According to examples of the presently disclosed subject an active triangulation system includes an active triangulation setup and a calibration module. The active triangulation setup includes a projector and a sensor. The projector is configured to project a structured light pattern that includes a repeating structure of a plurality of unique feature types and a plurality of markers distributed in the projected structured light pattern, where an epipolar distance between any two epipolar lines which are associated with an appearance in the image of any two respective markers is greater than a distance between any two distinguishable epipolar lines. The sensor is configured to capture an image of a reflected portion of the projected structured light. The calibration module is configured to determine an epipolar field for the active triangulation setup according to locations of the markers in the image, and to calibrate the active triangulation setup.