US Patent 7658716 Vital signs monitor using an optical ear-based module

The invention provides a system for measuring blood pressure from a patient that includes: 1) an optical module configured to be worn on the patient's ear and comprising at least one optical source and a photodetector; 2) a calibration source configured to make a blood pressure measurement; and, 3) a processing module configured to: i) receive a first signal from the optical module; ii) receive a second signal from the calibration source; iii) process the first and second signals to generate a calibration table; and iv) receive a third signal from the optical module and compare it to the calibration table to determine the patient's blood pressure.