Sensors can be implemented in
numerous technologies which can present a bewildering choice.
The main ones are based on magnetism, electric field, piezo,
optics, and thermal effects. These can be sub-divided once again; for
example within magnetism exist hall effect, inductive,
magnetostriction, ....to name but a few.
The physical implementation should also be considered.
Devices can be
individually machined, or employ plastic mouldings; they might be
designed into printed circuit boards or be constucted in silicon as a
All these factors can have considerable bearing on the
cost of the production sensor.