Calcium Fluoride (CaF2) Wedged Windows is a protective window used in laser applications to eliminate feedback and standard grating stripes, it's key feature lies in the fact that the two surfaces are not parallel, nad it has a small wedge angle.Usually 30 arcmin(0.5°) to balance the beam deflection and control, if the wedge angle larger, which result in more significant beam deviation, but may interfere with delicate optical path.
CaF2 Wedged windows provide laser output protection from environmental effects and are ideal for beam sampling applications
CaF2 window VS Fused Silica Window
Features
CaF2 window
Fused silica window
Spectrum
0.18-8um covering UV-VIS-MWIR
0.19-2.5um covering UV-VIS-NIR
Thermal performance
high thermal expansion coefficient, prone to thermal cracking,and extreme temperature changes should be avoided
good thermal stability, low thermal expansion, resistant to thermal shock
Mechanical hardness
relatively soft prone to scratches, operation requires…