Constructing Large Transmission Matrix of Scattering Sample Based on Super-Resolution Algorithm

Abstract

A method to construct a large transmission matrix (TM) of highly scattering media based on an algorithm is presented. For imaging through scattering media, measuring a large TM enables image reconstruction with high spatial resolution; however, it is difficult to operate in practice because the time required for the calibration of the TM is proportional to the number of calibrated input modes. Instead of directly achieving calibration using advanced hardware, a large TM is defined and constructed based on a multiframe image super-resolution algorithm, which traditionally aims to recover a high-resolution (HR) image of the original object from several low-resolution images. With sufficient size improvement, the defined large TM is constructed from several naturally measured complementary small TMs, each of them is measured using a subpixel-shifted projector phase mask. The realized large TM, which is constructed through subpixel registration and interpolation operations at the help of a hypothetical HR mask, enables HR image reconstruction from the original object's speckle signal. The feasibility of the proposed method is proven via optical experiments involving statistical analysis and image reconstruction. The proposed method benefits existing TM-based image reconstruction applications and offers a new perspective on the size of TM measurements and the imaging resolution.