Design and Simulation of Optical System for Dual-wavelength Retinal oximeter

Measuring retinal oxygen saturation has important reference significance for some systemic diseases. The existing fundus examination equipment in the country is still limited to the acquisition of fundus images. The diagnosis of the disease needs to be judged by the doctor's experience. The error is large. How to quantify the retinal oxygen saturation has become a new hot spot in the field of medical instrument science. Based on the characteristics of blood absorption spectroscopy, a non-invasive dual-wavelength retinal oxygen saturation spectrometer with a working wavelength of 570 nm and 600 nm was designed. The illumination and imaging light paths are designed in zemax software and the illumination light path is simulated in tracepro. Then the OTSU method is used to calculate the image threshold, and the gray value with the largest variance between the classes is found as the segmentation threshold, so that the blood vessel and the background are better scored.