7 - Imaging and Controlling Light Propagation Deep within Scattering Media Using a Time-Resolved Reflection Matrix

Summary

In this chapter, we introduce two noteworthy methods for exploring the use of the so-called time-resolved reflection matrix (TRRM) of the scattering medium. TRRM is made of the amplitude and phase maps of reflected waves taken at specific arrival time and for various angles or positions of illumination. It provides us with unprecedented amount of information covering both spatial input-output correlation and temporal response. With the vast amount of information at hand, studies have been conducted to relieve the limitations of imaging depth and energy delivery that the multiple light scattering imposes. In section 2, we describe a time-domain approach for measuring TRRM and its application for dramatically improving imaging depth that maintains diffraction-limited spatial resolution. Spectral-domain approach of measuring TRRM is introduced in section 3 along with its application for enhancing energy delivery to the target depth by the implementation of time-dependent eigenchannels.