KR0146122B1 - Optical disc recording and methdo & apparatus for confirming status of recording - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc recording and recording state checking apparatus and a method using the apparatus, wherein a diffraction grating (13) is provided between a calibrator lens (12) and a beam splitter (14) in a pickup structure of a conventional optical disc. By providing the installed device to output three laser beams, the portion with the highest output intensity is used for recording the optical disk, and the remaining portion is detected so as to detect the RF waveform of the disk track. The remaining beams are positioned on both tracks of the beam having the highest intensity to confirm the recording state, or the remaining beams are positioned on the same track as the beam having the highest intensity to confirm the recording state. In this way, since the optical disk apparatus according to the present invention records and confirms simultaneously, the recording speed is remarkably improved and the performance of the apparatus is greatly improved.

Description

Optical disc recording and recording status checking device and method

1 is a schematic configuration diagram of an optical disk apparatus according to the prior art.

2 is a state diagram in which a laser beam spot is formed on a disk by an optical disk apparatus according to the prior art.

3 shows a typical optical disk,

(a) is the structure diagram of the whole disc.

(b) is a figure of a concentric track.

(c) is a shape of a spiral track.

4 is a schematic configuration diagram of an optical disk device according to the present invention.

(A) and (b) of FIG. 5 is a state diagram in which a laser beam spot is formed on the disc by the optical disc apparatus according to the present invention, and a graph of light intensity of diffracted light according to the state.

Figure 6 shows the light intensity of the laser according to the present invention,

(a) is a light intensity graph of the magneto-optical disk.

(b) is the light intensity graph of the phase change disk.

7 and 8 are state diagrams in which a laser beam spot is formed on a disk according to another embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

11 laser diode 12 Calibrator lens

13 diffraction grating 14 beam splitter

15: 1/4 λ wavelength plate 16: objective lens

17: disc 18: cylindrical lens

19, 20: photodiode

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recordable optical disc, and more particularly, to an optical disc recording and recording state checking apparatus and a method using the apparatus for improving recording speed by simultaneously recording and confirming data.

Background Art [0002] In the conventional optical disc apparatus, a one beam method is used in which a pick-up is mainly concentrated in one spot of a laser beam. An example of this type of pickup structure is shown in FIG. 1, which will be described schematically.

The pickup structure of the optical disk apparatus according to the prior art includes a laser diode (1) to which light is radiated, a calibrator lens (2), a beam splitter (3), a 1/4 lambda wavelength plate (4), And an objective lens 5, a disc 6, a cylindrical lens 7, and a photodiode 8.

In the pickup structure configured as described above, when light is emitted from the laser diode 1, the emitted light becomes parallel light in the calibrator lens 2 to pass only the light of the required polarity in the beam splitter 3, and again. In the 1/4 lambda wavelength plate 4, the linear polarization is changed from linear polarization to the disk 6 through the objective lens 5. The light incident on the disk 6 is reversed in the rotational direction and is reflected back to the objective lens 5, and is again linearly polarized by the 1/4 lambda wavelength plate 4 to be used as the cylindrical lens 7 by the beam splitter 3. Reflected by the light, the light passing through the cylindrical lens 7 is incident on the photodiode 8. Light incident on the photodiode 8 is converted into an electrical signal, extracted into an RF signal, a focus error signal, a tracking error signal, and the like, and used as a signal for data and control.

According to the pick-up structure as described above, as shown in FIG. 2, by using one beam on the disc, information necessary for data and control during reproduction and recording is obtained.

In the figure, reference numeral 11 denotes one beam spot, 12 denotes a groove of a disc, and 13 denotes a land.

In other words, by setting the laser output lower than the recording time, the data and control information are obtained using only the reflected signal without affecting the surface of the disk. The magneto-optical disk method which modulates the magnetic field of the disk using a laser and a magnetic head, and the phase change type disk method which records using the medium which has the characteristic of a crystalline and amorphous according to temperature change are used.

Regardless of the type of the disc, the track structure is divided into two types, a concentric track (Fig. B) and a spiral track (Fig. C), as shown in FIG. The writing method differs from that in (a) in the drawing, 14 is the innermost circumference of the disk, 15 is the track, and 16 is the outermost circumference.

