JP3017738B2 - Optical disk drive - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial application field) The present invention relates to, for example, an optical disc apparatus that records or reproduces information on an optical disc.

2. Description of the Related Art As is well known, various disk devices have been developed which record information on an optical disk or read information recorded on an optical disk by using a laser beam output from a semiconductor laser, for example.

In such an optical disk device, before writing or reading information on a new optical disk, a block header A (format) including, for example, a block number, a track number, and a sector number as address information recorded at the time of manufacturing the optical disk. data)
Usually, a format check is performed to determine the quality of the data.

Such a format check is to read address information recorded in advance and the entire surface of the optical disk and check whether the address information is correctly recorded. This format check is normally performed only once for a new optical disk, and is recorded at a predetermined position inside or outside the user area so that address information that has not been correctly read can be handled as defect information.

However, when checking the format of a write-once optical disc, there are the following problems. For example, when a format check is performed on a recording medium such as a floppy disk or a magnetic disk which can be freely read and written, it is necessary to check the validity of the address information as well as the reproduction after writing the data in the data recording area. It is designed to check whether the data recording area can be normally written or reproduced.

However, in the case of a write-once optical disc, data cannot be recorded in the data recording area of the user. Therefore, at present, address information is read out by reproduction and only the validity is checked.

That is, since the data recording area has not been substantially checked, there is a disadvantage that recording or reproduction cannot be performed normally if the data recording area has a defect.

(Problems to be Solved by the Invention) As described above, in the present invention, for example, in the format check of a write-once optical disc, the data recording area is not substantially checked, so that the data recording area has a defect. This was done to eliminate the drawback that the address information of the optical disc including the write-once type and the data recording area could not be recorded or played back properly if there was a defect. It is another object of the present invention to provide an optical disk device that can reliably detect a defect in a data recording area and perform normal recording or reproduction.

[Structure of the Invention] (Means for Solving the Problems) An optical disc apparatus according to the present invention is an optical disc which is recorded in a block unit including a header area and a data recording area, wherein the header area and the data area are continuous. An optical disc apparatus for recording data on an optical disc arranged in a manner as described above, wherein a condensing means for irradiating a light beam weaker than a level at which data is recorded on the data recording area; and a light beam irradiated by the condensing means. Reading means for reading address information from a header area for each block, first detecting means for detecting a defect in the header area for each block from the address information read by the reading means, and detection by the first detecting means A focus error indicating a focus state of the light beam irradiated by the light condensing means on the optical disk so that A second detecting means for detecting a defect in the data recording area of each block by a signal, and a detection result of the defect detected by the second detecting means and the first detecting means. A storage unit for temporarily storing the block including the header region or the data recording region with the address information by the reading unit, and temporarily sequentially storing the block as defect information, and for all regions of the plurality of blocks on the optical disc, After the detection of the defect by the first and second detection means is completed,
Control means for controlling the recording of the defect information of all the blocks temporarily and sequentially stored in the storage means into a predetermined maintenance area on the optical disk.

Further, the optical disc device of the present invention is a write-once optical disc in which data is recorded in block units including a header area and a data recording area, wherein the header area and the data area are continuously arranged. In an optical disc device for recording data, a condensing means for irradiating a light beam weaker than a level at which data is recorded on the data recording area, and an address from the header area of each block irradiated with the light beam by the condensing means Reading means for reading information; first detecting means for detecting a defect in the header area of each block from the address information read by the reading means; and The focus error signal indicating the focus state of the light beam irradiated by the light condensing means on the write-once optical disc is used to control the light beam. Second detecting means for detecting a defect in a data recording area for each of the checksums, and a header which detects the defect detected by the second detecting means and the first detecting means. A storage unit for temporarily associating the block including an area or a data recording area with the address information by the reading unit and sequentially storing the block as defect information; and a storage unit for all areas of a plurality of blocks on the write-once optical disc. After the completion of the defect detection by the first and second detection means, the defect information of all the blocks temporarily stored in the storage means is sequentially stored in a predetermined maintenance area on the write-once optical disc. Control means for controlling recording.

