JP2000339683A - Optical recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress frequent writing operations on an SDL caused by the noise of tracking signals while a user is using the device. SOLUTION: An optical recording and reproducing device is provided with an optical pickup 4, which irradiates light beams along a spiral track formed on a magneto-optical disk 1 and detects reflected light beams, and a control circuit 7 which conducts a tracking by the reflected light beams. The circuit 7 detects tracking and track jump signals during a certifying of the disk 1 and executes a control so that address data of the sector of the portion, where tracking signal strength becomes more than 7% of the track jump signal strength, are written into a defect control region.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for comparing a track jump signal and a tracking error signal at the time of certifying (physical format) when initializing a disk-shaped optical recording medium, thereby enabling the user to use the optical recording medium. A so-called SDL (Secondary Defect List: 2) that records address data of a defective sector in a defect management area when used.
The present invention relates to an optical recording / reproducing apparatus that suppresses replacement processing.

[0002]

2. Description of the Related Art FIG. 1 is a block circuit diagram of a conventional optical recording / reproducing apparatus D. In FIG. 1, reference numeral 1 denotes a magneto-optical disk, which is a kind of disk-shaped optical recording medium, 2 denotes a motor for rotating the magneto-optical disk during recording and reproduction, and 3 denotes an up and down direction perpendicular to the magneto-optical disk surface during recording. A magnetic head 4 for applying a magnetic field modulated in a direction irradiates the recording bits with light during reproduction and an optical pickup for detecting a digital signal from the Kerr rotation angle of the reflected light. Reference numeral 5 denotes a recording data circuit which modulates recording data to generate a magnetic recording signal and an optical recording signal and supplies them to the magnetic head 3 and the optical pickup 4, and 6 receives the reflected light from the magneto-optical disk surface by the optical pickup 4. And a reproduced data circuit for converting a signal based on the reflected light into digital reproduced data.

A control circuit 7 has a CPU (Cent
er of Processing Unit (Central Processing Unit), etc., and various controls are performed based on instructions from a computer 9 having a ROM or the like incorporating drive program software. The commands include a recording operation command, a reproduction operation command, a certification (Ce
rtify; physical format) command, verify (Verif)
y; verification) command. Reference numeral 8 denotes a storage circuit which divides the written data for each sector and supplies it to the recording data circuit 6 as recording data.

[0004] The certification operation is as follows. When the magneto-optical disk is initialized (physical format), appropriate data is written to the entire recording area of the magneto-optical disk, and the data in the header and data sections in the sector is read out, and the recording surface is scratched or adhered. For this reason, a defective sector that cannot be reproduced is detected, and the address data of the defective sector is transferred to a defect management area (DMA) provided on the inner and outer peripheral sides of the magneto-optical disk.
This is an operation of writing in a PDL (Primary Defect List: basic defect list area).

The verify operation is as follows. When the user writes data in the recording area of the magneto-optical disk, this operation verifies whether or not the data has been correctly written. After the data has been written, the data is read and a non-reproducible defective sector is detected. Next, the address data of the defective sector and the address data of another sector (alternate sector) for recording data to be written are written to the SDL.

The process of writing address data and the like of a defective sector into PDL and SDL as described above is generally called a replacement process.

Conventionally, such an optical recording / reproducing apparatus D is an optical disk apparatus in which various marks such as address marks indicating physical positions are recorded in a sector, and includes an operation instruction section and an operation instruction section. By providing a detection limit control unit that determines the detection limit of various marks and a mark detection circuit that detects various marks based on the determined detection limit, the detection limit can be determined according to the content of the operation. It has been proposed that a replacement process can be performed (conventional example 1: Japanese Patent Laid-Open No. 5-298832). For example, the detection limit of 80% is determined as “good” when 2.4 bytes (20 bits) or more out of 3 bytes (24 bits) match.

An optical disk apparatus for recording / reproducing data on / from an optical disk comprising a recording area comprising a plurality of sectors and an alternative area comprising a plurality of sectors, comprising: a detecting means for detecting an error in the reproduced data in byte units. And when the detecting means continuously detects an error of 2 bytes or more, the data recorded in the sector where the error has occurred is recorded in the sector of the alternative area, and the sector where the error occurs is a land. Processing means for recording data recorded in the sector of the adjacent groove also in the sector of the alternative area, and when the sector in which the error occurred is the groove, also recording data recorded in the sector of the adjacent land in the sector of the alternative area. Is known to suppress the increase in the number of sectors in which defects exist (see Conventional Example 2: See Japanese Unexamined Patent Publication No. 64062).

