Miniscule Contact Measurement System

The Werth Fiber Probe (WFP) is a special contact measurement system where the probe shaft is used to position the contact sphere. The actual measurement of the position of the sphere is done by an image processing sensor built into the system.

Since the deflection of the sensor is not included in the measurement result, extremely thin shafts and the smallest contact spheres can be used.

The WFP features a tip with a diameter as small as 25µm and a long stylus length – often in excess of 50mm. Because of the small geometry, only very small contact forces are generated by the fiber probe (up to a few µN) for the nondestructive measurement of opticalquality surfaces, deep bores, and extraordinarily small holes and elements. In addition, the fiber probe tip can be illuminated to measure blind or closed features, counterbores and geometries/profiles that cannot be measured by transmitted light.

Features with very small dimensions and very touch-sensitive surfaces can be safely measured. Together with the Werth Zoom, probe lengths of up to 200mm are possible.

Typical applications for this sensor include infinitesimal cranio-facial surgical screws, often with diameter of 0.3mm and less; tiny turbine blade cooling holes; and microscopic-diameter diesel fuel injector spray holes. Additional applications include the measurement of long, small-diameter holes in highstrength polymer extrusion dies, and the characterization of tiny profiles found in vascular stents.