
4.1
Sampling Using an Array of Points
77
1/1?!
I
sinö. Similarly, vv
2
is perpendicular to r, and its magnitude is equal to
l/|r
2
|
sin0.
The reciprocal basis vectors vv, and vv
2
define a reciprocal lattice in the
w^-plane. The reciprocal lattice is a periodic arrangement of points in the
wy-plane, where the points are defined by the position vectors w
mn
given by
Figures 2c and 2d are reciprocal lattices for the sampling lattices in Figs. 2a
and 2b, respectively.
4.1.3 Sampling of Pictures Using a Sampling Lattice
We will now extend the preceding theory to two-dimensional functions
defined over the xy-plane. We assume that these functions ar