Technique for vacuum ultraviolet image dissection

Image evaluation for optical components in the vacuum ultraviolet (VUV) having subarcsecond resolution has been developed at the Goddard Space Flight Center's Diffraction Grating Evaluation Facility (DGEF)1 using raster scan image dissection. A microscopic, rectangular aperture2 is discretely positioned along scan lines throughout an image area and the light passing through it is detected to build up an image irradiance map. The technique simulates a "one pixel at a time," VUV-sensitive, photon counting, area array detector with high dynamic range and pixel sizes down to below 2 um. Image statistics provide encircled energy and angular resolution profiles for imaging systems in the VUV. Comparisons of raytrace data and experimentally obtained images are presented.