Abstract: A differential pressure sensor includes a containment body including internally a wall creating first and second cavities, a piston slidingly housed in the first cavity and including a magnet mounted on a first axial end thereof, proximal to the wall and a magnetic sensor housed in the second cavity, near the wall for measuring the axial distance of the magnet from the wall and generating a signal representing such distance. The pressure sensor further includes a lighting element for emitting light radiation, a control circuit operatively interposed between the magnetic sensor and the lighting element and configured for varying the light radiation emitted by the lighting element as a function of a variation in the representative signal generated by the magnetic sensor. An interface element includes a radiant surface facing outwards from the body and an optical guide, extending between the lighting element and the radiant surface.