[0009]

However, in the above-mentioned conventional examples 1 and 2, basically, when a defective sector is detected, the presence or absence of an error is confirmed in byte length units. Even if a signal (hereinafter, referred to as a tracking signal) has noise enough to cause tracking to be lost, data in a sector may be read out normally. Therefore, the PDL replacement process may be performed even if there is noise due to scratches on the recording surface. A situation that did not occur occurred. In addition, when a real-time image is recorded by a monitoring camera or the like using an optical disk certified by such an optical disk device, the noise of the tracking signal becomes an error depending on various optical recording / reproducing devices, and the SDL
In some cases, replacement processing for writing data into the memory frequently occurs. As a result, the recording process is delayed, and it is impossible to continuously record the real-time image, and there is a problem that many frames are dropped in the image.

Therefore, the present invention has been completed in view of the above circumstances, and an object of the present invention is to perform a replacement process at a relatively low level of a tracking signal at the time of certification to reduce noise of the tracking signal at the time of user use. The purpose of the present invention is to prevent frequent writing operations to the SDL from occurring, and to prevent the occurrence of a large number of dropped frames when recording a real-time image.

[0011]

According to the present invention, there is provided an optical recording / reproducing apparatus which irradiates light along a spiral recording track formed on a disk-shaped optical recording medium and detects reflected light thereof, A control circuit for performing tracking by the reflected light, wherein the control circuit detects a tracking error signal and a track jump signal when the optical recording medium is initialized, and the tracking error signal intensity becomes 7% or more of the track jump signal intensity. The address data of the changed sector is written in a defect management area of the optical recording medium.

According to the present invention, with the above-described configuration, it is possible to prevent a user from frequently performing a write operation on an SDL due to a noise of a tracking signal when recording on an optical recording medium. It is possible to prevent a delay in the recording process and a large number of dropped frames of the image.

In the present invention, preferably, the control circuit stores address data of a sector in which a tracking error signal intensity is 7% or more of a track jump signal intensity and an error of 5 bytes or more per sector is detected. In the defect management area.

With such a configuration, the tracking error signal strength is conventionally 15 to 2 times the track jump signal strength.
The certification at the level of about 0% is performed at a strict level of 7% or more, and the PDL replacement processing is performed when an error of 5 bytes or more per sector is detected, so that the certification is performed at a stricter level. That is, it is possible to further suppress the frequent occurrence of the SDL replacement process at the time of user use.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical recording apparatus according to the present invention will be described below. The optical recording apparatus of the present invention is the optical recording apparatus D of FIG.
And the basic configuration is the same, and a control circuit 7 different from the conventional one will be described. The control circuit 7 detects the tracking signal and the track jump signal at the time of initialization (certify) of the optical recording medium 1, and optically records the address data of the sector where the tracking signal intensity becomes 7% or more of the track jump signal intensity. Control is performed so that the data is written to the defect management area of the medium 1.

First, the method of detecting the tracking signal is shown in FIG. In FIG. 1, reference numeral 20 denotes a disk-shaped optical recording medium having a spiral recording track (hereinafter, referred to as a track) formed on a main surface thereof;
Are guide grooves (grooves) formed along the track;
2 is a land as a track on which recording bits are formed,
Reference numeral 23 denotes an objective lens, which is one component of the optical pickup;
Is a tracking signal detector which is one component of the optical pickup and is composed of two photodetectors such as photodiodes. Although the detailed configuration of the optical pickup is not particularly shown, its basic configuration is a light source section such as a semiconductor laser, a beam splitter that reflects light from the light source section toward the optical recording medium, and a light splitter that reflects light from the beam splitter. It comprises an objective lens for focusing light on a track of a recording medium, a tracking signal detector for detecting reflected light reflected by the track and reversely passing through a beam splitter, a focus detector, and the like.

The tracking signal detector 24
Operates as shown in FIG. FIG. 7A shows the reflected light intensity distribution when the focus of the light applied to the track matches the recording bit on the track, and FIG. 7B shows the focus of the light applied to the track on the track. 5 shows a reflected light intensity distribution when the position is shifted from a recording bit. As shown in (b), when a track shift occurs, the reflected light intensity distribution is biased. When the track shift is further increased, the reflected light intensity further biases. That is, noise of the tracking signal increases.