(Operation) The present invention relates to an optical disc device that records data on an optical disc that is recorded in units of blocks including a header area and a data recording area, and in which the header area and the data area are arranged continuously. The data recording area is irradiated with a light beam weaker than the level at which data is recorded, address information is read from the header area of each block irradiated with the light beam, and the header of each block is read from the read address information. A defect in the data recording area of each block is detected by a focus error signal indicating a focus state of the irradiated light beam on the optical disc so that the defect is detected in the area, and the defect is detected. The detection result of the detected defect includes the header area or data recording area in which the defect was detected. The lock is temporarily stored sequentially as defect information in association with the address information, and for all areas of the plurality of blocks on the optical disc, after the detection of the defect is completed, the temporarily stored The defect information of all blocks is recorded in a predetermined maintenance area on the optical disk.

The present invention also relates to a write-once optical disc that is recorded in block units including a header area and a data recording area, and records data on the write-once optical disc in which the header area and the data area are continuously arranged. In the optical disk device, the data recording area is irradiated with a light beam weaker than the level at which data is recorded, and the address information is read from the header area of each block irradiated with the light beam. A defect in the header area of each block is detected, and the data recording area of each block is detected by a focus error signal indicating a focus state of the irradiated light beam on the write-once optical disc so as to continue the detection. Detect defects in
The detection result of the detected defect is temporarily stored as defect information in association with the address information and the block including the header area or the data recording area where the defect is detected, and temporarily stored on the write-once optical disc. After the detection of the defect is completed for the entire area of the block, the defect information of the temporarily stored all blocks is recorded in a predetermined maintenance area on the write-once optical disc. It was done.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a disk device. Grooves (recording tracks) are formed in a spiral shape on the surface of an optical disc (recording medium) 1. The optical disc 1 is rotated at a constant speed by a motor 2, for example. The motor 2 is controlled by a motor control circuit 18.

As shown in FIG. 2, the optical disc 1 has a doughnut-shaped metal film layer such as tellurium or bismuth, that is, a recording film, coated on the surface of a substrate formed in a circle of glass or plastics, for example.
A notch, that is, a reference position mark 40 is provided near the center of the metal coating layer.

As shown in FIG. 2, the optical disc 1 is divided into 256 sectors "0 to 255" with the reference mark 40 being "0". Variable length information is recorded over a plurality of blocks on the optical disc 1, and 300,000 blocks are formed on 36,000 tracks on the optical disc 1.

The number of sectors of one block on the optical disc 1 is, for example, 40 sectors on the inner side and 20 sectors on the outer side. At the start position of the block, a block header A as address information including a block number, a track number, a sector number, and the like is recorded, for example, when the optical disc 1 is manufactured.
Then, as shown in FIG. 3, following the block header A, a data recording area B in which data can be recorded.
Is provided.

When each block on the optical disc 1 does not end at the sector switching position, a block gap is provided so that each block always starts from the sector switching position.

Recording and reproduction of information on the optical disk 1 are performed by the optical head 3. The optical head 3 is fixed to a drive coil 13 constituting a movable portion of a linear motor, and the drive coil 13 is connected to a linear motor control circuit 17.

A linear motor position detector 26 is connected to the linear motor control circuit 17, and the linear motor position detector 26 detects the optical scale 25 provided on the optical head 3 to generate a current position signal. Output.

Further, a permanent magnet (not shown) is provided at a fixed portion of the linear motor, and the optical coil 3 is moved in the radial direction of the optical disc 1 by exciting the drive coil 13 by the linear motor control circuit 17. It has become so.

An objective lens 6 is held by the optical head 3 by a wire or a leaf spring (not shown). The objective lens 6 is moved in a focusing direction (an optical axis direction of the lens) by a drive coil 5, and is moved by a drive coil 4. It is arranged movably in the tracking direction (the direction orthogonal to the optical axis of the lens).

The laser light generated by the semiconductor laser 9 driven by the laser control circuit 14
a, the light is irradiated onto the optical disc 1 through the half prism 11b and the objective lens 6, and the reflected light from the optical disc 1 is
The light is guided to the half prism 11c via the objective lens 6 and the half prism 11b, and one of the light beams separated by the half prism 11c is guided to the pair of tracking position sensors 8 via the condenser lens 10.

