Optical device with an illuminating grid and detector grid arranged confocally to an object

US5239178A · kind A · utility

Assignee

• Carl Zeiss AG · DE

Inventors

• Eberhard Derndinger · Aalen, DE
• Rudolf Grosskopf · Königsbronn, DE
• Klaus Knupfer · Oberkochen, DE

Key dates

• Filing date: Nov 8, 1991
• Grant date: Aug 24, 1993
• Expiry date: Nov 8, 2011

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B21/0084
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A device is described for three-dimensional examination with a confocal beam path, in which an illumination grid (12; 22; 31; 83) is imaged in a focal plane (13f; 87), said plane being located on or in the vicinity of surface (14o) of object (14). The radiation reflected in the focal plane is imaged directly by a beam splitter onto the receiving surface of a CCD receiver (17; 91). The illumination grid (12; 22; 31; 83) is then imaged on the receiver surface either by the photosensitive areas of the receiver acting as confocal diaphragms or by signals from the detector elements which only receive light scattered outside focal plane (13f; 87) not being taken into account in the evaluation or being taken into account separately. The illumination grid size generated in focal plane (13f; 87) can be either fixed or variable. A variable illumination grid size can be produced for example by an LED array. The device also makes examinations in transmitted light possible.