The optical near-field technique is applied to provide a direct experimental observation of the refracted beam propagation inside a photonic crystal structure displaying a superprism effect. The obtained results show a $35°$ light beam angle deviation for a wavelength variation from 1500 to $1600\mathrm{nm}$ . The experimentally determined beam divergence is in good agreement with modeling predictions and previously performed transmittance experiments. A marked self-collimation propagation over a broad $20\mathrm{nm}$ wide spectral range centered at $\lambda =1550\mathrm{nm}$ is experimentally demonstrated. The developed technique opens promising perspectives for the invisibility cloaking structures investigation.