The device has a lighting module (1) in which light sources (2) e.g. LEDs are arranged. Control units (3) individually controls intensity of the light sources. The control units are configured so that a lighted field (4) takes a full circular form, whose focalization diameter varies by selective control of the sources at constant luminous power. An optical element is arranged between the sources and a zone to be lighted, where the element includes a diopter (5a) that is plane and oriented towards the zone to be lighted.
