Optical displacement transducer, displacement measurement system and method for displacement detection therefrom

An optical displacement transducer includes a transducing element (10) comprising at least a first (11; 51; 71) optical fiber, having a first end face (13) substantially aligned along an axis (15; 55; 75) and positioned with a small gap (16; 56; 76) between said first end face (13) and a second end face (14; 61) of a reception assembly (e.g. a second optical fiber) (12,14; 61,62,52; 61,63,72), the transducer (20) further comprising at least a light source (21) coupled for transmission to the first optical fiber (11) and at least a photo-detector (22) coupled for reception to the second optical fiber (12). The first end face (13) and second end face (14; 61) are displaceable along the axis (15; 55; 75) and relatively with respect to each other, in order to follow the displacement (d) of points associated to the first end fac The transducer is effective in detecting axial displacement simply and at low cost.