JPH05250675A - Optical recording and reproducing device - Google Patents

Abstract

PURPOSE:To simplify a verification operation and necessary circuit systems by judging the execution of a recording operation again in accordance with the detected output of a means of detecting the coincidence and noncoincidence of reproduced data and recorded data in a bit unit. CONSTITUTION:The coincidence/noncoincidence of the recorded data and reproduced data are detected by the output of an EX-OR gate 16 to which the recorded data and reproduced data are inputted by each one bit while the coincidence in time is made by a delay circuit 15. On which error correction line the data judged to be the noncoincidence exists is investigated in an ECC processing section 13 when the 'H' output in the case of the noncoincidence is supplied to a rewrite judgment section 17. In addition, this data is counted as a number of the noncoincidence data and whether the recording operation for the prescribed recorded data is ought to be executed again or not is judged in accordance with the number of the noncoincidence data. The need for storing, for example, the recorded data and the reproduced data respectively in a RAM, etc., for one sector is eliminated and, therefore, the hardware constitution is simplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording / reproducing apparatus,
In particular, the present invention relates to a verify operation for determining the quality of the recording state at the time of recording.

[0002]

2. Description of the Related Art Various optical recording / reproducing devices capable of recording various data on an optical disk by irradiating a spiral or concentric circular track with a laser beam and reading the recorded data have been put into practical use, and in particular recording. A magneto-optical disk (MO disk) system that is rewritable using a magnetic head that magnetically modulates data is considered to be useful.

[0003] Figure 4 example, those recording tracks showed an example of a format of a magneto-optical disk when an area for arranging the data is formed by a sample servo pits are discretely arranged, S ₁ ~ S ₄₂ indicates, for example, a sector that is divided into 42 in the circumferential direction. This magneto-optical disk records / reproduces data while being rotationally driven at CAV (constant angular velocity).

A track in each sector unit is shown in FIG.
The address test area AD is composed of a header segment H ₁ having an area where address data is recorded and an ALPC area (Automatic Laser Power Control Area), and a header segment H ₂ used for a trial writing area, etc. A data recording area DB, which is provided and subsequently records, for example, 20 bytes of data, is divided into ₃₀ segments SG _{1 to} SG ₃₀ .

FIG. 5B shows header segments H ₁ and H ₁ .
₂ and the data segments SG ₁ to SG ₃₀ and further expanded the first servo byte SB is disposed on the subsequently address or a magneto-optical (MO) data area to be recorded which are provided.

At least one pair of wobbling pits P ₁ and P ₂ which are deviated from the center of the track T to the outer peripheral side and the inner peripheral side are arranged on the servo bite SB and on the center line of the track T. The clock pit P ₃ is previously formed by embossing or the like.

A mirror surface M is formed in the middle of the wobbling pits P ₁ and P ₂ and the clock pit P ₃ , and the focus servo signal is detected by the laser light reflected from the mirror surface M and the laser power control is performed. -Le can also be done. Furthermore, the pits P ₄ and P whose access code as track information forms a gray code
Recorded by ₅ .

In such a magneto-optical disk, a tracking error signal is usually formed by calculating reflected light when the wobbling pits P ₁ and P ₂ are detected at the sample points t ₁ and t ₂ , and the clock pit P is formed. _The clock signal is formed by the signal detecting ₃ at sample point t ₃ .

In this magneto-optical disk, when the recording surface of the magneto-optical disk is irradiated with the laser beam along the track and a magnetic field is applied from the other surface of the magneto-optical disk by the magnetic head, the recording surface is at the Curie point or higher. Then, the data is recorded by being magnetized in the direction of the applied magnetic field. Further, when reading information from a magneto-optical disk on which data is recorded, recorded data is read by detecting reflected light of a laser beam by utilizing a magnetic cover effect. Then, the read reproduction signal is
After the waveform is shaped, it is binarized and the recorded data is read.

[0010]

By the way, when data is recorded on such a recordable optical disk, the data immediately after recording is reproduced at the same time as the recording operation, and this is reproduced by the recording head (in the case of MO system). The verify operation is performed by comparing the binary recording data supplied to the magnetic head) with the binary recording data. For example, the recorded data is 51 per sector
2 bytes are recorded. (However, ECC data,
(For example, 600 bytes of MO is recorded per sector including CRCC data and control data.)

