Optical Aberration Calibration and Correction of Photographic System Based on Wavefront Coding.

Chuanwei Yao,Yibing Shen

doi:10.3390/s21124011

Abstract

The image deconvolution technique can recover potential sharp images from blurred images affected by aberrations. Obtaining the point spread function (PSF) of the imaging system accurately is a prerequisite for robust deconvolution. In this paper, a computational imaging method based on wavefront coding is proposed to reconstruct the wavefront aberration of a photographic system. Firstly, a group of images affected by local aberration is obtained by applying wavefront coding on the optical system’s spectral plane. Then, the PSF is recovered accurately by pupil function synthesis, and finally, the aberration-affected images are recovered by image deconvolution. After aberration correction, the image’s coefficient of variation and mean relative deviation are improved by 60% and 30%, respectively, and the image can reach the limit of resolution of the sensor, as proved by the resolution test board. Meanwhile, the method’s robust anti-noise capability is confirmed through simulation experiments. Through the conversion of the complexity of optical design to a post-processing algorithm, this method offers an economical and efficient strategy for obtaining high-resolution and high-quality images using a simple large-field lens.

Highlights

State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, China; Citation: Yao, C.; Shen, Y
We used the imaging simulation function of the CODEV software to investigate the effectiveness of the proposed method for reconstructing the point spread function (PSF)
We propose a method for measuring PSF based on wavefront coding

Summary

Introduction

State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310027, China; Citation: Yao, C.; Shen, Y. Obtaining the point spread function (PSF) of the imaging system accurately is a prerequisite for robust deconvolution. A group of images affected by local aberration is obtained by applying wavefront coding on the optical system’s spectral plane. The PSF is recovered accurately by pupil function synthesis, and the aberration-affected images are recovered by image deconvolution. Through the conversion of the complexity of optical design to a post-processing algorithm, this method offers an economical and efficient strategy for obtaining high-resolution and high-quality images using a simple large-field lens. The performance of optical systems depends considerably on the design of the optical system, as aberration is a key obstacle for an optical system to reach the ideal diffractionlimited resolution. To obtain high-quality images, optical imaging systems designers must correct and balance aberrations by combining multiple lenses of different glass materials. Even if the final design of the optical systems meets the requirements, it will make optical systems cumbersome and expensive

Methods

Results

Conclusion