Abstract: The invention relates to a photonic integrated circuit including a substrate (1) comprising at least one optical circuit (4) and means for interconnecting (2, 3) the optical circuit with at least one opto-electronic component (6, 8, 9, 11, 12) added on to the substrate. The interconnection means are constituted by at least one zone of the substrate with the refractive index thereof being modified to provide said interconnection. This zone of the substrate includes at least one graded index lens.