Light sectioning with large depth and high resolution.

We report a method for 3-D sensing by light sectioning. The specific goal is to demonstrate that high resolution and large depth can be achieved simultaneously, thus overcoming the major limitation of conventional light sectioning. We use the diffraction pattern of an axicon to generate a light knife with large depth of field (for example, 1700 mm) and high lateral resolution (for example, 55 microm). Illuminating an object with this light knife creates a profile on the object. We detect this profile with a CCD TV camera and evaluate the centroid of the profile by means of an interpolation algorithm.