Schott LaK N13, 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	1.25792373E+00;
B2	5.53402861E-01;
B3	1.06335742E+00;
C1	6.21494710E-03;
C2	2.16809853E-02;
C3	1.04494099E+02;