A novel infrared forehead thermometer with ambient temperature compensation for body temperature measurement in low-temperature environment

Abstract

Body temperature screening and measurement using infrared forehead thermometer (IFT), a non-contact thermometer, is an important method to prevent the spread of COVID-19 at present. However, low accuracy and unreliability of current IFT due to ambient temperature effect prevent it application in most of low-temperature environment. The aim of this study was to measure the body temperature accurately using IFT in low-temperature environment. A novel IFT with broad working temperature range and ambient temperature compensation was designed and fabricated, and the performance was evaluated. Also an ambient temperature compensation method based on Bluetooth module was introduced to improve the accuracy of body temperature measurement for the first time. The experiment results demonstrated that the laboratory indication error and repeatability in test mode of this developed IFT were all below 0.2℃ in ambient temperature range of (3~35) ℃. While the extended uncertainty for laboratory indication error was less than 0.1℃ (k=2). Compared with the contact electronic clinical thermometer, the difference of body temperature was improved within the scope of (-0.3~﹢0.3)℃ in low-temperature measurement environment. All the results showed that the IFT fabricated in this paper is sufficient and competent for body temperature screening and clinical body temperature measurement in most of low-temperature environment