>"Infinite Resolution

Since an LVDT operates on electromagnetic coupling principles in a friction-free structure, it can measure infinitesimally small changes in core position. This infinite resolution capability is limited only by the noise in an LVDT signal conditioner and the output display's resolution. These same factors also give an LVDT its outstanding repeatability."

Related: https://en.wikipedia.org/wiki/Linear_variable_differential_t...

>"A counterpart to this device that is used for measuring rotary displacement is called a rotary variable differential transformer (RVDT)." (https://en.wikipedia.org/wiki/Rotary_variable_differential_t...)