An optical shear sensor that includes a first and second outer surface at opposing sides and a sensing element is disclosed. In one aspect, the sensing element has an optoelectronic source for emitting light of a predetermined wavelength and having a source front surface where light exits the optoelectronic source, and a photodetector for detecting light of the predetermined wavelength and having a detector front surface where light of the optoelectronic source is received. The optoelectronic source is positioned along the first outer surface and emits light towards the second outer surface. A flexible sensing layer transparent to the predetermined wavelength covers the front surface of the optoelectronic source and the front surface of the photodetector. Upon application of a shear stress, the sensing layer deforms elastically and the outer surfaces are displaced along directions parallel to each other and the source front surface so the intensity of light detected by the photodetector changes.