Classification of sensors (or transducers) based on physical stimuli

 

Classification of Sensors

The scheme of classifying sensors can range from very simple to very complex. The stimulus that is being sensed is an important factor in this classification.

Some of the stimuli are

  • Acoustic: Wave, spectrum, and wave velocity.
  • Electric: Current, charge, potential, electric field, permittivity, and conductivity.
  • Magnetic: Magnetic field, magnetic flux, and permeability.
  • Thermal: Temperature, specific heat and thermal conductivity.
  • Mechanical: Position, acceleration, force, pressure, stress, strain, mass, density, momentum, torque, shape, orientation, roughness, stiffness, compliance, crystallinity, and structural.
  • Optical: Wave, wave velocity, refractive index, reflectivity, absorption, and emissivity.

The sensors’ conversion phenomenon is also an important factor in the classification of sensors. Some of the conversion phenomena are 

  • magnetoelectric, 
  • thermoelectric 
  • photoelectric.

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