Inductive sensors 感應感測器Inductive sensors work only on AC signals.Self- and mutual inductance type may not be linearly related to displacement.LVDT characteristics include linearity over a large range, a change of phase by 180o when the core passes through the center position.LVDTs have much higher sensitivity than that for strain gage.LVDT requires more complex signal-processing instrumentation, e.g. phase-sensitive