Abstract: The invention is directed to an optically marked surface. In the preferred embodiment, the optically marked surface (15) comprises a light source (16), a surface to be marked (18), optical material (19) capable of illumination by the light source, the optical material, the surface and the light source being so configured and arranged that illumination of the optical material is visible on the surface. The present invention also discloses turf comprising artificial or natural turf fibers and fiber optic filaments extending between the turf fibers. The present invention also provides a method of marking a surface comprising the steps of providing a light source, providing a surface to be marked, providing an optical material capable of illumination by the light source, configuring and arranging the optical material, the surface, and the light source such that illumination of the optical material is visible on the surface, and illuminating the optical material.

Abstract: The invention is directed to an optically marked surface. In the preferred embodiment, the optically marked surface (15) comprises a light source (16), a surface to be marked (18), optical material (19) capable of illumination by the light source, the optical material, the surface and the light source being so configured and arranged that illumination of the optical material is visible on the surface. The present invention also discloses turf comprising artificial or natural turf fibers and fiber optic filaments extending between the turf fibers. The present invention also provides a method of marking a surface comprising the steps of providing a light source, providing a surface to be marked, providing an optical material capable of illumination by the light source, configuring and arranging the optical material, the surface, and the light source such that illumination of the optical material is visible on the surface, and illuminating the optical material.