Type: Custom Optical Window 
Material: VUV Grade MgF2
Form: Single Crystal
Diameter: 25.0 +/-0.1mm 
Thickness: 1.0 +/-0.1mm
Orientation: Random (C-Axis perpendicular best-efforts)
SQ: S/D 60/40 both sides
Flatness: < 4 fringes/inch over CA 90% @ 633nm.
Parallelism: ≤ 4 arc minutes
Clear Aperture: ≥ central 90% 

                                                

                                                   
         eSource Optics / PMB 126, 1225 Providence Rd, Whitinsville, MA 01588

       VUV-UV Optical Filters & Mirrors/ VUV-UV Windows/Lenses & Prisms