In active sensor we have voltage generation, or better things which resemble voltage generators, which are:
- electrochemical (for chemical compound).
- electromagnetic (this is for speed, essentially).
- thermoelectric (for temperature).
- charge generator, this have high internal impedance, to connect to what we have seen some less than ago, and this can be further divided in:
- piezoelectric (for strain and stress).
- electrochemical (for chemical compound), this is a chemical and chemical sensor. It sends some specific compound obviously not all.
- optoelectronic, this uses the optical power.