JP2005149670A - Information recording and reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correctly detect address information irrespective of whether or not recording has been made on the right and left of a track from which the address information is desired to detect. <P>SOLUTION: Since it becomes possible to correctly extract an address superimposed on a wobble signal by adjusting the output signals from adders 42, 43 of which the levels vary according to whether or not the signal obtained from an optical disk 11 is a recorded or unrecorded signal, a wobble address can be detected correctly irrespective of whether or not the adjacent tracks are recorded. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an information recording / reproducing apparatus in which recording can be performed on both lands and grooves, and address information is managed by wobble.

When performing conventional servo servo control or focus servo control, a conventional information recording apparatus adds a predetermined offset amount to the tracking error signal or focus error signal to adjust the control balance of servo control, for example, a reproduction signal, a wobble signal, etc. The jitter is made smaller. (For example, Patent Document 1)
JP 2002-216379 A (Page 4, FIG. 4)

  The technique of the above-described Patent Document 1 mainly adjusts the offset only at the time of manufacturing or shipping. The offset adjustment is set to the minimum value of the jitter of the wobble signal, but is not seen from the viewpoint of the recording state and the unrecorded state of the information recording medium. For this reason, when performing address information detection, if recording is performed only on one adjacent track, a difference in light quantity occurs due to the difference in reflectance between the unrecorded part and the recorded part. Problems such as a loss of balance and erroneous detection of a wobble address signal detected by a difference signal have been newly found.

  An object of the present invention is to provide an information recording / reproducing apparatus capable of accurately detecting address information regardless of whether or not recording is performed on the left and right of a track for which address information is desired to be detected.

  In order to solve the above-described problems, the information recording / reproducing apparatus of the present invention can record information on both the land and the groove of the optical disk and record information on the optical disk whose address information is managed by wobble. A light detecting means for reproducing, having a light receiving surface A to D divided in a radial direction and a track direction of the optical disc for irradiating the optical disc with a light beam and receiving reflected light from the optical disc A first adder that obtains a first sum signal from the signals output from the light receiving surfaces A and B of the light detecting means, and a signal output from the light receiving surfaces C and D of the light detecting means. A second adder for obtaining a second sum signal; a determination means for determining whether the first and second sum signals are recorded or unrecorded; and a determination result of the determination means. Characterized by comprising an adjustment means for adjusting the balance of the difference signal between the first and second sum signals.

  According to the present invention, by reproducing the address by changing the reproduction circuit constant, it is possible to accurately reproduce the address regardless of whether the track before and after the track on which the address is reproduced is recorded or not recorded.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a system configuration diagram for explaining an information recording / reproducing apparatus used in the present invention. Reproduction processing for reading out information stored in the optical disc 11 as a recording medium, decoding processing and reproduction, and / or video signal, sub-video signal, and audio signal are received, and encoding processing is performed. 1 shows a disk device 100 that performs a recording process for recording into a disk.

  The optical disk 11 is mounted on the disk drive unit 12. The disk drive unit 12 drives and rotates the mounted optical disk 11 to read and decode information stored on the optical disk 11 using an optical pickup or the like, and / or reproduce information according to the encoded signal. It is recorded on an information recording medium.

  Hereinafter, a disk device related to reproduction processing will be described.

  Information read by the disk drive unit 12 is supplied to an MPU (Micro Processing Unit) unit 13, subjected to error correction processing, and then stored in a buffer (not shown). Of this information, management information for the control data area Is recorded in the memory unit 14 and used for reproduction control, data management, and the like.

  Of the information stored in the buffer, the video object area information is transferred to the separation unit 15 and separated for each of the main video pack MVP, the audio pack AP, and the sub-video pack SVP. The information of the main video pack MVP is supplied to the video decoder unit 16, the information of the audio pack AP is supplied to the audio decoder unit 17, and the information of the sub video pack SVP is supplied to the sub video decoder unit 18 for decoding. The main video information decoded by the video decoder unit 16 and the sub-video information decoded by the sub-video decoder unit 18 are supplied to the D-processor unit 19 and subjected to superposition processing, and then D / A (Digital / Analogue) The analog signal is converted by the conversion unit 20, and the sub-video information is converted into the analog signal by the D / A conversion unit 21 and output as a video signal to a video display device such as a CRT (Cathode Ray Tube) (not shown). . The audio information decoded by the audio decoder unit 17 is converted into an analog signal by the D / A converter 22 and output as an audio signal to a speaker or the like (not shown).

