A lighting device, such as a LED module, comprising an elongated support structure having a longitudinal direction and electrically-powered light radiation sources distributed along the support structure, the support structure including at least one light-permeable layer, one or more optical signal sources coupled with the light-permeable layer, for injecting therein an optical signal propagating in the longitudinal direction, and one or more optical signal detectors coupled with the light-permeable layer, for detecting the optical signal injected by the optical signal source(s).