Photovoltaic cell having a coloured appearance particularly for a watch dial

There is described a coloured photovoltaic cell (1) with a semiconductor, preferably silicon, which has high efficiency and a pleasing coloured appearance, allowing it to be used as a dial for a watch or another electronic apparatus powered by the cell. The cell includes a reflective metal substrate (2) serving as the bottom electrode, a stack of hydrogenated amorphous silicon layers forming p-i-n junctions (8), and a transparent top electrode (9). The latter may be coated with a layer (16) of slightly diffusing lacquer, which may be colourless or coloured. The respective thicknesses e1 of the top electrode and e2 of the silicon are combined as a function of the refractive Indices of the materials so as to produce an interferential reflection in a predetermined reflection spectrum.