  A series of playback operations on the optical disc 11 as described above are controlled in an integrated manner by the MPU unit 13. The MPU unit 13 receives operation information from the key input unit 23 and controls each unit based on a program stored in a ROM (Read Only Memory) unit 24.

  The recording process will be described. Each data input through the video, audio, and sub-video input terminals is supplied to the A / D converters 25, 26, and 27, and converted from analog signals to digital signals. The video data digitally converted by the A / D converter 25 is supplied to the video encoder 28 and encoded. The sub video data digitally converted by the A / D converter 26 is supplied to the sub video encoder 29 and encoded. The audio data digitally converted by the A / D conversion unit 27 is supplied to the audio encoder unit 30 and encoded.

  The video, audio, and sub-picture data encoded by each encoder are supplied to a multiplexing unit (MUX: Multiplexer) 31, and are respectively packetized and packed into an MPEG-2 program stream as a video pack, audio pack, and sub-picture pack. Configure. The multiplexed data group is supplied to the file formatter unit 32 and converted into a file conforming to a file structure that can be recorded and reproduced by the disk device. This file is supplied to the volume formatter unit 33 to form a data format conforming to a volume structure that can be recorded and reproduced by the disk device. Here, data filed by the file formatter unit 32, reproduction control information for reproducing the filed data, and the like are added. Thereafter, the data is supplied to the physical formatter 34 and the disk drive unit 12 records the filed data on the optical disk 11.

  Such reproduction and recording operations are performed by being executed by the MPU unit 13 under the instruction from the key input unit 23 based on a series of processing programs stored in the ROM unit 24 of the disk device. Is.

  In this disk device, both the encoding process and the decoding process of the sub-picture data are performed. However, only the encoding process is performed by the authoring system or the like, or only the decoding process is performed by the disk device. It is also possible.

  The optical disk device operates with reference to the logical format of the optical disk 10. In the optical disk 10, the volume space from the lead-in area to the lead-out area has the volume and file structure as described above. This structure is a specific standard as a logical format, for example, a subset of ISO 13346, and is a general-purpose disk file format proposed by the Optical Storage Technology Association (OSTA) for the purpose of data portability and ease of implementation. It is defined in conformity with UDF (Universal Disk Format) and ISO9660. As described above, the volume space is physically divided into a plurality of sectors, and serial numbers are assigned to the physical sectors. The logical address means the logical sector number LSN as defined by the micro UDF and ISO 9660, the logical sector is 2048 bytes as well as the size of the physical sector, and the logical sector number LSN is in ascending order of the physical sector number. A serial number is added.

  Here, the optical disk 11 is composed of four areas of a system lead-in area, a data lead-in area, a data area, and a data lead-out area where the track pitch is wider than other areas and pits are formed. The optical disc 11 includes at least a substrate and a recording layer. The substrate has a groove and a land, and each groove has a continuous spiral. The groove has a wobble having a constant frequency.

  In this wobble, address information is recorded by modulating a signal as shown in FIG. The wobble in which the address information is recorded is described in Japanese Patent Application No. 2003-95403 filed earlier by the present applicant.

  FIG. 3 is a block diagram for explaining an embodiment of the present invention. In FIG. 3, the optical disk 11 is configured to read information recorded on the optical disk 11. The optical disk 11 is irradiated with a light beam, and the reflected light is reflected by a four-divided photodetector 41. The sum of A and B and C and D of the photodetector 41 is obtained by the adders 42 and 43, respectively. An adder 44 obtains an addition output from the outputs of the adders 42 and 43. Also, the subtractor 46 obtains the subtraction of the output from the adder 42 through the variable amplifier 45 and the output from the adder 43.

  Further, the output of the adder 42 is supplied to the averaging circuit 47. In the averaging circuit 47, the absolute value of the sum of A and B of the photodetector 41 is averaged, the comparator 48 compares the absolute value with the reference value, and whether the adjacent track is recorded by the determination unit 49 based on the comparison result. Make a decision. Similarly, the averaging circuit 50 averages the absolute value of the sum of C and D of the photo detector 41, compares it with the reference value by the comparator 51, and records the adjacent track in the determining unit 50 based on the comparison result. It is determined whether or not

Assuming that 1 is larger than the reference value and 0 is smaller, the combinations of (A + B) and (C + D) are 0, 0, 0, 1, 1, 0, 1, 1, as shown in FIG. Exists. Since the combinations of 0, 0, 1, and 1 are balanced between (A + B) and (C + D), the same preset α0 may be used. When the combination is 0, 1, the preset α2, α1, α0 is used.

