초록 ▼

A focus jump technique enables focus control on recording layers of a disc in such a manner that its effect is not absorbed by disturbance or a variation in the movement speed of an objective lens. The technique involves monitoring level of a focus error signal and rejecting noise from the error sig

A focus jump technique enables focus control on recording layers of a disc in such a manner that its effect is not absorbed by disturbance or a variation in the movement speed of an objective lens. The technique involves monitoring level of a focus error signal and rejecting noise from the error signal. A speed sensor detects movement speed of an objective lens; and a speed control circuit generates a voltage for controlling the objective lens, based on the detected movement speed. Movement speed of the objective lens is detected during focus jump, a corresponding lens drive signal is generated, and an end position is determined from behavior of the error signal immediately before the end of the jump. A focus control is pulled, from a focus point corresponding to one recording layer, into a focus point corresponding to another recording layer forcibly in a stable manner.

대표청구항 ▼

What is claimed is: 1. An optical disc recording method for recording data in a first recording layer and/or a second recording layer by irradiating one surface of an optical disc with laser light, the method comprising the steps of, when it is judged that addresses at which continuous data is to b

What is claimed is: 1. An optical disc recording method for recording data in a first recording layer and/or a second recording layer by irradiating one surface of an optical disc with laser light, the method comprising the steps of, when it is judged that addresses at which continuous data is to be randomly recorded are positioned in both the first recording layer and the second recording layer: recording data in the first recording layer with the laser light set for recording power; stopping recording in the first recording layer; switching the laser light to nonrecording power and performing an interlayer jump from the first recording layer to the second recording layer; and when the performing an interlayer jump has not succeeded, performing servo recovery processing; when the performing an interlayer jump has succeeded, detecting a target position for data recording in the second recording layer, switching the laser light to recording power, and resuming a data recording operation. 2. An optical disc recording method for irradiating one surface of an optical disc with laser light and/or recording data in a first recording layer, which is near the surface, and in a second recording layer, which is far from the surface, the method comprising the steps of: when it is judged that addresses at which continuous data is to be recorded are positioned first in the first recording layer and then in the second recording layer, exercising first interlayer jump control to: record data in the first recording layer with the laser light set to recording power, stop recording in the first layer when the next data is to be recorded in the second recording layer, switch the laser light to nonrecording power, perform an interlayer jump from the first recording layer to the second recording layer, when the performing an interlayer jump has not succeeded, perform servo recovery processing, and when the performing an interlayer jump has succeeded, detect a target position for data recording in the second recording layer, switch the laser light to recording power, and resume a data recording operation; and when it is judged that addresses at which continuous data is to be recorded are positioned first in the second recording layer and then in the first recording layer, exercising second interlayer jump control to: record data in the second recording layer with the laser light set to recording power, stop recording in the second layer when the next data is to be recorded in the first recording layer, switch the laser light to nonrecording power, perform an interlayer jump from the second recording layer to the first recording layer, when the performing an interlayer jump has not succeeded perform servo recovery processing, and when the performing an interlayer jump has succeeded detect a target position for data recording in the first recording layer, switch the laser light to recording power, and resume a data recording operation. 3. The optical disc recording method according to claim 1 or 2, wherein the nonrecording power used for an interlayer jump is reproduction power. 4. An optical disc apparatus for recording data in a first recording layer and/or a second recording layer by irradiating one surface of an optical disc with laser light, the apparatus comprising: a laser for radiating laser light; a laser power control circuit for controlling the output of the laser; an objective lens for collecting laser light and directing the collected laser light to the recording layers of the optical disc; a focus error signal generation circuit for generating a focus error signal in accordance with light reflected from the objective lens; a focus control signal generation circuit for generating a focus control signal from the focus error signal to control the objective lens; a drive voltage generation circuit for generating a voltage necessary for moving the objective lens; movement means for moving the objective lens in a direction substantially perpendicular to the recording layers of the optical disc in accordance with an output that is generated by the drive voltage generation circuit; and a control circuit which, when it is judged that addresses at which continuous data is to be randomly recorded are positioned in both the first recording layer and the second recording layer, records data in the first recording layer with the laser light set to recording power, stops recording in the first layer, switches the laser light to nonrecording power, performs an interlayer jump from the first recording layer to the second recording layer, when the performing an interlayer jump has not succeeded performs servo recovery processing, and when the performing an interlayer jump has succeeded detects a target position for data recording in the second recording layer, switches the laser light to recording power, and resumes a data recording operation. 5. An optical disc apparatus for irradiating one surface of an optical disc with laser light and recording data in a first recording layer, which is near the surface, and in a second recording layer, which is far from the surface, the optical disc apparatus comprising: a laser for radiating laser light; a laser power control circuit for controlling the output of the laser; an objective lens for collecting laser light and directing the collected laser light to the recording layers of the optical disc; a focus error signal generation circuit for generating a focus error signal in accordance with light reflected from the objective lens; a focus control signal generation circuit for generating a focus control signal from the focus error signal to control the objective lens; a drive voltage generation circuit for generating a voltage necessary for moving the objective lens; movement means for moving the objective lens in a direction substantially perpendicular to the recording layers of the optical disc in accordance with an output that is generated by the drive voltage generation circuit; and a control circuit which, when it is judged that addresses at which continuous data is to be recorded are positioned first in the first recording layer and then in the second recording layer, exercises first interlayer jump control to: record data in the first recording layer with the laser light set to recording power, stop recording in the first layer, switch the laser light to nonrecording power, perform an interlayer jump from the first recording layer to the second recording layer, when the performing an interlayer jump has not succeeded perform servo recovery processing, and when the performing an interlayer jump has succeeded detect a target position for data recording in the second recording layer, switch the laser light to recording power, and resume a data recording operation; and when it is judged that addresses at which continuous data is to be recorded are positioned first in the second recording layer and then in the first recording layer, exercises second interlayer jump control to: record data in the second recording layer with the laser light set to recording power, stop recording in the second layer, switch the laser light to nonrecording power, perform an interlayer jump from the second recording layer to the first recording layer, when the performing an interlayer jump has not succeeded perform servo recovery processing, and when the performing an interlayer jump has succeeded detect a target position for data recording in the first recording layer, switch the laser light to recording power, and resume a data recording operation. 6. The optical disc apparatus according to claim 4 or 5, wherein the nonrecording power used for an interlayer jump is reproduction power.