Flexible Mueller Matrix Polarimetric Endoscope for Advanced Cancer Screening: Prototype 1 Optomechanics and Miniaturization

Abstract

This thesis presents the design and miniaturization of an imaging fiber-based polarimetric endoscope. Building upon prior work that demonstrated a linear Stokes analyzer through a flexible coherent imaging fiber bundle, this work focuses on translating the system into a compact 5 mm diameter form factor, integrating both the polarization state analyzer (PSA) and the polarization state generator (PSG).For the polarization state generator, two distinct illumination architectures were explored: an on-tip printed circuit board (PCB) design with discrete LEDs arranged around the optical axis, and a fiber-coupled illumination approach. The polarization state analyzer incorporates a pixelated polarizer array aligned with a coherent imaging fiber and micro-lens, forming a compact PSA capable of resolving spatial polarization information in a single snapshot. The design and fabrication process is described in detail, including mechanical tolerances, polarization alignment, and trade-offs in component mounting. The prototype was assembled and evaluated through imaging tests using polarization tar- gets and resolution standards. Results demonstrate the feasibility of polarization-resolved imaging in a miniaturized format and highlight areas for future improvement such as custom lens development and improved mechanical designs. This work establishes a technical foundation for the development of clinically translatable polarization endoscopes and contributes practical design guidelines for optomechanical integration at millimeter scales.