https://thenextweb.com/science/2021/02/13/temperature-scanners-wont-stop-covid-19-syndication/
But to be useful mass-screening tools, infrared thermometers also need to be accurate – and this is where problems arise.
In certain, highly controlled circumstances, an increased forehead temperature can indicate a raised deep body temperature – this is why people put their hand on your forehead when you say you don’t feel very well.
But the problem is, forehead or skin temperature can be increased or decreased independently of deep body temperature, for many reasons.
Hand-eye coordination
Looking at these parts of the body and the difference in temperature between them could provide a more accurate indication of whether deep body temperature is raised due to fever.
As a result, the difference between the temperature of the eye and fingers decreases.
But with fever, deep body temperature increases while the hands get colder, so the difference between the eye and finger temperature increases.
thermometer : 온도계, 체온계
invasive : 급속히 퍼지는, 침습성의
extremity : 맨 끝, 손발
