Patent ID: 7667859

Claim:
A method for detecting a contrast edge having a light transition zone which is substantially rectilinear in a given direction and separating two regions of differing luminance, comprising the steps of: providing a device wherein the device including: at least an assembly formed by a first optical sensor and a second optical sensor having a total angle of vision delimited by an average direction of observation of the first optical sensor and the second optical sensor, and a lens having an optical centre intercalated between the assembly and the light transition zone, the first optical sensor and the second optical sensor being placed substantially in an image focal pane of the lens; carrying out, in another direction transverse to the given direction, periodic positional scanning of the total angle of vision of the first optical sensor and the second optical sensor by relative translation of the assembly in this other direction, a law of periodic scanning corresponding to non-uniform scanning for at least a portion of each period of periodic scanning, the total angle of vision being delimited by the average direction of observation of the first optical sensor and the second optical sensor; measuring, on a basis of signals delivered by the first optical sensor and the second optical sensor, a time difference which depends on an angular position of the light transition zone, relative to a reference direction contained in the total angle of vision, based on the scanning law, the reference direction being linked to a specific value of the time difference.