2. MATHEMATICAL MODEL
The three line opto-electronic camera contains in the focal plane of
an objective three linear sensor arrays a, b, c which are oriented per-
pendicularly to the direction of flight (/4/). During the flight with-
in each read cycle one image is recorded, consisting of only three
lines. Generally each object point is projected into three images per
flight strip, the points at the beginning and at the end of a strip are
projected only into two images. If blocks with 20% or 60% sideward
overlap are used, object points are projected into as many as six or
nine images.
Figure 1 represents the geometry of the imaging process. For the object
points Pi (i=1...n), projected onto the linear sensor arrays aj, bj or
ci in the images Ij (jsl...m) the (non integer) read cycle numbers dj
of the images Ij and the (non integer) pixel numbers ai,j» bi,j or cí,j
of the image points Pi,j in the linear arrays aj, bj or cj are deter-
mined by an operator or by digital correlation. The corresponding image
coordinates xi,j» Yi,J are derived from aij; bij Or Cij and the cali-
brated location of the linear sensor arrays in the focal plane (in-
terior orientation). :
orientation image image r orientation image
| sensor b Ike : j sensor c
qoem» -—— ammo x
# + *
1 !
iati
HE ; kelcu
: j | >
d d d T
k J kel read cycle number
2
Py
: "n
X
- Figure 1 -
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