Research Of Evaluation Method To Freeform Spectacle Lens By Wavefront Aberration

Freeform spectacle lens has excellent optical properties which can effectively improve the imaging effect of the optical system.The evaluation and accurate measurement of the imaging quality of freeform spectacle lens have great practical significance for the development and application of free surface lenses.In this paper,wavefront aberration is used to evaluate the imaging quality of freeform spectacle lens.The purpose of this study is to study wavefront aberration measurement methods for freeform spectacle lens and to establish a combined lens and eyes system model.The main research contents are as follows:(1)Used the two-dimensional displacement platform to drive the small aperture Shack-Hartmann wavefront sensor movement and adopting the parallel measurement mode to measure the wavefront aberration of the progressive addition lenses in four times.The least squares method is applied to deal with the measurement results,and the stitching parameters of the wavefront aberrations of each sub-aperture are obtained.The wavefront aberration map of the four sub-aperture overlapping regions on progressive multifocal lenses is recovered by mode method.(2)Designed beam expander system makes the beam of the laser sensor launch exit after a beam expander system parallel beam gradually more focus lens in the center of the circular area,get the circular area of wavefront aberration of progressive multifocal lens diameter at 22 mm central point the.The defocus efficients of wavefront aberration is compared with the result of transmission fringe deflection method for measuring the same progressive multifocal lens,which verifies the feasibility of the beam expanding-shrinking optical measurement method.(3)Following the actual physical parameter of human eye design the human eye model,and deduce the optical transfer function of the human eye model and progressive addition lenses,and establish the transfer function model of the lens and eyes joint system.Designed a contrast experiment,and measured wavefront aberration of human eye model,wavefront aberration of lens and eyes joint system wearing a different mirror lens and wearing a same mirror lens,got different parameters of gradual focus more characteristics of the eye lens correction.The study of this paper provides a feasible method for evaluating freeform spectacle lens,which is beneficial to the quality evaluation and application of Freeform spectacle lens.