Difference Between Sensor and Transducer
Sensor and Transducer are devices which are used in electronic and electrical devices. Sensor measures a physical quantity and converts it into signals readable by other instruments and the users. Transducers are electrical, photonic, photovoltaic or electromagnetic devices which covert a specific type of energy into another type of energy or a physical attribute for transfer or measurement of information.
Transducers are found in sensors and this leads to confusion between these two terms. To understand the difference you can say that transducers covert one form of energy into another while sensors are used for measuring and indicating the level of measurement.
Many sensors use contact transducers for detecting the level of energy and then converting it into electrical energy. This influences the display meters. These contact transducers were very common in 1980’s in the tape heads of the cassette players. These transducers read the magnetic information by touching the magnetic tape and converted it into electrical signals. These electrical signals were converted into sound waves when they were carried to the speakers by the wires.
Another type of transducers, used in liquid environments, were known as immersion transducers. These were able to measure pressure, sound and other forms of mechanical energy. Paintbrush Transducers work in air just like immersion transducers worked in liquid environments. You can see their usage in the radio antennas which catch radio waves from the air. These radio waves are then converted into electrical energy and then finally sound energy.
Sensors are simpler devices which serve just one purpose of converting the energy into a form that can be understood by the people. Sensors use transducers for this purpose and in most of the cases the energy is converted into electrical energy and then sensors display it with analog meter or through digital display.