Structures and processes for controlling access to optical media

Abstract

An optical disc is provided with an associated optical shutter. In a first state, the optical media interferes with the ability of an interrogating laser beam to read data from the optical media, and in a second state, the optical media is substantially transparent, enabling the laser beam to read the disc. A powering circuit is used to cause the optical shutter to transition from a first state to the second state. In one example, an integrated circuit acts as the powering circuit, as well as providing logic and processing functions. The integrated circuit also couples to an RF antenna, enabling the integrated circuit to communicate with an associated RF scanning device. The optical shutter may take various geometric shapes, and typically has an electrochromic material for facilitating state change. The electrochromic material may fill the shutter, or the material may form a pattern. The shutter may be positioned on the disk so that transition edge-effects are reduced, allowing for reduced interference with the laser beam when the optical shutter is in its clear state. The optical shutter does not cover the entire data area of the disc, and in one example, the optical shutter is quite small, allowing for lower cost production, as well as reducing power requirements to transition the electrochromic material. Power requirements may be further reduced by forming the electrochromic in a pattern. A small optical shutter may disable reading of disc, for example, by placing the small shutter over an important section of the disc, such as the lead-in area.

Dependencies are inferred from the claim text.