A sensor is a device or device that can sense a specified measured ( physical quantity, chemical quantity, biomass, etc. ) and convert it into an available output signal ( generally electricity ) according to a certain rule . Sensors are sometimes referred to as detectors or transducers. The output signal has different forms, such as voltage, current, frequency, pulse, etc., to meet the requirements of information transmission, processing, recording, display and control.
In the automatic detection and automatic control system, the sensor is at the head of the system, and its function is equivalent to the five senses of the person, directly sensitive to external information. Therefore, whether the sensor can correctly sense the information and convert it into the required signal according to the corresponding law plays a decisive role in the quality of the system. The higher the degree of automation, the greater the dependence of the system on the sensor. Therefore, sensors are listed as high-tech at home and abroad, and sensors in developed countries such as the United States and Japan have received much attention.
Since the 1980s, when human society entered the society with a highly industrialized society, the importance of sensor status has become more prominent. The three basics of modern information technology are information acquisition, transmission and processing technologies, namely sensor technology, communication technology and computer technology. constitute the iT system "senses", "nerve" and "brain." the image of that, if the "sense" out of order, it gives a distorted information, then the "neural information" transmitted in itself is wrong information, clever "brain" is powerless. Therefore, the last decade, developed a new understanding and evaluation of the role of sensors in the information society of the United States to be seen as the 1980s era sensor, the sensor technology as Japan At the head of the top ten technologies, the former Soviet Union’s “Military Aerospace†program also listed sensor drums as a key development technology.
The importance of the sensor is also reflected in its wide application in various subject areas. Such as industrial automation, agricultural modernization, aerospace technology, military engineering, machine technology, resource exploration, marine development, environmental monitoring, security, medical diagnosis, household appliances, etc. Moreover, sensor technology has also contributed to the development of the above-mentioned various cities.