Abstract: To provide theoretical and technical methods for recognizing encoded pattern and achieving 3D multi-spot surface profiling, measure 3D coordinates and reconstruct the surface profile of an object, the encoded pattern with three gray levels and the new decoding algorithm were used to solve the correspondence problem and the geometric method of coordinate transformation was used to calculate 3D coordinates. The encoded pattern was recognized successfully and the formula for range data was deduced. 3D coordinates were attained and the profile was reconstructed. This method has the advantages of simple operation, fast acquirement of data and easy implementation.