How is the common thermometer is classified?

Thermometer is mainly used to measure the temperature in the various environment, common thermometer, mainly according to its working principle is different to classify. We can put the thermometer into glass rod thermometer, gas thermometer, solar thermometer and so on. Glass rod thermometer is made by using the properties of liquid heat bilges cold shrink. It commonly used liquid mercury, kerosene and alcohol as the display medium, which is so called the mercury thermometer, kerosene and alcohol thermometer thermometer. Gas thermometer, the use of certain properties of gases, Such as the volume or pressure) With temperature change characteristics, generally made of hydrogen and nitrogen. This kind of thermometer with high accuracy, wide measuring range, used for precision measurement. Solar thermometer, is a use of solar energy and provide accurate temperature indicating wired sensors. It is the light level is higher than 100 lux show, when the light levels drop, using the backup battery to provide power to continue to display circuit. It display material generally is LCD. Bimetallic thermometer working principle is to round shape into threaded heat bimetallic strip as thermal devices, and put it in a protective sleeve tube, one end is fixed, known as the fixed end, the other end of the connection on a thin shaft, called the free end. Spool at the free end is equipped with a pointer. When the temperature changes, the resulting thermal devices the free end of the rotation, drive the thin axis from the Angle of the pointer changes, corresponding temperature indicator on the dial.