The other light split by the half prism 11c is guided to a pair of focus position sensors 7 via a condenser lens 11d and a knife edge 12.

The output signal of the tracking position sensor 8 is supplied to a tracking control circuit 16 via a differential amplifier OP1. The tracking error signal output from the tracking control circuit 16 is supplied to the linear motor control circuit 17 and also to the drive coil 4 in the tracking direction, so that the laser light is tracked on a predetermined track on the optical disc 1. Is controlled as follows. Further, the tracking error signal is sent to the bus line 20 via the A / D converter 21.
Sent to the CPU 23 so that the data can be captured by the CPU 23.

The focus position sensor 7 outputs a signal relating to the focus point of the laser beam, and this signal is supplied to the focusing control circuit 15 via the differential amplifier OP2. The output signal of the focusing control circuit 15 is supplied to a focus error signal detection circuit 33,
The laser beam is supplied to the focusing drive coil 5 and is controlled so that the laser beam is always just focused on the optical disc 1.

The sum signal of the output of the tracking position sensor 8 in the state where focusing and tracking are performed as described above is
The unevenness of the pits (recorded information) formed on the track is reflected. This signal is supplied to the video circuit 19, where the signal is binarized and sent to the modulation / demodulation circuit 29. The image information demodulated by the modulation / demodulation circuit 29 and the block header information (track number, block number, sector number, etc.) as address information are sent to the error detection and correction circuit 30 and also to the address detection circuit 32. The error detection and correction circuit 30 checks whether or not the transmitted image information has an error. If there is an error, the error is corrected and stored in the data buffer 28 sequentially. The address detection circuit 32 detects the block header information and sends it to the CPU 23 via the bus line 20. CPU23,
It receives the block header information from the address detection circuit 32 and checks its validity.

The interface circuit 31 transmits and receives information to and from a host such as a computer.

Further, the tracking control circuit 16 moves the objective lens 6 in accordance with a track jump signal supplied from the CPU 23 via the D / A converter 22, and moves the beam light for one track. .

The laser control circuit 14, the focusing control circuit 15,
The tracking control circuit 16, the linear motor control circuit 17, the motor control circuit 18, the video circuit 19, and the like are controlled by a CPU 23 via a bus line 20.
23 performs a predetermined operation according to a program stored in the memory 24. The memory 24 is also used as a buffer for temporarily storing processing data.

In addition, the disk drive includes a focusing control circuit 15, a tracking control circuit 16, a linear motor control circuit
A used for exchanging information between 17 and CPU 23
A / D converter 21 and a D / A converter 22 are provided.

The tracking control circuit 16 amplifies the tracking error signal supplied from the differential amplifier OP1 with different gains during recording and reproduction according to the gain switching signal supplied from the CPU 23, and performs phase compensation. After that, the signal is further amplified and supplied to a drive circuit (not shown). This allows
The drive circuit performs tracking by driving the drive coil 4 according to the supplied signal.

The laser control circuit 14 includes the CPU 23 or the modem 2
The semiconductor laser 9 is driven in accordance with a signal supplied from the light source 9 to reproduce information by emitting light of low intensity and record information by emitting light of high intensity according to a recording pulse.

As shown in FIG. 4, the focus error detection circuit 33 includes an operational amplifier OP3 as a comparator, a D-type flip-flop FF, and resistors R1 to R3. Then, the focus error signal (focus error signal) FSUB from the focusing control circuit 15 is input to the inverting input of the comparator OP3, and the comparison voltage divided and generated by the resistors R1 and R2 is input to the non-inverting input. Has become. As the comparison voltage, a first comparison voltage th1 for detecting the upper level of the focus error signal and a second comparison voltage th2 for detecting the lower level of the focus error signal are generated by the resistors R1 and R2. Further, the comparison voltages th1 and th2
For example, if the focus error signal FSUB is
It is adjusted to output a voltage of ± 0.5 V if it has a characteristic of outputting a voltage of ± 1 V with respect to the above unevenness of 1 μm. The flip-flop FF is reset by the CLEAR signal from the CPU 23, and is set at the edge of the change of the pulse output from the comparator OP3.
Then, the set signal is sent to the CPU 23 as a defect signal FERR.

