Schott Sk11, 313nm - 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	1.17963631E+00;
B2	2.29817295E-01;
B3	9.35789652E-01;
C1	6.80282081E-03;
C2	2.19737205E-02;
C3	1.01513232E+02;