Research On Polarization Imaging Resolution Of Partially Coherent Light Illumination

The problem of two-point resolution has been discussed with many criteria and methods.The most famous ones are the Rayleigh criterion and Sparrow criterion.However,they are usually only applicable to the two limit states of completely coherent light or completely incoherent light.There are few general researches on partially coherent light.In this paper,a partially coherent light-illuminated circular aperture imaging system is designed.By changing the distance between two points in space and controlling the degree of coherence of the light source,a mathematical model of the distribution of two object points on the image plane is established.This system is compared with the traditional partial coherence model.The resolution accuracy is improved,and the two-point resolution model with arbitrary coherence and arbitrary spacing is obtained by changing the coherence degree of the light source and the distance between two holes.Due to the diffraction effect,the distance between two points on the image plane is different from the distance between the actual object points.This paper gives the ratio R between the distance between the image plane and the object plane to describe the system's ability to distinguish between two object points.After introducing a set of normalization factors(the order of the generalized Stokes parameter),the spatial resolution problem in the polarization imaging system is re-discussed,that is,the problem of the Stokes parameter resolution between two points in space,and the accuracy of polarization imaging Criterion.Under the same lighting conditions,the two dense points that are distinguishable for a certain Stokes parameter will become indistinguishable for other Stokes parameters.In this article,the two-point resolution of the imaging space illuminated by partially coherent light will be studied from the three states of non-polarized,partially polarized,and fully polarized,and the law of resolution under multiple factors will be obtained and passed Simulation and experiment to verify.At the same time,this paper selects a distance slightly close to the Sparrow criterion to carry out experiments,and obtains that when the coherence of the light source is constant,it can always be resolved,just resolved,or cannot be resolved at any distance,and the general resolution law of circular aperture imaging system with arbitrary coherence is given.This paper also studies the imaging law of edge objects with arbitrary polarization and coherence.Under this line resolution,referring to the method of representing the step response in the field of electronics and automatic control,three new parameters Rise-distance,Setting-distance and Overshoot are proposed to describe the correlation of the optical system from start to stop feature.Among them,Rise-distance is used to describe the distance that the optical system "from scratch" passes through the beam in the excitation signal.Setting-distance is used to describe the distance required for the optical system from oscillation to stability.Overshoot describes the relationship between the maximum value reached during the oscillation process and the stable value.At the same time,this paper presents the relationship between the three new parameters and the coherence area.Finally,this paper proposes the spatial resolution criterion of polarization imaging to describe whether the two points in the Stokes parameter can be resolved under the conditions of coherence and polarization changes of illumination.The normalized generalized Stokes parameter and coherence are studied.The influence of the two degrees on the resolution of two points in space,and establish the relationship between the two,and give a specific expression;according to the proposed spatial resolution basis or criterion,the parameter interval is determined,It is possible to always distinguish or not to distinguish,and establish the relationship between the parameters.