Abstract: Diffraction inhibition with highly localized electromangnetic energy can be achieved with all angle self-collimation of photonic crystal.In this paper,we calculate and analyze the equi-frequency contours of photonic crystals with plane wave expansion method.The diffraction inhibition effect is achieved experimentally.A propagation length of 0.4mm is observed experimentally with our CCD camera with wavelength ranging from 1540nm to 1570nm.The propagation loss is calculated to be 17dB/mm by sampling the scattering light form the rods of the structure.The broadband property our structure exhibits and the millimeter scale propagation length make it possible for on-chip optical interconnection.