Techopedia explains Transducer
Some examples of transducers are:
- Position and pressure sensors
Although not commonly viewed as transducers, light emitting diodes (LEDs), photocells and, in many cases, common light bulbs may be considered as transducers.
There are various kinds of transducers; however, at their most basic, transducers are often categorized into two groups: input (sensor) and output (actuator). Input transducers consume some form of physical energy, such as pressure, temperature or sound waves, and then transform it into a signal that can be read. For instance, a microphone can convert sound waves into an electrical signal, which can be broadcasted through wires. A pressure sensor converts the physical force being applied on it into a reading or a number that can be understood without difficulty.
Actuators consume an electronic signal and then transform it into physical energy. An example is a stereo speaker, which functions by converting a recording's electronic signal into physical sound waves. Another standard type of an electromechanical transducer is an electric motor, which converts electrical energy into mechanical energy to carry out a task.
Efficiency is a vital factor when considering transducers. Transducer efficiency is described as the ratio of the power output in the preferred type to the total power input. Basically, no transducer is completely efficient; a certain amount of power is often lost during the conversion process.
Some transducers are usually more efficient than others. An illustration of an efficient transducer is a radio antenna, which converts radio frequency power into an electromagnetic field. If the antenna is operating properly, this process might be 80% or more efficient. On the other hand, nearly all electrical motors function below 50% efficiency. At the same time, standard incandescent light bulbs lose a considerable amount of energy as heat, and, hence, they function below 10% efficiency.