KJT eddy current sensors are capable of static and dynamic non-contact, high linearity, high resolution measurement of the distance of the metal conductor under test from the probe surface. It is a non-contact linearized metrological tool that accurately measures static and dynamic relative displacement changes between the object under test and the probe end face. In the high-speed rotating machinery and reciprocating motion machinery state analysis, vibration research, analysis and measurement, non-contact high-precision vibration, displacement signals, can be continuously and accurately collected to the rotor vibration state of a variety of parameters. Such as radial vibration of the shaft, amplitude and axial position.