1. An optical detection method of determining the position of an object in a particular detection area of a surface, the method comprising: a preliminary step of disposing in the vicinity of said detection area and on the same side thereof relative to the object at least three elements including at least one emitter of light and at least one receiver of light adapted to cover the detection area, each emitter being adapted to emit light in such a way that it does not hit said surface in the detection area, the method further comprises: a step during which one of said receiver measures the quantity of light reflected by the object when the object is illuminated by one of said emitter for at least two different emitter—receiver pairs, a step of calculating at least two characteristic values from said measured values, and a step of determining at least one position of the object by directly reading a table indexed by said at least two characteristic values, the content of said table being predetermined and set before said measurement step.