In this case, the recording data of 512 bytes is supplied to the magnetic (magnetic field modulation) head and is temporarily stored in the RAM, for example. Immediately after recording, a laser spot (for laser scanning) different from the laser spot used for the recording operation (that is, the main spot continuously irradiated on the magnetic field application surface from the side facing the magnetic head) is used. The reflected light is obtained by using the side spots obtained by being divided by the diffraction grating in the optical system.
Reproduction processing of recorded data is performed.

As for this reproduction data, for example, 512 bytes corresponding to one sector are temporarily stored in the RAM. Then, the recorded data and the reproduced data stored in the RAM in sector units are compared with each other to determine whether they match or not, and if they do not match, it is determined that the rewriting (recording redo) operation of the data should be performed. However, there is a problem that an additional RAM or the like is required for the verify operation in units of sectors and the hardware configuration cannot be simplified.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and irradiates a main spot and a side spot on a recording track line and utilizes the main spot when recording data. The recording operation is performed by using the side spot, and further the recording operation is performed immediately after the data recorded by using the side spot, and the reproduced data and the recording data corresponding to each data are provided. Are sequentially supplied in 1-bit units, and whether or not the recording operation is performed again for predetermined recording data based on the coincidence detecting means for detecting coincidence / non-coincidence in 1-bit units and the coincidence / non-coincidence detection output by the coincidence detecting means The optical recording / reproducing apparatus is configured to have a rewrite determining means for determining.

Further, the rewrite determining means, when the amount of mismatch information set based on the error correction capability of the optical recording / reproducing apparatus is supplied from the match detecting means, performs a recording operation (rewrite) for the corresponding predetermined recording data. )
Try to determine to execute.

[0015]

By comparing the recording signal and the reproduction signal for verifying the same on a bit-by-bit basis, it becomes unnecessary to provide a storage means for holding the recording signal and the reproduction signal for verifying it on a sector basis, for example. Further, the coincidence detecting means for detecting coincidence / non-coincidence can be realized by a gate circuit having a simple structure. In such a case, the rewrite determination can be performed by detecting the number of supplied mismatch detection signals or the position within the sector in a certain data unit (for example, sector unit).

[0016]

1 is a block diagram showing an essential part of an optical recording / reproducing apparatus of the present invention, and 1 is a magneto-optical disk having a track format as described with reference to FIGS. The magneto-optical disk 1 is rotated by a spindle motor 2 at a constant angular velocity (CAV), for example.

Below the magneto-optical disk 1, an optical head 3 for irradiating a laser beam during recording or reproduction is arranged.
As is well known, the optical head 3 is composed of an optical system including a laser emission source, a diffraction grating, a collimator lens, a beam splitter, a biaxial device for controlling an objective lens, and a magneto-optical disk. It is equipped with a polarization beam splitter and a detector for detecting the reflected light of the.

In particular, the laser light is divided into 0th-order light, 1st-order light and -1st-order light by a diffraction grating to be three spots,
Moreover, as shown in FIG. 2, the respective spots (main spot 30 and side spots 31, 32) are irradiated so as to be aligned in the front-rear direction on the track T of the magneto-optical disk 1 (in-line method).

During reproduction, the light reflected by the main spot 30 is detected by the photodetector, and the recorded MO information and ROM information such as addresses and servos are obtained. Further, during recording, the main spot 30 is used to set the recording surface above the Curie point, and data is recorded by a magnetic field applied by the magnetic head 20 described later from the opposite side of the disk surface. Also,
The optical head 3 is also provided with a photodetector that detects reflected light corresponding to the side spot 31, and during the recording operation, the side spot 31 located on the rear side of the main spot 30 in the track direction causes the main spot 30 and Reflected light of the recorded data is obtained using the magnetic head 20, and a reproduction signal is obtained.

The output of each photodetector in the optical head 3 is supplied to the arithmetic circuit section 4 and various reproduction information is generated. For example, when two photodetectors for detecting the P-polarized component and the S-polarized component of the reflected light are provided, the arithmetic circuit unit 4 calculates the difference between the two photodetectors and MO
A data reproduction signal S _MO is obtained.

If, for example, one or both of the photodetectors in the optical head 3 is a light receiving element having a split surface, various servo signals S _SV are formed by extracting the push-pull signal. , The servo circuit 6 is supplied to drive the biaxial device, and tracking servo and focus servo are executed.

