Intrinsic resolving power of XUV diffraction gratings measured with Fizeau interferometry

TL;DR

This paper presents a Fizeau interferometry method to accurately measure the intrinsic resolving power of XUV diffraction gratings, surpassing traditional techniques in sensitivity to phase errors, demonstrated with a resolution of 50,400.

Contribution

The paper introduces a novel interferometry-based measurement technique for diffraction grating resolution, improving accuracy over existing methods.

Findings

Achieved a resolving power of 50,400 for an XUV diffraction grating.

Demonstrated the method's sensitivity to long-distance phase errors.

Showed superiority over traditional long-trace profiler techniques.

Abstract

We introduce a method for using Fizeau interferometry to measure the intrinsic resolving power of a diffraction grating. This method is more accurate than traditional techniques based on a long-trace profiler (LTP), since it is sensitive to long-distance phase errors not revealed by a d-spacing map. We demonstrate 50,400 resolving power for a mechanically ruled XUV grating from Inprentus, Inc.