Photosensitive probes

Abstract

Probes according to the present invention practice a method of emitting light when the probe is positioned within a predetermined range of a workpiece surface, positioning the probe at a fixed position within the predetermined range of said workpiece, variably shaping the beam in response to variations of the relative distance between the probe and the workpiece within the predetermined range, and sensing a predetermined portion of the shaped beam when the workpiece surface is positioned at a point within the predetermined range, whereby the illumination intensity sensed varies substantially linearly throughout the predetermined range. In a non-contact form of the probe, the illumination is directed to vary the area of the light reflected from the workpiece surface in order to change illumination intensity at the sensor. In a contact form of the invention, a shade between a light source and a photosensitive receiver is displaced in response to plunger movement as the plunger engages the workpiece.

Dependencies are inferred from the claim text.