Automatic focusing device for an optical appliance

US6825454B2 · kind B2 · utility

Assignee

• Carl Zeiss Microelectric Systems GmbH · DE

Inventors

• Norbert Czarnetzki · Jena, DE
• Thomas Scheruebl · Jena, DE
• Stefan Mack · Berlin, DE
• Toshiro Kurosawa · Hachioji, JP
• Eckard Hagemann · Jena, DE

Key dates

• Filing date: Feb 19, 2004
• Grant date: Nov 30, 2004
• Expiry date: Feb 19, 2024

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B21/245
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

The invention is directed to an arrangement for autofocusing onto a measuring location on an object moving in a direction which is at least approximately vertical to the optical axis of the imaging optics. According to the invention, a diaphragm device is to be provided the diaphragm opening of which extends in a direction aligned with the direction of movement of the measuring location; a receiving device for the measuring light has receiving areas arranged in a row beside each other and is inclined relative to the optical axis so that the image from the diaphragm device is incident on the receiving areas at an inclination of an angle &agr;; wherein the receiving device and the diaphragm opening are positioned relative to each other in such a way that characteristic measuring values are measured on the receiving areas when the measuring location is in or near the focus position. An evaluating device compares the measured values read sequentially from the receiving areas with stored desired values and from them generates signals, for example, for a microscope arrangement and/or—if deviations have been determined—for correcting signals for a relocation device by means of…