Methods and apparatus for both coarsely and accurately controlling a scanning
stage are disclosed. According to one aspect of the present invention, an apparatus
for scanning an object includes a first stage that is coupled to a first actuator
which moves the first stage along an axis, as well as a second stage that is arranged
to accommodate the object. A first coupler which has first and second ends is aligned
along the axis such that the first and second ends of the first coupler contact
the first and second stages, respectively. A second coupler which also has first
and second ends is aligned along the axis such that the first and second ends of
the second coupler contact the first and second stages, respectively. When the
first stage scans in a first direction, the first coupler causes the second stage
to scan along the axis through the first coupler.