Method and apparatus measuring edges on a workpiece

US5982491A · kind A · utility

Assignee

• Carl Zeiss Stiftung · DE

Inventors

• Karl-Hermann Breyer · Heidenheim, DE
• Klaus-Dieter Götz · Sersheim, DE
• Rolf Beck · Eßlingen, DE

Key dates

• Filing date: Oct 20, 1997
• Grant date: Nov 9, 1999
• Expiry date: Oct 20, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01B11/005
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention is directed to a method and an apparatus for measuring the edges 13 of a workpiece 5 with an optical probe 4. The probe 4 measures the distance values (a) between the probe 4 and an adjustable scanning point 15. In the method, the scanning point 15 is moved along a loop path (36a, 36b, . . . , 36n) over the edge 13 of the workpiece 5 to be measured in order to obtain more exact values for measured points of the edge at a higher measuring speed. During the method, distance values (a) are measured by the probe 4 and a point P of the edge 13 is determined from the course of the measured values.