Research On Microscopic Spectral Imaging Based On The Combination Of Prisms And Gratings

Imaging spectrometer has the characteristic of three dimensional imaging,being applied more and more widely.The purpose of this topic is to apply imaging spectrometer to microscopy,and to design the microscopic spectral imaging system which meets the requirements to achieve microscopic spectral imaging.Researched on AOTF,LCTF and PGP which are in common use with imaging spectrometer as dispersion means,including principle,market research and the summary of technological advantages and disadvantages,combined with design requirements,compared their advantages and disadvantages,and at last selected PGP as the dispersion means of microscopic spectral imaging system.Through research on the application of prism and gratings as PGP important components,including working principle,the theoretic analysis and the calculation of angular dispersion,the theoretic analysis and the calculation of spectral resolution,on the base of the Coupled Wave theory and Bragg theory of volume holographic gratings,used Matlab to analyze the diffraction efficiency of volume holographic gratings from PGP components and drew diffraction efficiency curve,finally to prove the feasibility of PGP module.Refered on the optical system structure of imaging spectrometer based on PGP components,followed the module design thought,designed 1.7X interface lens,collimator,imaging lens and PGP module,described the pupil match problem and the numerical aperture match problem,while determined several main characteristics of microscopic spectral imaging system,including work spectrum district,field,space resolution,spectral resolution and so on.Through research on 20 X micro lens,and 0.69 X tube lens,used Zemax for human-computer interaction optimization.At first,designed two 1.7X interface lens based on 0.69 X tube lens,compared them,and eventually selected 1.7X short interface lens as the 1.7X interface lens.Then designed collimator,imaging lens and PGP module,used spot diagram,modulation transfer function,the relative luminance curve,distortion curve for image quality evaluation.Finally through the calculation of spectral resolution of PGP-Imaging module and description of spectral smile,indicated that the design of microscopic spectral imaging system meets the requirements.