First, in the concentric track structure at the time of playback, the laser spot of pickup starts from point a and returns to point a, so if the track is rotated once and returned to point a, a track jump to point b is necessary. do. On the other hand, in the helical structure, even if starting from point c, the track jump does not need to be performed because it arrives at point d without returning to point c again.

In addition, in the concentric structure at the time of recording, the track jump does not jump to point b immediately after recording starting from point a but instead rotates once more to confirm the recorded data, and then track jumps to point b. In the helical structure, after starting at point c, when it reaches point d, the track jumps to point c again to check the recorded data, rotates once, and then starts recording at point d again.

In this way, in general, when the track structure is recorded in the concentric or spiral structure, the track jump must be performed once to confirm the recorded data.

Therefore, in order to record one track, one rotation is required for recording and one rotation is required to confirm the recorded data. Therefore, both tracks must be rotated.

As described above, since the time required for reproducing is twice as large as that of recording, it is an obstacle to improving the recording speed.

Accordingly, an object of the present invention for solving the above problems is to provide an optical disk apparatus capable of executing the checking operation of recorded data simultaneously with recording.

In order to achieve the object of the present invention, a laser diode that emits light, a calibrator lens for making the light emitted from the laser diode into parallel light, and a diffraction grating diffracts the light passing through the calibrator lens A beam splitter that transmits the diffracted light only with light of the required polarity, a 1/4 lambda wavelength plate that circularly polarizes the light transmitted by the beam splitter, an objective lens through which the polarized light passes, and light passing through the objective lens An incident disk and a cylindrical lens installed at right angles to the beam splitter so that the light incident on the disk is changed to circular polarized light having an opposite rotational direction, and is reflected by the beam splitter again through the objective lens and the 1/4? Wavelength plate; The optical disk recording and recording state checking apparatus comprising a photodiode to which light reflected from the cylindrical lens is incident It is a ball.

In addition, the recording and recording of the optical disc, characterized in that to output the three laser beams to use the portion with the highest output intensity for recording the optical disc, and to detect the RF waveform of the disc track with the remaining portion to confirm the recording state A method of checking the recording status is also provided.

Hereinafter, the present invention as described above will be described in more detail with reference to the accompanying drawings.

4 is a schematic configuration diagram of an optical disk apparatus according to the present invention, and (a) and (b) of FIG. 5 is a state diagram in which a laser beam spot is formed on the disk by the optical disk apparatus according to the present invention, and the state thereof. As a light intensity graph of diffracted light according to the present invention, the present invention is characterized in that the diffraction grating 13 is provided between the calibrator lens 12 and the beam splitter 14.

That is, the laser diode 11 for emitting light, the calibrator lens 12 for making the light emitted from the laser diode 11 into parallel light, and the light passing through the calibrator lens 12 are diffracted. A diffraction grating 13 for transmitting the light, a beam splitter 14 for transmitting only the light having a polarity necessary for diffracted light, a 1/4 lambda wavelength plate 15 for circularly polarizing the light transmitted from the beam splitter 14, and The objective lens 16 through which the light passes, the disk 17 through which the light passing through the objective lens 16 is incident, and the light incident on the disk 16 at right angles with the beam splitter 14 are installed. The cylindrical lens 18, which is reversed by the beam splitter 14 through the objective lens 16, the 1/4 lambda wavelength plate 15, is changed to the circularly polarized light having the opposite direction of rotation, and the cylindrical lens 18 It is composed of photodiodes 19 and 20 to which the reflected light is incident.

In the method of confirming the recording state by the optical disk apparatus according to the present invention configured as described above, three beams are generated by installing a diffraction grating and diffracting and dividing the light emitted from the laser diode. The side beams are arranged on both tracks of the main beam to read the pit information recorded on the tracks.

In other words, the RF signal and the control signal are obtained using the main beam during reproduction, the laser power and the control signal necessary for the recording are obtained using the main beam during recording, and the RF signal is obtained using the side beam. It becomes possible.

