We have built a fibre optic force microscope scan head which scans the
cantilever relative to a fixed sample. The design enables the fibre-t
o-cantilever distance to be altered by moving the fibre relative to th
e fixed cantilever. This design feature is particularly important when
using the variable deflection mode and for acquiring force versus dis
tance curves. Our interferometer system currently reaches a resolution
of 0.01 nm (peak-to-peak).