
MATRIX OPTICS 69
3.2.2 Imaging
Because the matrix from H to H
is a thin-lens matrix, we know that the equations we developed
for the thin lens will be valid for any arbitrary lens system provided that we measure distances
from the principal planes. Therefore let us consider two more translations: one from the object,
S, to the front principal plane, H, and one from the back principal plane, H
, to the object, S
.
Then, looking back at Figure 3.6, the imaging matrix is
M
SS
= M
H
S
M
HH
M
SH
= T
s
M
HH
T
s
. (3.44)
We want to nd an equation relating s and s
such that this matrix describes an imaging system,
but what are the constraints on an imaging matrix?