Windows are used to allow optical radiation to pass from one environment to another without

allowing other elements of these environments to mix. And it does not change the wavelength

distribution of the beam, the transmitted wavefront nor does it scatter any of the light out

of the beam.

Typical Specifications:
 
Material: fused silica 
Tolerance: +/-0.10mm
Parallelism: 3 minutes
Surface quality: 60-40 scratch and dig
Flatness: lambda/4
Coating: with or without AR coating
 
Other material such as Germanium, Silicon, CaF2 … is available upon request.