Generalized aberration regularization in the single-lens computational imaging system design.

The restoration algorithm can reduce the aberration blur in the single-lens computational imaging system. The single lens and the restoration algorithm should be co-designed to improve the imaging performance of the whole computational imaging system. By investigating the influence of aberrations on computational imaging quality, we find there are aberrations that cannot be removed by restoration algorithm, which cause the loss of high-resolution information. However, such aberrations are not constrained in existing co-design methods. To solve this problem, we propose the generalized aberration regularization (GAR), which mainly constrains the aberrations that reduce the modulation transfer function (MTF) at the high frequency. Experimental results demonstrate that our approach can significantly improve the quality of high-resolution information in the recovery image compared with the existing co-design methods.

End-to-end learned single lens design using improved Wiener deconvolution.

End-to-end single-lens imaging system design is a method to optimize both optical system and reconstruction algorithm. Most end-to-end single lens systems use convolutional neural networks (CNN) for image restoration, which fit the transformation relationship between the aberrated image and the ground truth image in the training set. Based on the principle of optical imaging, we realize non-blind image restoration through Wiener deconvolution. Wiener deconvolution is improved with the powerful fitting ability of depth learning so that the noise parameters and the blur kernel in Wiener deconvolution can be simultaneously optimized with the optical parameters in the lens. Extensive comparative tests have been conducted to demonstrate the single-lens imaging system obtained by our method has more stable imaging quality and a 40 times greater imaging speed than the method using CNN restoration algorithm.