2 - Sensor principles and basic designs

Abstract

Sensors have become pervasive and essential in the modern industrial world. Their applications range from sophisticated industrial processes to common consumer products. A sensor is defined as a device that receives a signal or stimulus and responds to it by generating an electrical signal. The output signals correspond to some forms of electrical signal, such as current or voltage, which can be easily measured. Sensors can be classified into different types on the basis of the applications, the input signal, the conversion mechanism (i.e., the transduction principle), the materials used in their design, or sensor characteristics, such as cost, accuracy, dynamic range, etc. This chapter presents an overview of sensors and their basic definitions and terminology to establish some consistency in discussions of sensor applications and technologies, since considerable ambiguity exists in sensor definitions and classifications. Sensor classification based on different transduction principles (e.g., thermal, magnetic optical, mechanical, chemical) was also reported.