Method for optimizing the image properties of at least two optical elements as well as methods for optimizing the image properties of at least three optical elements

US6678240B2 · kind B2 · utility

Assignee

• Carl Zeiss SMT GmbH · DE

Inventors

• Bernd Geh · Scottsdale, US
• Paul Graupner · Aalen, DE
• Klaus Wurmbrand · Ettlingen, DE
• Thomas Stammler · Aalen, DE
• Dirk Stenkamp · Oberkochen, DE
• Jochen Stuhler · Aalen, DE

Key dates

• Filing date: Sep 19, 2002
• Grant date: Jan 13, 2004
• Expiry date: Sep 19, 2022

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70666
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

In order to optimize the image properties of several optical elements of which at least one is moved relative to at least one stationary optical element, the overall image defect resulting from the interaction of all optical elements is first of all measured. This is represented as a linear combination of the base functions of an orthogonal function set. The movable element is then moved to a new measurement position and the overall image defect is measured once again. After the linear combination representation of the new overall image defect, the image defects of the movable element and of the stationary element are calculated from the data thereby obtained. With only one movable optical element a target position in which the overall image defect is minimized can be directly calculated and adjusted there from. If several movable optical elements are available, methods are given for the efficient determination of the respective target position.