ES # 120: 78-83% Reflectance @ 121.6nm

                 ES # 160: 84% - 86% Reflectance @ 160.8nm

                ES # 190:  >= 88% Reflectance @ 190-195nm

             ES # 200: >= 88% - 90% Reflectance @ 200nm

All eSource Optics VUV-UV Mirrors are measured on a Vacuum Spectrophotometer system capable of measuring VUV reflectance as short as 120nm. The system is based on a calibrated Model VM-502 0.2 Meter Vacuum Monochromator with VUV enhanced 1200g/mm grating & Deuterium light source for very accurate UV to VUV  wavelength measurements.