What are Sensors, Detectors, and Transducers?

Sensors, detectors and transducers are electrical, opto-electrical, or electronic devices composed of specialty electronics. They are sensitive materials and are used for determining if there is a presence of a particular entity or function.


Many types of sensors, detectors, and transducers are available including those for detecting a physical presence such as flame, metals, leaks, levels, or gas and chemicals, among others. Some of them are designed to sense physical properties – temperature, pressure or radiation. Some can also detect motion or proximity.

Classification Of Sensors

  • Different authors and experts made several classifications of sensors. Some are very simple and some are very complex. An expert might have used the following classification of sensors in the subject. It is indeed a very easy classification.
  • In the first classification of the sensors, they are divided in to Active and Passive.
  • Active Sensors are those which require an external excitation signal or a power signal.
  • Passive Sensors, on the other hand, do not require any external power signal and directly generates output response.

Know more on how sensors work, mainly in fashion and fabric.

  • The other type of classification is based on the means of detection used in the sensor. Some of the means of detection are Electric, Biological, Chemical, Radioactive etc.
  • The next classification is based on conversion phenomenon i.e. the input and the output. Some of the common conversion phenomena are Photoelectric, Thermoelectric, Electrochemical, Electromagnetic, Thermooptic, etc.
  • The final classification of the sensors are Analog and Digital Sensors.
  • Analog Sensors produce an analog output. An analog output is a continuous output signal (with respect to the measured quantity).
  • Digital Sensors, in contrast to Analog Sensors, work with discrete or digital data. The data in digital sensors used for conversion and transmission, is digital in nature.  


Sensors, detectors and transducers operate in a variety of manners depending on the application and may include electromagnetic fields, or optics, among others. Many applications over a wide range of industries use sensors, detectors, and transducers of many kinds to test, measure, and control various processes and machine functions.

Do mention in the comments section if you would like to know more about the latest scientific trends.