Schott LaF 20, 365nm - 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	1.65107169E+00;
B2	1.18474934E-01;
B3	1.11548729E+00;
C1	9.70502320E-03;
C2	4.28927477E-02;
C3	1.14057600E+02;