Abstract: A method for writing a multi-session recordable disc. The method includes performing an immediate optimum power calibration (IOPC) in the lead-in area of each session of a multi-session recordable disc, determining a recording power for the session according to the IOPC output, and completing the session using the determined recording power. The method may be used in addition to the optimal power calibration (OPC) procedures included in the normal initialization of recordable discs. IOPC provides recording devices with an optimal recording power value obtained closer to the point of use than that obtained by conventional OPC procedures carried out at the extremities of the recordable area. Alternative embodiments of the method make accommodations for recording power variations according to disc velocity mode (CAV/CLV), recording speed, and the basis of the IOPC upon a variety of available data sources.

Abstract: A recorder including an optical pick up head and a processor can provide a number of recording speeds for recording an optical disc. The optical pick up head is for recording the optical disc while the processor for controlling the optical pick up head to perform an optimum power calibration (OPC) procedure for each recording speed to provide the corresponding recording quality index. A method of selecting recording speed includes placing the optical disc into the recorder; performing the OPC procedure for each recording speed in the recorder to obtain the corresponding recording quality index; and selecting the required recording speed from the supported recording speeds according to the recording quality indexes and records the optical disc according to the selected recording speed.

Abstract: A method for writing a multi-session recordable disc. The method includes performing an immediate optimum power calibration (IOPC) in the lead-in area of each session of a multi-session recordable disc, determining a recording power for the session according to the IOPC output, and completing the session using the determined recording power. The method may be used in addition to the optimal power calibration (OPC) procedures included in the normal initialization of recordable discs. IOPC provides recording devices with an optimal recording power value obtained closer to the point of use than that obtained by conventional OPC procedures carried out at the extremities of the recordable area. Alternative embodiments of the method make accommodations for recording power variations according to disc velocity mode (CAV/CLV), recording speed, and the basis of the IOPC upon a variety of available data sources.

Abstract: A method for determining a threshold write-in power of a compact disc (CD) includes the following steps: (a) recording M test data into M sectors of an outer area of the CD with a pickup by emitting laser beams of a variety of distinct test powers, (b) reading the test data with the pickup and calculating corresponding error rates of the test data, and (c) comparing the M test powers and calculating the threshold write-in power, which is between an upper-bound test power and a lower-bound test power.