Index of refraction

λ (μm)

T_designed (μm)

T_Parabolic

$n=1.5$

4

1.00

0.9962

$n=1.5$

7

0.9999

0.9962

$n=1.5$

9

0.9998

0.9962

$n=2.5$

4

0.9995

0.9834

$n=2.5$

7

0.9995

0.9834

$n=2.5$

9

0.9949

0.9834

$n=3.5$

4

0.9911

0.9677

$n=3.5$

7

0.9911

0.9676

$n=3.5$

9

0.9911

0.9677