Non-contact measurement system and method for determining the contour of an electrically conductive surface

A non-contact measurement system for determining the contour of an electrically conductive surface relative to a fixed reference point comprising a support arm journaled at one end to a bearing providing a fixed reference point and adapted to extend toward a conductive surface having a contour to be determined and a non-contact probe coupled to the support arm by a precision lead screw driven by a stepper motor which moves the probe either toward or away from the surface and which generates an electrical signal indicative of its axial position from an initial reference position. Control circuitry coupled to the stepper motor is operable to direct the stepper motor to extend the probe toward the surface until it reaches a predetermined distance from the surface. The measurement process is repeated in a plurality of positions separate from the initial position to yield data indicative of the distance from the fixed reference point to the other position points and thereby create a data representative of the contour of the surface. An initial point may be provided separate from the conductive surface and the reference point may be placed in a plane to determine cylindrical and plane test surfaces.