenging situations,the equipment presents a set of problem.For example,if the object is appearing against a natural background and light intensity reflectivity is similar,the object could not be identified from the conventional intensity image.How to obtain more comprehensive information and to optimize the performance of imaging system has become an urgent problem to be solved.The polarization-difference interference imaging spectrum system is a novel multi-function optical device,which can obtain the target's two-dimensional spatial images and interference images for orthogonal polarization direction simultaneously.Through data processing,the system can remove or weaken the influence of the target's background,and improve equipment performance and detection capability of the target to be measured,which is a more effective method to enhance the ability of the imaging system.The two kinds of novel polarizing beam splitter—the modulated polarizing beam splitter?MSP?and the modulated wide-field-of-view polarizing beam splitter?MWSP?are designed.Two kinds of Savart polariscope?MSP and MWSP?about the change range of the optical path difference and lateral displacement are analyzed in detail.Through the contrast between them,it is known the optical path difference is little but the lateral displacement materially is different,that is to say,the lateral displacement of MWSP is 50%higher than that of MSP.It provides a more important reference and guidance for the designing and processing of the polarizing prism in the future.The designed MSP applied to the polarization-difference system,the polarization-difference interference imaging spectrum system with adjustable optical path,based on the Wollaston prism and the lateral shear of SP is presented,which not only can simultaneously obtain the target's two-dimensional spatial image and interference image for orthogonal polarization direction,also can obtain interference image for different optical path difference with the adjustment of the MSP.The significant features of the system are acquiring the orthogonal images simultaneously and changing optical path in real time,which has the advantages of avoiding overlapping images effectively and saving the cost of crystal processing.In view of the shortcomings of the polarization-difference imaging system,an optimized polarization-difference imaging system is designed.The theoretical principle and the expressions for interference intensities of the polarization-difference interference imaging spectrum system with adjustable optical path are demonstrated in this paper.Which have certain reference significance for the performance optimization and practical application of the interference imaging spectrum system.The main innovations of the paper are given as follows.Firstly,the MSP and MWSP are designed.Secondly,the MSP is applied to polarization-difference interference imaging system and the novel polarization-difference imaging spectrum system is presented.In view of the shortcomings of the polarization-difference imaging system,an optimized polarization-difference imaging system is designed.The orthogonal polarization interferogram under different shear quantities and the orthogonal interference images under different polarization states are simulated.Thirdly,Through system debugging and data processing,we get the orthogonal spatial images and the parallel and vertical components of the 632.8 nm monochromatic light for d_MSP=1.00 mm,1.10 mm,1.20 mm,1.30 mm.Even the polarization-difference spectrograms and polarization-difference spatial images are further obtained.The conclusion that the polarization-difference spatial image has a high spectral resolution and spatial resolution compared to the conventional polarization intensity images is obtained.Which have certain reference significance for the performance optimization and practical application of the interference imaging spectrum system.