Optical type touch screen

摘要

The present invention relates to an optical type touch screen including a transparent plate 1 of generally polygonal shape having at least three angles, limited by an edge against which are locally arranged photodetectors 12 sensitive to the radiation transmitted by the waveguide-forming plate. The photodetectors 12 include at least one photodetector arranged at each of the angles of the polygonal shape oriented against the edge along the bisector to the sides of an angle in question, in such a way that the axis of a field of detection of the said photodetector is oriented substantially along the bisector of the said angle. <IMAGE>