Noncontact temperature measurement of human hand skin using volume phase holographic optical element based digital holographic interferometer. (April 2022) - Rastogi, Vivek
Highlights: Digital holographic interferometric based system is non-invasive and non-contact type. Measurement is independent of distance between the skin and sensor. Measurement will not disseminate the virus and contagious diseases. Abstract: Measurement of surface temperature of human body skin is one of the basic and standard diagnostic tool for health management. The temperature of the human body is a vital sign of health status and it is used for medical diagnosis. Generally, contact type temperature sensors are used for temperature monitoring; however, accuracy of these sensors is limited due to the skin-sensor interface, sensor physical dimensions, and sensor pressure. This paper demonstrates an application of digital holography to measure the temperature of human hand skin (index finger and palm skin). The heat energy emitted from the human body flows as convection current in the air and cause a change in refractive index in air field around human body which leads to change in phase of object wave. A volume phase holographic optical element based digital holographic interferometric (DHI) system has been used in a lensless Fourier transform (LLFT) configuration to measure the temperature of human skin from the reconstructed phase difference of air surrounding the human body and ambient air. The surface temperature of human skin measured by volume phase holographic optical element based DHI system shows a good agreement with the temperature measured by a commercially available digital and infrared thermometer.