Abstract: To protect the optical surface of optical disc information recording media such as a compact disc (CD) or a digital versatile disc (DVD), that surface is coated with a removable layer of a material that does not significantly alter the optical properties of the disc. Whenever the coating layer may have become damaged, it is removed and replaced with a new layer.

Abstract: Methods for bonding structurally asymmetrical or otherwise structurally dissimilar optical discs are provided. A bonded optical disc stack is formed from a first and a second optical disc by coating the back side of at least one of the optical discs with a light-curable bonding material and stacking the first and second optical discs back to back. The front side of the second optical disc is exposed to light for a first predetermined time period. The front sides of both the first and second optical discs are then exposed to light for a second predetermined time period. Finally, the front side of the first optical disc is exposed to light for a third predetermined time period. In this manner, when the second optical disc comprises program information and the first optical disc comprises a graphical image or other artwork, image pass-through due to simultaneous exposure and disc warpage due to one-sided exposure are significantly reduced.

Abstract: A container for an optical disc such as a compact disc (CD) or digital versatile disc (DVD) has a bottom structure, a top structure movable relative to the bottom structure, and a hub structure projecting up from the bottom structure. With the lid open, the central aperture of the disc is easily placed on or removed from the hub. In this condition the hub structure centers the disc in the bottom of the container but does not retain the disc in the container. When the lid is closed, however, the lid causes the hub structure to radially enlarge and secure the disc. Reopening the lid allows the hub to return to the condition in which it does not retain the disc.

Abstract: A system using free ranging automatic guided vehicles (AGVs) for loading and unloading material from a number of trailers is provided. The system employs a plurality of sensors for monitoring both pedestrian, operator driven vehicles and other AGV traffic, and for ensuring that the trailers are parked in position and ready for loading and unloading. The system further includes signals for controlling traffic and a plurality of trailer mounted targets for AGV navigation. During an operation cycle full containers are unloaded from a first trailer and empty containers are loaded on a second trailer.

Abstract: A method for continuous injection molding of thermoplastic materiall into three-dimensional sheets having a projection extending from a substantially uniform backing layer. An extrusion die having a face matching the surface of a rotatable mold drum with cavities therein provides molten thermoplastic material simultaneously into the cavities to form the projections and onto the surface to form the backing layer.