센서, 트랜스듀서

Sensors detect physical quantities like temperature and pressure and produce raw signals, while transducers convert one form of energy into usable electrical signals. Generally, industrial transducers consist of sensors plus conditioning circuits for amplification and filtering, meaning sensors belong to transducers.
Transducers fall into passive and active types. Passive ones such as strain gauges work without external power, whereas active ones like thermocouples need power supply. Their vital specifications include sensitivity, accuracy, resolution, hysteresis and response time.
These devices widely apply in factory automation, vehicles, medical instruments and electronic gadgets. They connect physical surroundings with electronic control systems for data collection and automatic control.