| 摘要 |
<p>A capacitance sensing probe is disclosed for taking measurements of features on a workpiece surface. The probe has two electrodes (E1, E2) spaced apart in the direction of movement of the probe with the electrodes being disposed in an attitude normal to the surface. Only the edge of the electrodes are exposed to the surface and an electric circuit (EC) is provided for determining the effect of the surface on the fringe field capacitance between the electrodes. Guard electrodes are used to reduce the stray capacitance being measured. Various embodiments are shown with different numbers and arrangements of electrodes.</p> |