Next, the track jump signal will be described. FIG. 4 is a plan view of a disk-shaped optical recording medium M1 such as an optical disk, a magneto-optical disk, a phase change optical disk, and a DVD (Digital Versatile Disk). , 1
Reference numeral 2 denotes an outer management area, and reference numeral 13 denotes a spirally formed track. For example, when the track 13 is tracked from the inside during reproduction (arrow in the figure), if the optical pickup is stopped at a certain position, it is inevitably necessary to jump inward by one track (open in the figure). Arrow). At the time of this jump, a signal having a relatively large intensity is detected by the tracking signal detector 24, and the signal is called a track jump signal.

The track jump signal is, specifically, the level (intensity) of a noise signal when the track crosses a groove. As shown in FIG. 5, in the present invention, a tracking error occurs and the tracking signal intensity is reduced. When the jump signal becomes 7% or more, an operation of writing the sector of that portion to the defect management area is performed. Incidentally, the tracking signal strength during a normal tracking operation is at a level of 7% or less of the track jump signal. Conventionally, in general, in the certification, an operation of writing to the defect management area at a level of about 15% to 20% or more has been performed. As a result, the writing operation to the SDL frequently occurs, for example, when a real-time image is recorded, a recording process is delayed, and a large number of image frames are dropped, so that image recording cannot be continuously performed satisfactorily.

FIG. 6 shows a defect management area of the optical recording medium M1. In the figure, reference numerals 14a and 14b denote an inner defect management area and an outer defect management area for registering address data and the like of a defective sector, which are PDL and SDL.
including. The information on the defective sectors recorded in the PDL and SDL in the inner defect management area 14a and the outer defect management area 14b is read when the optical recording medium M1 is loaded in the optical recording / reproducing apparatus, and is read / written. Stored in the device. Then, at the time of normal recording and reproduction, processing based on the information is performed in the optical recording and reproducing apparatus.

In the present invention, the address data of a sector in which the tracking error signal strength is 7% or more of the track jump signal strength and an error of 5 bytes or more per sector is detected is preferably written in the defect management area. If the PDL replacement process is performed at less than the above, the number of replacement sectors is too large at the time of certification, and it becomes difficult to complete the certification normally, and the yield and mass productivity of usable optical recording media decrease.

In the present invention, the optical recording medium M1 is a medium in which optically reproducible information is recorded on a main surface of a disk-shaped substrate made of a transparent material such as polycarbonate or glass or an opaque material such as ceramics. And CD-R
(Compact Disc Recordable), CD-RW (Compact D
isc ReWitable), DVD-R (DVD Recordable),
DVD-RW (DVD ReWitable), DVD-RAM,
Optical disks such as phase-change optical disks and magneto-optical disks are included.

Thus, according to the present invention, when a user records on an optical recording medium, S
This has the effect of suppressing frequent write operations to the DL, for example, preventing a delay in the recording process when recording a real-time image and preventing a large number of dropped frames in the image.

It should be noted that the present invention is not limited to the above embodiment, and various changes may be made without departing from the scope of the present invention.

[0025]

Embodiments of the present invention will be described below.

(Embodiment) The optical recording / reproducing apparatus D of FIG. 1 was constructed as follows. As an optical recording medium, a magneto-optical disk having a diameter of 3.5 inches and a storage capacity of 640 MB (megabytes) was used, and TbFe, TbFeCO, GdFeCo, G
The recording surface was formed by forming a known rare earth-transition metal amorphous alloy layer such as dTbFeCo by a sputtering method. The control circuit 7 of the optical recording / reproducing apparatus D detects a tracking signal and a track jump signal at the time of certification of the initialization of the magneto-optical disk, and the tracking signal intensity is 7% or more of the track jump signal intensity and 5 bytes per sector. The operation of writing the address data of the sector in which the above error is detected into the defect management area of the magneto-optical disk is performed. The comparison between the tracking signal strength and the track jump signal strength can be performed by a comparison circuit composed of an operational amplifier and the like, and the error detection in the sector is performed by digitally comparing test data to be written for test and read data. It can be easily executed by providing a logic circuit or the like.

On the other hand, as a comparative example 1, replacement processing is performed when the tracking signal intensity is 7% or more of the track jump signal intensity and an error of 6 bytes or more per sector is detected at the time of certification of the magneto-optical disk. I did it.

