A photovoltaic device which includes: a) a substrate based on a crystalline semi-conductor material; b) a first electrode which includes at least one heterojunction made on one face, referred to as the rear face, of the substrate, where this heterojunction includes a layer based on a doped amorphous semi-conductor material; and c) a second electrode. The phosphor powders have a small particle size, narrow particle size distribution and are substantially spherical. The presence of this selective silicidation creates a beneficial low-resistance connection between the N+ region of the polysilicon line and the P+ region of the polysilicon line. The second two-link hinge unit is provided between the base unit and the supporting unit for allowing revolution of the display device around an imaginary axis defined in a horizontal direction of display device.