A textured transparent panel placed near an element capable of collecting or emitting light. The panel is textured on at least one of its faces by a plurality of geometrical features in relief, such as pyramids or cones. The panel, which may be made of glass, provides excellent light transmission for all light orientations. The panel may be combined with a photoelectric cell, especially one made of polycrystalline silicon, and may also act as a light diffuser, especially for liquid-crystal screens or plasma lamps.