Interfaz visual para un Autocolimador Nikon 6D mediante procesamiento de imágenes con precisión sub-píxel: un caso de estudio

The goal of this paper is to describe the potential of a ba- sic visual interfase applied to a Nikon 6B/6D autocollimator in order to replace human operator within a “laboratory grade” measurement. The implemented optical interface consists of a CMOS sensor-based camera attached to the autocollimator ocu- lar, camera positioning devices and a proprietary digital image processing package, built around Matlab OR environment, used to analyze the reticle's image to detect both the scale and the measuring cross at sub-pixel level. In a controlled experiment the system performance was compared against an electronic le- vel with internationally traceable certification. Pitch angles we- re obtained with a resolution three times better than the original of the instrument. This example shows that the value of 0,06 pixels for the uncertainty associated with sub-pixel position of the reticle lines is realistic, allowing to continue working on a robust interface for all angle parameters that can be measured using an autocollimator.