A nondestructive technique that provides near-field measurements as well as refractive index profiles and geometry of waveguides in LiNbO3 within a few minutes is demonstrated. It is a modification of the refracted-near-field (RNF) method well known for optical fiber characterization. Spatial resolution below 1 μm is achieved. The index resolution is about 2 x 10-4, the reproducibility better than 7%. A new calibration method for RNF measurement is introduced.