1.Material : BK7
a.Sides S1 ,S2 to be polished , other sides to be grinded .
b.The areas with grid are effective coverages of S1 and S2.
d: Surface quality : 20-10 in effective coverages
4.Coating :BBAR broadband antireflection coating for sides S1 and S2 ; ARR<0.2% @790nm-990nm .