Interferometric measuring device for form measurement

US6813029B1 · kind B1 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Michael Lindner · Leutenbach, DE
• Pawel Drabarek · Tiefenbronn, DE

Key dates

• Filing date: Aug 7, 2002
• Grant date: Nov 2, 2004
• Expiry date: May 3, 2023

Classification

• Technology area (CPC G): Physics
• CPC primary: G01B11/303
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The present invention relates to a interferometric measuring device for measuring the shape especially of rough surfaces of a measured object (O), having a radiation-producing unit (SLD) emitting short-coherent radiation, a beam splitter (ST1) for forming a first and a second beam component (T1, T2), of which the first is directed via an object light path to the measured object (O), and the second is directed via a reference light path to a reflecting reference plane (RSP), having a superposition element at which the radiation coming from the measured object (O) and the reference plane (RSP) are brought to superposition, and an image converter (BS), which receives the superposed radiation and sends corresponding signals to a device for evaluation, for the measurement to be taken, the optical path length of the object light path being changed relative to the optical path length of the reference light path. An exact measuring of object surfaces in narrow cavities, in three dimensions, having great accuracy, is made possible by providing in the optical light path an optical probe (OS, OSO) having an optical arrangement for producing at least one optical intermediate image.