Further, the reproduction signal S _ROM of ROM data such as address information is obtained by summing the outputs from the respective division surfaces of the photodetector. The reproduction signal S _ROM of the ROM data is supplied to the control data reproducing unit 7 via the ROM data decoding unit 5, the address information, the master clock information and the like are extracted and input to the system controller 8. Reference numeral 9 denotes an address management unit, which exchanges address information at the time of recording / reproducing with the system controller 8.

Reference numeral 10 denotes an MO data decoding unit for decoding the MO signal S _MO extracted from the arithmetic circuit unit 4,
Reference numeral 11 is a binarization processing unit that performs binarization processing of the supplied signal, 12 is a data reproduction processing unit that extracts data and reproduces a read clock by a difference detection method, and 13 performs error detection and error correction. ECC processing unit, E
The output after the CC processing is supplied from the terminal 14 to a predetermined circuit section.

In the ECC processing unit 13, as shown in FIG. 3, for example, interleaving is performed with an interleaving factor = m, and for example, reproduction information (D _{11 to} D in units of one sector is used.
_nm ) Arranged for error correction. Then, as shown in the figure, the error correction processing is executed within the correction capability range for each of the _m error correction lines EL _{1 to} EL _m .

Reference numeral 15 is a delay circuit, 16 is an EX-OR gate, 17 is a rewrite judging section for judging whether or not the recording operation is properly performed by the verify operation at the time of recording, and indicates recording OK or recording NG. The determination signal S _V can be output to the system controller 8.
Reference numeral 18 denotes a delay amount control unit that controls the delay time in the delay circuit 15.

On the other hand, for the magneto-optical disk 1, a magnetic head portion 20 is provided at a position facing the optical head 3.
A magnetic field that is inverted by the recorded data is applied. That is, the recording data supplied from the terminal 21 is subjected to predetermined code modulation and block formation in the recording data processing unit 22, further error correction code and the like are added, and the recording data is supplied to the magnetic head 20. ..

The verify operation executed in such an optical recording / reproducing apparatus will be described below. At the time of recording, along with the recording operation by the main spot 30 and the magnetic head 20, the reflected light by the side spot 31 is detected, and the reproduced data thereof is binarized and sequentially supplied to the EX-OR gate 16 bit by bit.

On the other hand, the recording data output from the recording data processing unit 22 and being supplied to the magnetic head 20 is delayed by one bit as it is in the delay circuit 15 for a predetermined time and then supplied to the EX-OR gate 16. here,
A certain bit data in the recorded data and an output obtained by verify-reproducing the bit data are simultaneously EX-ORed.
The delay time in the delay circuit 15 is controlled by the delay amount control unit 18 so as to be input to the gate 16.

Of course, the recorded data and the reproduced data of the recorded data must match, but the delay circuit 15 makes a temporal match so that the recorded data and the reproduced data are input bit by bit. The match / mismatch can be detected by the output of the OR gate 16. When the “H” output in the case of non-coincidence is supplied to the rewrite judgment unit 17, the rewrite judgment unit 17 places the non-coincidence data on which error correction line (EL _{1 to} EL _m ) in the ECC processing unit 13. Whether it is located or not is checked, and the number of mismatched data on the error correction line is counted.

In this manner, for example, bit data in a unit of one sector is successively detected by the EX-OR gate 16 as a match / mismatch, and the rewrite determination section 17 further detects the data position (error correction line) and the number of mismatched data. Then, the rewrite determination unit 17 determines whether or not rewrite should be executed for each error correction line, depending on whether or not the number of mismatched data exceeds the error correction capability.

[0031] For example, when the error correction capability in the ECC processing unit 13 is to the K per each error correction line EL ₁ ~EL _m, each error correction line EL ₁ ~EL _m per counted discrepancy data number j (j ₁ ~j _m ) Is compared with this, and if there is even one error correction line with K <j, it is judged that rewriting should be executed because this sector cannot be accurately reproduced, and the judgment result (record A determination signal S _V indicating OK or recording NG) is output to the system controller 8. Based on this judgment signal S _V , the system controller 8 is required to continue the recording operation as it is if the recording is OK, or to temporarily suspend the recording operation if the recording is NG and perform the rewrite operation for the corresponding sector. Control each part.

