Depth and Refractive Index Extraction from Water-Based Phantoms Using an Iterative Algorithm with Combined OCT and THz Imaging

Terahertz (THz) imaging and optical coherence tomography (OCT) are of great importance in non-destructive testing and medical diagnostics, offering complementary data on similar length scales. This study primarily investigates a method designed to enhance our understanding and measurement of hydrated biological samples by merging OCT and THz data through an iterative algorithm. Initially applied to a flat silicone step wedge with varying thicknesses, the method was validated and extended to gelatin samples with varying water content. By integrating multiple measurements from different sample locations, the algorithm not only confirms the expected refractive indices but also consistently determines thickness measurements. The demonstrated utility of this approach in accurately assessing biologically relevant materials highlights its potential application of interest in corneal diagnostics. Such advancements are particularly vital for improving the accuracy and reliability of measurements crucial for managing corneal diseases.