FLUORESCENT MULTILAYER DATA STORAGE WITH HIGH CAPACITY AND HIGH DATA RATE

In an optical medium such as a fluorescent multilayer disk (206), both reading speed and storage capacity are increased in various ways. Multiple heads (103) can be provided, in which case one head reads information while another moves from one reading position to the next. An optical head can read from several tracks on a disk simultaneously by focusing the exiting light into a light strip and using a photo-sensor array (210). The information pages in each layer can be staggered from those in adjacent layers. The number of layers in a medium can be selected by maximizing capacity with respect to numerical aperture. To increase exposure time, a reading head can follow the medium for one reading operation and then return to its initial position for the next reading operation. In an optical medium such as a fluorescent multilayer disk (FMD), both reading speed and storage capacity are increased in various ways. Multiple heads can be provided, in which case one head reads information while another moves from one reading position to the next. An optical head can read from several tracks on a disk simultaneously by focusing the exiting light into a light strip and using a photo-sensor array. The information pages in each layer can be staggered from those in adjacent layers, and the rotation speed can be set accordingly. The tracks on a disk can extend radially. The number of layers in a medium can be selected by maximizing capacity with respect to numerical aperture. To increase exposure time, a reading head can follow the medium for one reading operation and then return to its initial position for the next reading operation. La présente invention concerne un support optique tel qu'un disque à couches multiples fluorescentes (fluorescent multilayer disk / FMD), dans lequel à la fois la vitesse de lecture et la capacité de stockage sont améliorés de différentes manières. L'invention fait intervenir de multiples têtes, l'une des têtes lisant les informations alors qu'une autres se déplace d'une position de lecture à l'autre. Une tête optique peut lire simultanément plusieurs pistes sur un disque par focalisation de la lumière de sortie en une bande lumineuse et par utilisation d'un réseau de capteurs lumineux. Les pages d'informations de chaque couche peuvent être échelonnées à partir de celles des couches adjacentes, et la vitesse de rotation peut être fixée en conséquence. Les pistes peuvent être disposées de façon radiale sur un disque. Le nombre de couche d'u