PHOTOPLETHYSMOGRAM DEVICE WITH SKIN TEMPERATURE REGULATOR

A photoplethysmogram device is provided comprising a light source configured to emit light to illuminate skin, a photo-detector configured to receive the light illuminating the skin and generate an electrical output as a function of an intensity of the received light, a skin temperature regulator configured to heat and/or cool a temperature of the skin adjacent to the photo-detector and light source to increase the signal-to-noise ratio (SNR) of the electrical output from the photo-detector, and a processor configured to generate, based on the electrical output, an output signal indicative of blood properties, including physiological parameters such as blood pressure, heart rate, stroke volume, cardiac output, total peripheral resistance, blood vessel elasticity, and arterial oxygen saturation.