US Patent Issued to Carl Zeiss SMT on June 30 for "Imaging optical unit" (German Inventors)

ALEXANDRIA, Va., July 16 -- United States Patent no. 12,669,755, issued on June 30, was assigned to Carl Zeiss SMT GmbH (Oberkochen, Germany).

"Imaging optical unit" was invented by Hans-Jurgen Rostalski (Furstenwalde/Spree, Germany), Holger Munz (Aalen, Germany) and Christoph Menke (Oberkochen, Germany).

According to the abstract* released by the U.S. Patent & Trademark Office: "An imaging optical unit comprises a plurality of mirrors for imaging an object field into an image field. The imaging optical unit has an image-side numerical aperture greater than 0.55. Each mirror is configured so that it can be measured by a testing optical unit having at least one DOE with a predetermined maximum diameter for test wavefront generation. For th...