In 1600 AD, Garylo developed a gas thermometer. Until 1821 was found by German physicist Sebeck to produce a thermocouple sensor to measure the temperature by the Sebeck effect that turned the temperature into a electrical signal. Contribution. In the early days, due to the technical restrictions, the sensor could not implement the two functions of measurement temperature and humidity at the same time. Therefore, in order to measure the two important parameters of temperature and humidity, the temperature sensor and humidity sensor had to be used at the same time.

One hundred years later, it was developed into an alcohol thermometer and a mercury thermometer.

With the development of modern industrial technology, metal wire resistors, temperature difference electrical elements, and dual metal temperature sensors have been developed one after another.

After 1950, the semiconductor thermistor was successively developed. Recently, with the rapid development of raw materials and processing technology, various types of temperature sensors have been developed one after another.

Since then, with the development of technology, people have developed various temperature and humidity sensors. This century, with the support of semiconductor technology, semiconductor thermocouple sensors , PN temperature sensors and integrated temperature sensors were born. Correspondingly, in accordance with the laws of waves and material interaction, acoustic temperature sensors, infrared sensors and microwave sensors were successively developed. There are four main types of temperature sensors: thermocets, heat -sensitive resistance, resistor temperature detector (RTD) and IC temperature sensor.

The thermocouple sensor has its own advantages and defects. The sensitivity of the thermocouple temperature sensor has nothing to do with the thickness of the material. It can also be made into a temperature sensor with very fine materials. Because the metal material of the production of thermocouple has a good ductility, this subtle temperature measurement element has a very high response speed, which can measure the process of rapid changes. However, the sensitivity of the thermocouple sensor is relatively low, it is easily affected by the environmental interference signal, and it is also easily affected by the temperature drift of the front amplifier. Therefore, it is not suitable for measuring small temperature changes.