15) to the first
interface ABC, we get
1
2
2
1
1
1
OB
BI
BC
n
n
n
−n
+
=
(9 17)
A similar procedure applied to the second
interface* ADC gives,
2
1
2
1
1
2
DI
DI
DC
n
n
n
−n
−
+
=
(9 18)
For a thin lens, BI1 = DI1 Adding
Eqs