Next, a format check operation in such a configuration will be described. For example, now, the optical head 3 starts moving from the innermost circumference toward the outermost circumference, and the CPU 23
By driving the laser control circuit 14, the semiconductor laser 9 generates a weak laser beam.

As a result, the laser light is converted into a parallel light beam by the collimator lens 11a, reflected by the half prism 11b and made incident on the objective lens 6, and is focused toward the recording film of the optical disc 1 by the objective lens 6.

Then, the reflected light from the optical disc 1 is guided to the half prism 11c via the objective lens 6 and the half prism 11b. The light guided to the half prism 11c passes through the half prism 11c and is irradiated on the photodetector 8 through the condenser lens 10, and is reflected by the half prism 11c and passes through the condenser lens 11d. The light is irradiated onto the photodetector 7.

As a result, two detection signals corresponding to the irradiation light amount are output from the photodetector 8, the difference between them is obtained in OP1, and the tracking control circuit 15 performs tracking based on the difference (tracking error signal). (Track shift)
Make corrections.

Further, two detection signals corresponding to the irradiation light amount are output from the photodetector 7, the difference between them is obtained in OP2, and the focus control circuit 15 controls the focusing according to the difference (focus error signal). (Blur) correction.

After the optical head 3 is brought into the focused state and the focused track state, the reading of the address information recorded on the optical disk 1 is started.

That is, a signal, which is output from the tracking position sensor 8 and reflects the unevenness of the block header portion recorded on the track of the optical disk 1, is supplied to the video circuit 19, and is binarized by the video signal 19 to be modulated and demodulated. Sent to 29. After being demodulated by the modulation / demodulation circuit 29, it is sent to the address detection circuit 32, where the address detection circuit 32 checks whether or not there is an error in the information recorded in the block header. If an error in the block header is detected by the address detection circuit 32, information to that effect is sent to the CPU 23.
, And are sequentially stored in the memory 24.

On the other hand, the focus error signal from OP2 is supplied via the focusing control circuit 15 to the focus error detection circuit 33, that is, the inverting input terminal of the comparator OP3. Further, the above-described comparison voltage is supplied to the non-inverting input terminal of the comparator OP3, and the two inputs are constantly being compared. Here, if there is no defect in the data recording area of the track on the optical disc 1, that is, if there is no fine projection or dent or foreign matter adhered, the focus error signal when reproducing the area outputs a flat signal. However, if there is such a defect, the focus is instantly blurred, so that a signal that changes upward (plus direction) as shown in FIG. 5A is output. When the focus error signal FSUB based on the defect of the optical disc 1 is inputted to the comparator OP3, the output thereof has a pulse having a width of a portion protruding in the plus direction from the comparison voltage th1 as shown in FIG. A signal is output. The same applies to the case where a signal that changes in the downward direction (minus direction) is obtained as the focus error signal FSUB. In this case, the pulse having the width of the portion protruding in the minus direction from the comparison voltage th2 is used. A pulse signal having a phase opposite to that of the signal is output. The flip-flop FF is set by the edge where these signals change (see FIG. 3C), and the defect signal FERR is output. Then, the CPU 23 that has received the defect signal FERR stores information indicating that in association with the block header information at that time in the memory 24,
The EAR signal is output to reset the flip-flop FF (see (d) in the figure), and the process proceeds to the next block check.

As described above, in parallel with reproducing the block header and checking its validity, the presence or absence of defects in the data recording area of the block is checked, and if there is any abnormality, information on the defect is sequentially stored in the memory 24. I will remember. When the checking of the entire area from the innermost circumference to the outermost circumference is completed, the defect information stored in the memory 24 is replaced with a maintenance track provided in an area other than the user area on the outer or inner circumference of the optical disc 1. And the processing of the format check ends.

The defect information written on the maintenance track of the optical disk 1 as described above is read out when the optical disk 1 is next recorded or reproduced, and when the block is accessed, the block is replaced with the block. Thus, a so-called spare track process for accessing a separately prepared spare track is performed. As a result, information can be recorded or reproduced while avoiding a block having a defect, and the user can handle the optical disk 1 as if it had no defect.

