Preliminary Study Of Retinal Blood Oxygen Measurement Based On Optical Low-coherence Interferometry

Double wavelength Optical Low-coherent Interferometry (OCI) here is proposed to measure the oxygen delivery in human retinal blood vessel.In this report, first detailedly analyze what is Optical Low-coherent Interferometry, then demonstrate the principal of its measurement to oxygen saturation in human retinal blood vessel. The absorption of oxygenerated hemoglobin depends on the wavelength of the incident light, so here one absorption maximum and one absorption minimum wavelengths are simultaneously used to estimate the oxygen delivery in the human retinal blood vessl.By giving the simple model of human eye blood vessel, a capillary with innerdiameter 200μm, Matlab numerical analysis is done to estimate the absorption of theblood, which verified the flexibility of this project. And it gives a result when oxygen saturation increases from 40% to 60%, OCI system needs a sensitivity at least -70dB. Meanwhile, two preliminary experiments are done to enhance the confidence of this project and further procedure has been defined based on these results.Then a single wavelength system has been set up with fundamental experiments to prepare the next project step, the transfer of the technology to real blood application.This report also gives the detailed signal processing procedure.