In the present embodiment which executes such a verify operation, the match / mismatch between the recorded data and the reproduced data thereof is sequentially executed in 1-bit units. It is not necessary to store the data for each sector, and the coincidence detection operation is performed by EX-
It can be executed only by the OR gate 16. Therefore, the circuit configuration can be greatly simplified.

If the number of unmatched data j is less than the error correction capability K, it is not always necessary to execute rewriting, but the accuracy of the recording / reproducing operation may be strictly required (for example, The optical recording / reproducing apparatus for data storage) sets the number of unmatched data to be rewritten with a certain margin with respect to the error correction capability K, and performs the rewrite operation even if the number of unmatched data j is within the error correction capability K. It is preferable to execute it. In either case, it is possible to eliminate unnecessary rewrite operation to some extent and speed up the recording operation by determining execution / non-execution of rewrite based on the error correction capability. However, depending on the case, it may be possible to execute the rewrite operation when even one mismatch data exists.

By the way, since the interval L (see FIG. 2) between the main spot 30 and the side spot 31 is always constant, when the magneto-optical disk is driven by the CAV method as in this embodiment, the recording point is the disk outer periphery. As it goes to the side, the verify reproduction signal obtained by the side spot 31 in the verify operation is obtained closer to the timing when the recording signal is supplied to the magnetic head 20. Therefore, if the delay time in the delay circuit 15 is always constant, the recording signal and the verify reproduction signal corresponding thereto cannot be input to the EX-OR gate 16 at the same timing.

Therefore, the delay amount control section 18 inputs address information (for example, track address information) from the address management section 9, and determines at which position in the radial direction of the magneto-optical disk 1 the current recording operation is being executed. Based on this, the delay time is set and the delay time in the delay circuit 15 is controlled (the delay time is shortened toward the outer circumference side). This control realizes accurate match / mismatch detection on a bit-by-bit basis.

The main part of the optical recording / reproducing apparatus of the present invention is not limited to the configuration shown in FIG. Although the MO disk has been described, for example, WO (Write Onc
e) The present invention can be widely adopted as an optical recording / reproducing apparatus for a recordable medium such as a disc.

[0037]

As described above, in the optical recording / reproducing apparatus of the present invention, the coincidence detecting means compares the record data and the verify reproduction data in 1-bit units to judge the coincidence / non-coincidence. Since the position and the number of non-coincidence data on the interleave are counted from the output of the coincidence detection means to judge the execution of the rewrite, there is an effect that the circuit system required for the verify operation can be greatly simplified. In addition, since the rewrite determination means determines whether or not the rewrite is performed and the error correction capability of the optical recording / reproducing apparatus, unnecessary rewrite operation is omitted to some extent and the recording process can be speeded up. There is also an advantage.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of an in-line method of laser spot irradiation.

FIG. 3 is an explanatory diagram of ECC processing.

FIG. 4 is an explanatory diagram of a format of a magneto-optical disk.

FIG. 5 is an explanatory diagram of recording tracks.

[Explanation of symbols]

 1 Magneto-optical disk 2 Spindle motor 3 Optical head 8 System control unit 9 Address management unit 10 MO data decoding unit 11 Binarization processing unit 13 ECC processing unit 15 Delay circuit 16 EX-OR gate 17 Rewrite determination unit 18 Delay amount control unit 20 magnetic head 22 recording data processing unit 31 main spot 31.32 side spot

Claims (2)

[Claims] 1. A main spot and a side spot are irradiated onto a recording track line, and when recording data, a recording operation is performed using the main spot, and immediately after the data recorded using the side spot is recorded. A recording / reproducing processing unit capable of performing a reproducing operation is provided, and reproduced data and record data corresponding to each data are sequentially supplied in 1-bit units. An optical recording device comprising: a detection unit; and a rewrite determination unit that determines whether or not to perform a recording operation again for predetermined recording data based on the detection output by the coincidence detection unit. Playback device. 2. The rewrite determination means, when the amount of mismatch information set based on the error correction capability of the optical recording / reproducing apparatus is supplied from the match detection means, executes the recording operation again for predetermined recording data. The optical recording / reproducing apparatus according to claim 1, wherein the optical recording / reproducing apparatus is determined.