As described above, in the format check, in addition to the validity check of the address information, if the focus error signal during reproduction of the data recording area becomes other than the predetermined level, the block has a defect. Is detected, and the defect information, which is the result of this detection, is written to the maintenance track of the optical disk. Therefore, despite the simple configuration, the optical disk defect can be detected. By performing the track processing, it can be handled as if it were an optical disk having no defect.

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to reliably detect the presence of a defect in the data recording area together with the validity of the address information of the optical disc during the format check,
It is possible to provide an optical disk device that can record or reproduce data normally.

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a diagram showing the structure of a disk drive, FIG. 2 is a diagram showing the structure of an optical disk, FIG. 3 is a diagram showing the structure of a block, and FIG. FIG. 5 is a block diagram for explaining a configuration of a main part of the circuit, and FIG. 5 is a diagram showing timing signals of respective parts at the time of detecting a defect. DESCRIPTION OF SYMBOLS 1 ... Optical disk, 2 ... Rotary motor, 3 ... Optical head, 4 ... Driving coil, 6 ... Objective lens (condensing means), 7 ... Focus position sensor, 8 ... Tracking position sensor, 9 ... ... Semiconductor laser, OP2 ... Differential amplifier, 14 ... Laser control circuit, 15 ... Focusing control circuit, 19 ... Video circuit, 23 ... CPU (control means), 24 ...
... memory (storage means), 29 ... modulation / demodulation circuit (reading means), 32 ... address detection circuit (first detection means), 33
... Focus error signal detection circuit (second detection means).

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-113137 (JP, A) JP-A-59-688218 (JP, A) JP-A-60-69865 (JP, A) JP-A-63-1988 58669 (JP, A) JP-A-63-48662 (JP, A) JP-A-61-271532 (JP, A) JP-A-63-63168 (JP, A)

Claims (2)

(57) [Claims] 1. An optical disc apparatus for recording data on an optical disc which is recorded in a block unit including a header area and a data recording area, wherein the header area and the data area are arranged continuously. Focusing means for irradiating the recording area with a light beam weaker than the level at which data is recorded; reading means for reading address information from the header area for each block irradiated with the light beam by the focusing means; A first detecting means for detecting a defect in the header area of each block from the address information read in the step (a), and a light beam irradiated by the light condensing means so as to be continuously detected by the first detecting means. A defect in a data recording area of each block is detected by a focus error signal indicating a focus state on the optical disc. A second detection unit, and a detection result of the defect detected by the second detection unit and the first detection unit, the block including the header area or the data recording area in which the defect is detected, A storage unit for temporarily and sequentially storing the information as defect information in association with the address information by the reading unit, and for all areas of the plurality of blocks on the optical disc,
After the detection of the defect by the first and second detection means is completed, control is performed to record the defect information of all the blocks temporarily and sequentially stored in the storage means in a predetermined maintenance area on the optical disk. An optical disk device comprising: a control unit that performs the control. 2. A write-once optical disc which is recorded in a block unit including a header area and a data recording area, wherein data is recorded on a write-once optical disc in which the header area and the data area are continuously arranged. In an optical disk device, a light-collecting means for irradiating a light beam weaker than a level at which data is recorded on the data recording area, and reading for reading address information from a header area of each block irradiated with the light beam by the light-collecting means Means, a first detecting means for detecting a defect in the header area for each block from the address information read by the reading means, and a condensing means so as to continue the detection by the first detecting means. Data recording for each block is performed by a focus error signal indicating a focus state of the irradiated light beam on the write-once optical disc. Second to detect defects in the area
Detecting means for detecting a defect detected by the second detecting means and the first detecting means, and reading the block including a header area or data recording area where the defect is detected by the reading means. Storage means for temporarily and sequentially storing as defect information in association with the address information; and detection of defects by the first and second detection means for all areas of a plurality of blocks on the write-once optical disc. After completion of, control means for controlling the recording of the defect information of all the blocks temporarily sequentially stored in the storage means in a predetermined maintenance area on the write-once optical disc, Characteristic optical disk device.