S194-Imaging through scattering media by 3D spatial filtering embedded into micro-endoscope.

Abstract

The main objective is related to the capability of integrating into minimally invasive and ultra-thin disposable micro-endoscopic tool, a modality of realizing high-resolution imaging through scattering medium such as blood while performing medical procedure. In this research we aim for the first time to present a time-multiplexing super-resolving approach exhibiting enhanced focus sensitivity, generated by 3D spatial filtering, for significant contrast increase in images collected through scattering medium. Our innovative method of imaging through scattering media provides imaging of only one specific object plane in scattering medium's volume while suppressing the noise coming from all other planes. The method should be assisted with axial scanning to perform imaging of the entire 3D object's volume. In our developed optical system noise suppression is achieved by 3D spatial filtering approach while more than an order of magnitude of suppression is experimentally demonstrated. The sensitivity to defocus and noise suppression is dramatically enhanced by placing an array of micro-lenses combined with pinholes raster positioned between two modules of telecentric lenses. We present our novel conceptual designs for the enhanced signal-to-noise ratio (SNR) when imaging through scattering medium and present preliminary experimental results demonstrating both quality imaging performed on resolution bars target as well as SNR quantified results in which SNR enhancement of more than one order of magnitude was obtained. In this paper, to the best of our knowledge, we present the first ever design of time-multiplexing-based approach for super-resolved imaging through scattering medium. The approach includes a time-multiplexing optical design significantly increasing the depth of focus sensitivity and after performing axial scanning yielding a significant enhancement of the SNR of the 3D object that is being imaged through the scattering medium. Right after the contrast (the SNR) enhancement we scan the object with the projected array of spots (raster) and map it continuously and with high imaging resolution.