As a comparative example 2, when the tracking signal intensity is 7% or more of the track jump signal intensity and the error of 7 bytes or more per sector is detected during the certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 3, when the tracking signal intensity is 8% or more of the track jump signal intensity and the error of 5 bytes or more per sector is detected at the time of certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 4, when the tracking signal intensity is 8% or more of the track jump signal intensity and the error of 6 bytes or more per sector is detected during the certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 5, when the tracking signal intensity is 8% or more of the track jump signal intensity and the error of 7 bytes or more per sector is detected at the time of certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 6, when the tracking signal intensity is 9% or more of the track jump signal intensity and the error of 5 bytes or more per sector is detected during the certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 7, when the tracking signal intensity is 9% or more of the track jump signal intensity and the error of 6 bytes or more per sector is detected during the certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 8, when the tracking signal intensity is 9% or more of the track jump signal intensity and the error of 7 bytes or more per sector is detected at the time of certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 9, when the tracking signal intensity is 10% or more of the track jump signal intensity and the error of 6 bytes or more per sector is detected at the time of certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 10, when the tracking signal intensity is 10% or more of the track jump signal intensity and an error of 6 bytes or more per sector is detected during the certification of the magneto-optical disk, the replacement process is performed.

As a comparative example 11, when the tracking signal intensity is 10% or more of the track jump signal intensity and the error of 7 bytes or more per sector is detected at the time of certification of the magneto-optical disk, the replacement process is performed.

When the magneto-optical disk certified by the optical recording / reproducing apparatus of the present embodiment and Comparative Examples 1 to 11 was used for a TV camera monitoring apparatus for recording an image in real time, the frame drop of the image is shown in Table 1. It was a result.

[0039]

[Table 1]

As shown in Table 1, in the cases other than the present embodiment, many frames were dropped in the image, and the recording process was delayed, so that satisfactory recording could not be performed.

[0041]

According to the present invention, a control circuit detects a tracking signal and a track jump signal at the time of initialization of an optical recording medium, and the address of a sector in a portion where the tracking signal intensity becomes 7% or more of the track jump signal intensity. By writing data to the defect management area of the optical recording medium, it is possible to suppress frequent writing operations to the SDL due to the noise of the tracking signal when the user records information on the optical recording medium. This has the effect of preventing a delay in the recording process when recording the image and preventing a large number of dropped frames from occurring in the image.

Also, preferably, the control circuit makes the tracking signal strength 7% of the track jump signal strength.
By writing the address data of the sector that has detected the error of 5 bytes or more per sector into the defect management area, the certification is performed at a stricter level, and the SDL replacement processing when the user is used is further reduced. Can be suppressed.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of an optical recording / reproducing apparatus D of the present invention.

FIG. 2 is a perspective view of an objective lens of an optical pickup and a tracking signal detector, for explaining a tracking signal detection mechanism.

FIG. 3A is a side view showing the intensity distribution of reflected light when the focus of light applied to the track coincides with the track, and FIG. 3B is a view in which the focus of light applied to the track is shifted from the track; FIG. 4 is a side view showing an intensity distribution of reflected light when the light is present.

FIG. 4 illustrates a track jump signal;
It is a top view of an optical recording medium.

FIG. 5 is a waveform diagram showing an example of a waveform of a track jump signal.

FIG. 6 is a plan view showing an optical recording medium according to the present invention and showing a defect management area.

[Explanation of symbols]

 1: Magneto-optical disk 3: Magnetic head 4: Optical pickup 5: Recording data circuit 6: Reproduction data circuit 7: Control circuit 8: Storage circuit 9: Computer

Claims (2)

[Claims] An optical pickup for irradiating light along a spiral recording track formed on a disk-shaped optical recording medium and detecting a reflected light thereof, and a control circuit for performing tracking by the reflected light. The control circuit detects a tracking error signal and a track jump signal at the time of initialization of the optical recording medium, and stores address data of a sector where the tracking error signal intensity is 7% or more of the track jump signal intensity on the optical recording medium. An optical recording / reproducing apparatus for writing in a defect management area. 2. The control circuit writes address data of a sector in which a tracking error signal intensity is 7% or more of a track jump signal intensity and an error of 5 bytes or more per sector is detected in a defect management area of an optical recording medium. The optical recording / reproducing apparatus according to claim 1, wherein: