Medical thermometer and displaying temperature became available, electronic thermometers (often called "digital", because they display numeric values) have been used. Many display readings to great precision (0.1 °C or 0.2 °F, sometimes half that), but this should not be taken as a guarantee of accuracy: specified accuracy must be checked in documentation and maintained by periodical recalibration. A typical inexpensive electronic ear thermometer for home use has a displayed resolution of 0.1 °C, but a stated accuracy within ±0.2 °C (±0.35 °F) when new. The first electronic clinical thermometer, invented in 1954, used a flexible probe that contained a Carboloy thermistor. Types
Liquid crystal thermometer and it is put onto someone's forehead it will change colour depending on the temperature of the person. There are two stages in the liquid crystals: Liquid crystal thermometers portray temperatures as colors and can be used to follow temperature changes caused by heat flow. They can be used to observe that heat flows by conduction, convection, and radiation. In medical applications, liquid crystal thermometers may be used to read body temperature by placing them against the forehead. These are safer than a mercury-in-glass thermometer, and may be advantageous in some patients, but do not always give an exact result,