The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 09, 2004
Filed:
Jul. 05, 2002
Ulrich Kaczynski, Bad Nauheim, DE;
Klaus Rinn, Heuchelheim, DE;
Leica Microsystems Semiconductor GmbH, Wetzlar, DE;
Abstract
The present invention concerns an interferometric measurement apparatus for wavelength calibration, having a laser light source ( ), a detector ( ), and an interferometer ( ), the laser light source ( ) emitting light of at least one wavelength, the interferometer ( ) separating the light of the laser light source ( ) into two sub-beams ( )—a reference beam ( ) and a measurement beam ( )—and combining the sub-beams ( ) again after at least one reflection at one reflection means ( ) each, and the path length difference between the reference beam ( ) and measurement beam ( ) defining a constant wavelength calibration distance. In order to increase the measurement accuracy and reduce measurement errors, the measurement beam distance can be extended, but without causing problems in terms of manufacture, assembly, and/or alignment. The interferometric measurement apparatus according to the present invention is characterized in that at least one additional reflection means ( ), which reflects the measurement beam ( ) at least largely in the opposite direction, is provided in the beam path of the measurement beam ( ).