2. Classification of transducers according to the transduction principle used

2.1 Possible types of classification

Sensors in general, and displacement sensors in particular, can be classified in many different ways. One way, for example, is to distinguish between sensors that merely modify the electrical quantity applied to them (passive sensors) and those that are capable of generating an electrical quantity (active sensors). Another way of classifying them is to consider the type of output delivered by the sensor: digital or analog. The nature of the connection between the fixed and moving parts can also serve as a criterion, in which case the measurement principle (contact or non-contact) is considered. Measurement range or sensor resolution are not generally admissible as classification criteria, even though they are usually the first choice criteria for...