| 摘要 |
A method for determining authenticity of an optical medium comprising modifying the optical medium, the optical medium including a first layer adjacent a data layer, the modifying the optical medium comprising selecting a region of the data layer to be distorted and prior to a reading operation of the medium, distorting the region of the data layer, the distorted region extending in a direction along a track of the data layer; performing a reading operation of the optical medium, the distorted region modifying the reading operation of data stored in the data layer corresponding to the distorted region, such that when data stored in the data layer corresponding to the distorted region is read, a measurable change in system performance of the reading operation results and the ability to perform the reading operation in the distorted region is maintained, the distorted region maintaining its optical characteristics following irradiation of the distorted region during the reading operation; detecting the measurable change in system performance; and authenticating the optical medium based on the measurable change in the system performance. |