Referring to the operation of the apparatus of the present invention, the light emitted from the laser diode 11 passes through the calibrator lens 12 to become parallel light, and is diffracted by the diffraction grating 13 to the beam splitter 14. Only the light of the required polarity is transmitted, and is circularly polarized by the 1/4 lambda wavelength plate 15 and is incident on the disk 17 through the objective lens 16, and the incident light is converted into circularly polarized light whose rotation direction is opposite to the objective. It passes through the lens 16, is linearly polarized by the 1/4 lambda wavelength plate 15, is reflected by the beam splitter 14 to the cylindrical lens 18, and is incident on the photodiodes 19 and 20. . Light incident on the photodiodes 19 and 20 is converted into an electrical signal and used as a signal for data and control. At this time, the light is 0, ± 1, ± 2 ... in the process of diffraction by the diffraction grating Diffracted light is generated, but when three beams are used, only 0th order and ± 1th order are left.

Since the ± 1st order diffracted light (A) (B) has a relatively small light intensity compared to the main beam (C), when the main beam (C) has a recording power, the side beam (A) (B) is reproduced. You just need to have a dragon powder. At this time, since the RF signal read by the side beam (A) spot at the time of recording is information recorded by the main beam which is the side track, analyzing the signal of A can confirm whether the information recorded by the main beam is correctly recorded. have.

That is, the data can be confirmed by using the side beams A and B at the same time as recording the main beam. Therefore, if two or more tracks of information are recorded, the recording time can be shortened. As the amount of data increases, the effect increases.

6 shows laser light intensities in recording and reproducing, (a) is light intensity in reproducing, erasing and recording of magneto-optical discs, and (b) is light in reproducing, erasing and recording of phase change type discs. As the intensity, since the light intensity of the erase and the recording during the recording is the same in (a), the laser maintains a constant light intensity and the level of the RF signal read by the side beam is also constant.

However, in (b), since the erase and recording light intensities are different at the time of recording, an error may occur because the level of the RF signal read from the side beam is larger than when erasing. Therefore, in order to prevent this problem, the gain of the RF amp when recording is set lower than the gain of the RF amp when erasing.

FIG. 7 and FIG. 8 show another embodiment in which the spot formation state of the three beams is changed. In the case of FIG. 7, the three beams are arranged in the track direction. In structure and phase change discs, the cooling rate of the medium of the disc must be solved first. This method can immediately confirm the recording and can eliminate the difference of one track as in the above embodiment.

The form shown in FIG. 8 is a case where a multi beam is used, and in this structure, ± 1st-order diffraction light can be used as a tracking error signal, and ± 2nd-order diffraction light can be used as a data confirmation signal. Reference numeral 21 denotes a zero-order diffracted light as a main beam of a multi-beam, 22 denotes ± 1st-order diffracted light by a primary side beam, and 23 denotes ± 2nd-order diffracted light by a secondary side beam.

As described above, the optical disk apparatus according to the present invention has the effect of significantly improving the recording speed and significantly improving the performance of the device because recording and confirmation are performed simultaneously.

Claims (4)

A laser diode that emits light, a calibrator lens that makes the light emitted by the laser diode into parallel light, a diffraction grating that diffracts the light passing through the calibrator lens, and transmits only the polarized light through the diffracted light A beam splitter to be used, a 1/4 lambda wavelength plate for circularly polarizing the light transmitted from the beam splitter, an objective lens through which the polarized light passes, a disk on which light passing through the objective lens is incident, and a right angle to the beam splitter The light incident on the disk is changed to circularly polarized light with opposite rotational direction, and the objective lens, the cylindrical lens reflected by the beam splitter through the 1 / 4λ wavelength plate, and the light reflected from the cylindrical lens are incident. An optical disk recording and recording status checking apparatus comprising a photodiode. An optical disk recording and recording status checking method, characterized by outputting three laser beams, using the highest portion for recording the optical disk, and detecting the RF waveform of the disk track with the remaining portion. 3. The recording and recording state checking method of an optical disc according to claim 2, wherein the remaining beams are positioned on both tracks of the beam having the highest output intensity to confirm the recording state. The method of claim 2, wherein the remaining beams are positioned on the same track as the beam having the highest output intensity to confirm a recording state.