Schott Sk55, 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	1.15265225E+00;
B2	4.32145290E-01;
B3	1.03215169E+00;
C1	5.82679114E-03;
C2	1.90244615E-02;
C3	8.81750460E+01;