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
Indoor–outdoor thermometer Indoor–outdoor thermometer An indoor–outdoor thermometer is a thermometer that simultaneously provides a measurement of the indoor and outdoor temperatures. The outdoor part of the thermometer requires some kind of remote temperature sensing device. Conventionally, this was done by extending the bulb of the thermometer to the remote site. Modern instruments are more likely to use some form of electronic transducer. In an indoor–outdoor thermometer based on a conventional liquid-in-glass thermometer, the stem of the outdoor thermometer is connected to the bulb by a long, flexible or semi-rigid capillary. The temperature scale is marked on the stem as usual. However, the