1 optical ZnSe/CaF2 window
2 diamter:20mm
3 size tolerance:+/-0.01mm
4 large optical window
5 optical glass window

optical lens  Calcium Fluoride Window

High Precision Dimension
Minimal Transmitted Beam Deviation
Excellent Environmental Durability
Applications
Projection Optics System
Imaging Optics System
Optical Measurement Systems
Specifications
Material  Calcium Fluoride
Diameter Tolerance: +0.0, -0.1 
Thickness Tolerance:+/-0.2 
Parallelism <1 arc minutes   
Surface Quality:80-50
Bevel   0.25mm×45 ° 
Clear Aperture    >85% 
Coating   Specified by customer