With the improvement of fabrication techniques, the nanophotonics and more especially the photonics crystals which are periodic structure at the Wavelength scale have been recently developed. In this work, by using a scanning near-field optical microscope, we study such components. Firslty, we use the local probe to visualize the light distribution inside photonic crystal microcavities etched into semiconductor III/V. We focus us on the explanation of the near-field maps formation and on the probe influence on these maps. Thus, we have visualize degeneracy splitting of optical cavity modes and clearly observed in near-field cavity modes which were not visible in far-field. Moreover, in the case of Bloch mode cavities, we have also experimen...