Write strategy

Abstract: The invention relates to a method and recording device for selecting an optimal write strategy for a specific type of optical recording disk. Such an optimal write strategy is selected even when the optical recording disk is of a type that has not been previously encountered or when the optical recording disk is otherwise unrecognized by an optical disk drive. The optimal write strategy and associated settings are selected from a set of write strategies stored in a disk drive. The disk drive bases its selection of the write strategy on the performance results of test writings conducted on the optical disk. The method entails testing the write strategies first at the maximum possible write speed and if necessary, at successively lower speeds until a write strategy that achieves a minimum acceptable write quality is identified or until the minimum write speed is reached. The selected optimal write strategy may be stored in the recording device or, alternatively, on the optical recording disk itself.

Abstract: The present invention provides a method of recording control information in a recordable optical disc including at least one recording layer. In recording control information within a management area of an optical disc including at least one or more recording layers, the present invention includes providing the control information to each of the at least one or more recording layers per recording velocity, recording an information identifying a type of the corresponding control information within the control information, and recording a write strategy (WS) interworking with the type of the control information. In recording a write strategy (WS) within disc information, CLV and CAV are separately recorded, whereby it is able to efficiently cope with the record/playback of the optical disc.

Abstract: In a recordable optical disc apparatus, the efficiency of the work necessary for optimizing the write pulse condition (write strategy) is improved and the read compatibility among drive units is ensured by a minimum addition of circuitry. An edge shift amount or a read signal and a binarized result are stored in an external memory as digital data and are later processed by analysis software in a host PC. The write pulse shape and power conditions can be optimized to individual optical disc media in a short time by means of a simple circuit. Further, by optimizing the write pulse shape and power condition in view of the PRML class or the difference in NA of the head, any deterioration of read compatibility can be avoided.

Abstract: We have developed an inorganic write-once disc based of the Blu-ray disc format. Our write-once disc has a double layer recording stack of a Cu alloy layer and a Si layer. These materials are environmentally friendly and low in cost. We designed a new write pulse strategy for high-speed recording while maintaining low recording peak power. As a result of using our write strategy, we obtained a jitter value of less than 8% with optimum recording power of 5 mW in the range of 36 Mbps to 144 Mbps.