A fuze for detecting an obstacle in proximity, an obstacle in proximity defined as being an obstacle exhibiting a minimum distance from the fuze, wherein the fuze comprises at least: an emission device emitting a light beam directed forward of the fuze; a reception device detecting the luminous fluxes in a cone directed forward of the fuze, the light beam and the cone having relative orientations such that they cross one another; a detection volume being the volume where the light beam crosses the cone so that when an obstacle is in the detection volume, the light emitted by the emission device is backscattered toward the detection device, an obstacle in proximity being detected by detecting the maximum of backscattered power, the reception cone is centered on the axis of the fuze.