Hybrid lidar-radar for medical diagnostics

A hybrid lidar-radar system for detecting the presence of tissue inhomogeneities within tissue by detection of reflected and scattered light signals from the tissue and discriminating information related to cancerous tumors from scattering of light created by the tissue itself, comprising:

• a source of microwave energy for providing a microwave subcarrier signal;
• a source of continuous wave light for providing and for transmitting toward the tissue an optical carrier signal that is modulated by the microwave subcarrier signal, said source of light transports the microwave subcarrier signal through the tissue and is reflected and scattered by the tissue, said optical carrier signal has a frequency and said source of continuous wave light comprises:
• first and second lasers each having an operating wavelength of about 1064 nm, said first and second lasers having an optical frequency difference in a range from 0.01 GHz to 60 GHz, each of said first and second lasers having an output;
• a 50/50 optical splitter receiving and combining the outputs of said first and second lasers, said optical splitter having first and second outputs with the first output of the optical splitter transmitted toward the tissue;
• a light source optical detector for receiving the second output of said optical splitter and a mixer for mixing it with a reference signal having a frequency slightly offset from the desired modulation frequency, said mixer providing an output serving as an offset and having an intermediate frequency;
• and
• a laser offset locking assembly receiving the output of said mixer and providing an output signal to each of said first and second lasers that provides coherence between said first and second lasers to said offset intermediate frequency;
• a detector for detecting the scattered and reflected light and for producing electrical signals indicative thereof;
• and
• an optical detector that provides an output signal to a network analyzer that receives said produced electrical signals and measures phase and amplitude differences between the light scattered from the tissue and said optical carrier signal for the detection of said tissue inhomogeneities.