A digitizing controller which acquires sequentially position data while profiling the shape of a model and outputs them as NC data. A tracer head (3) is provided with two non-contact distance finders (30a, 30b) for measuring independently the distances to the model surface in parallel with each other in a feeding direction. A sampling circuit (16) samples the values measured by the non-contact distance finders (30a, 30b) every predetermined sampling time. The value measured by the non-contact distance finder (30a) and the value measured by the distance finder (30b) sampled at the previous sampling time are stored in memory means (13). Data of the model surface (4) in the normal direction is determined on the basis of at least three measured values among the values measured by the distance finder (30a) and those by the non-contact distance finder (30b) sampled at the time of this sampling. In this manner, high accuracy data in the normal direction can be obtained at a high speed. This normal direction data is utilized for the calculation of an offset quantity of a tool, and the like.