  We propose a scanning tunneling microscopy Aharonov-Bohm (AB) interferometer
on the surface of a topological insulator (TI) to probe the crossover from
analogous weak antilocalization (WAL) to weak localization (WL) phenomenon via
the AB oscillations in spin-resolved local density of states (LDOS). Based on
our analytical and numerical results, we show that with increasing the energy
gap of TI surface states, the $\Phi_{0}/2$=$hc/2e$ periodic AB oscillations in
spin-resolved LDOS gradually transit into the $\Phi_{0}$ periodic oscillations.
