  A method for determining the positions of hologram dislocations relative to
the optical axes of entangled Laguerre Gaussian modes is proposed. In our
method, the coincidence count rate distribution was obtained by scanning the
position of one of the holograms in two dimensions. Then, the relative position
of the hologram dislocation was determined quantitatively from the positions of
the minimum and maximum coincidence count rates. The validity of the method was
experimentally verified, and in addition, an experiment demonstrating the
violation of the Clauser-Horne-Shimony-Holt inequality was performed using the
well-identified optical axes of the entangled modes.
