Theoretical Research On Multi-channel Polarization Interference Imaging System

Nowadays,the technology of the interference imaging spectroscopy has become the leading edge of imaging detection.The technology is a scientific hot spot,because it's widely used in the earth exploration,the field exploration,the ocean exploration,the military defense,the environmental detection and the biomedicine.Because of the efforts of scientists,this technology has developed rapidly.In the preceding work,a new interference imaging spectrometer is devised.The system has four channels to acquire four target's images.The advantages of the design are that the slit is replaced by a field view stop.And rotating and moving parts are disposed.Combining the polarization splitting prism with the Savart plates,a beam light can be separated into four pairs of beams.Four interference fringes that can be obtained in the detectors have diverse information.Spectral images can be acquired by use of the Fourier transform algorithm and image processing.Expressions for the interference intensities are presented.The total image of the target is acquired by the summation of the four interferograms;the difference of the interference intensities in the same CCD is equivalent to the pure interference fringes;the difference or summation of two pure interference fringes of the different CCDs is equivalent to the single channeled interference fringes.The curves of the optical path difference varying with wave length,incidence angle,incident azimuth angle and Savart polariscope thickness are described.The fringe distribution is analyzed,then the lateral displacement and the focal length of the lens are designed.At the same time,the thickness of the crystal is discussed.This study provides a theoretical and new solution for the design and application of interference imaging spectroscopy.But in the course of our research,we find that the Savart plate can be replaced by the parallel beam splitting prism.It can eliminate the impact of multi-beam interference generated by oscillating reflection on the two surfaces of the air gap.At the same time,the advantages of the design are that the absorption of light can is reduced and system volume is smaller.Based on these findings,the interference imaging spectrometer based on the parallel beam splitting prism is designed,in which the Savart plate is replaced with the parallel beam splitting prism.This method can reduce the system volume and increase the luminous flux to achieve compact and miniaturized design.The characteristics of the system are studied theoretically and experimentally.By use of the Stokes vectors,the imaging principle of the interference imaging spectrometer based on the parallel beam splitting prism is analyzed.The expression of the interference intensity of the system is obtained.When the thickness is different,the distribution of interference intensity in spatial position is discussed.A new method designing the thickness of crystals is provided.The variation of interference intensity with wavelength and space position is discussed.Compared with the interference imaging spectrometer based on the Savart plate,the significant advantages of the design have the higher spectral resolution,the larger lateral displacement,the higher stability against vibration without moving parts and the higher crystal utilization rate.The optical path of the system is simulated by the Zemax.So the simulated interference fringes are obtained.At the same time,the influence of different incident angles on interference fringes and the view angle of the system are analyzed.This is an analytical method to consider the impact of all components on the field of view.Finally,interference fringes under monochromatic light are obtained.The distribution of interference intensity in spatial position is provided.The distortion of fringe on the edge is analyzed.When the light source is changed,the original target image is obtained.A polarization technique is used to acquire the Stokes vectors images and the polarization degree image,which can enhance the target and help to monitor the target.The feasibility of the interference imaging spectrometer based on the parallel beam splitting prism is verified and it has broad prospects as a detection tool in scientific areas and industrial fields.