Schott Sk8, 334nm - 2325nm
USER
2 1
SQRT(1+B1*wvl^2/(wvl^2-C1)+B2*wvl^2/(wvl^2-C2)+B3*wvl^2/(wvl^2-C3))
0
B1	1.29821149E+00;
B2	2.52817469E-01;
B3	9.77516703E-01;
C1	7.22506070E-03;
C2	2.55622691E-02;
C3	1.08370884E+02;