3D Refractive Index Estimation Based on Partially-Coherent Optical Diffraction Tomography (PC-ODT) and Deep Learning

A digital microscope comprising:

• an illumination system configured to generate an illumination beam to illuminate a target at a plurality of illumination angles;
• an optical system to direct the illumination beam to the target;
• a refocusing system positioned in a detection path and configured to perform stageless axial refocusing of a measurement beam, wherein the measurement beam is transmitted through the target;
• a detection system configured to capture an intensity stack for the plurality of illumination angles and during the axial refocusing;
• and
• a processor configured to generate a three dimensional refractive index of the target based on the intensity signal.

A method for determining a three dimensional refractive index of a target, comprising

• illuminating the sample at a plurality of illumination angles using an partially incoherent beam;
• performing stageless axial refocusing of a measurement beam, wherein the measurement beam is transmitted through the target;
• capturing an intensity stack for the plurality of illumination angles and during the axial refocusing;
• and
• generating the three dimensional refractive index of the target using a trained neural network.