  The determination result of the determination unit 49 is supplied to the switching device 52, and the amplification degree of the variable amplifier 45 is determined based on the switching result. The variable amplifier 45 is provided with presets α0, α1, and α2, and the presets are switched by determining whether the adjacent track is in an unrecorded state or a recorded state.

  As an example, by setting the amplification factors of α0, α1, and α2 in a relationship of α2 <α0 <α1, by selecting an amplification factor based on the determination result of the determination unit 49, an unrecorded or recorded state of an adjacent track The output suitable for can be obtained.

  According to this embodiment, it is possible to accurately extract the address superimposed on the wobble signal by adjusting the output signal from the adders 42 and 43 whose level varies depending on whether it is unrecorded or recorded. Therefore, the wobble address can be accurately detected regardless of whether the adjacent track is unrecorded or recorded.

  In this embodiment, three types of presets are prepared. However, the present invention is not limited to this, and in order to obtain better address reproduction conditions, more than three types of presets may be prepared and used.

  In the above-described embodiment, the preset of the amplifier is used to balance the photodetector. However, it is also possible to perform optimization by adjusting the amplifier each time the address cannot be read instead of the preset.

This specific example will be described with reference to FIG. 5 as another embodiment. First, the wobble address is reproduced using the preset α0 (S1). At that time, the error rate of the address is measured (S2), and the threshold of the error rate is set to 1 × 10 ⁻⁴ , for example, which is bad when the value is larger than this. If it is worse than this threshold, the wobble address is reproduced again using the preset α1 (S3). The error rate is measured (S4). If the error rate is still worse than the threshold value, the wobble address is reproduced using the preset α2 (S5). If the error rate is still bad (S6), this time, the offset amount of the amplifier is changed (S7), this flow is repeated again, and when the error rate becomes better than the threshold value, recording and reproduction are performed using this preset. (S8).

  Also in this embodiment, by reproducing the address information by changing the constant, it is possible to accurately reproduce the address regardless of whether the track before and after the track on which the address is reproduced is recorded or not recorded.

  The present invention is not limited to the embodiments described above. For example, when actually setting a preset, the preset may be unique to the entire system, the preset value may be changed for each model, or may be set at the time of manufacture and shipment for each information recording / reproducing apparatus. However, it may be set at the time of calibration for each optical disc.

In addition, when selecting a preset, the judgment was made based on the balance of (A + B) and (C + D) of the photodetector. However, the present invention is not limited to this. From this information, the recording state of the left and right tracks at the location where address reproduction is actually desired may be recognized, and a preset may be selected based on this information. Further, although the amplifier is attached only to (A + B), it is not limited to this, and it may be attached only to (C + D) or both (A + B) and (C + D). Furthermore, although a rewritable recording information medium is used, the present invention is not limited to this, and the same effect can be obtained even if a recording information medium is used only once.

The block diagram for demonstrating the information recording / reproducing apparatus used for this invention. Explanatory drawing for demonstrating the wobble signal used for this invention. The block diagram for demonstrating one Example of this invention. Explanatory drawing for demonstrating the operation | movement of FIG. Explanatory drawing for demonstrating the other Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Optical disk 12 Disk drive part 41 Photo detector 42,43,44 Adder 45 Variable amplifier 46 Subtractor 47,50 Average circuit 48,51 Comparator 49 Judgment part 52 Switch

Claims (4)

In an information recording / reproducing apparatus for recording / reproducing information on / from an optical disk in which address information is managed by wobble, while recording can be performed on both lands and grooves of the optical disk.
A light detection means having light receiving surfaces A to D divided in a radial direction and a track direction of the optical disc for irradiating the optical disc with a light beam and receiving reflected light from the optical disc;
A first adder for obtaining a first sum signal from the signals output from the light receiving surfaces A and B of the light detection means;
A second adder for obtaining a second sum signal from the signals output from the light receiving surfaces of C and D of the light detection means;
Determining means for determining whether the first and second sum signals are in a recorded or unrecorded state;
An information recording / reproducing apparatus comprising: an adjusting unit that adjusts a balance of a difference signal between the first and second sum signals based on a determination result of the determining unit. The determination means averages the absolute value of the output of the first adder and compares it with a reference value, and also averages the absolute value of the output of the second adder and compares it with a reference value. The information recording / reproducing apparatus according to claim 1, wherein: There is an amplifier between the amount of light detected by the light detection means until the difference signal is generated, and there are a plurality of presets for adjusting the amplifier, and when reproducing the address using the difference signal, the adjacent track is 2. The information recording / reproducing apparatus according to claim 1, wherein the preset is switched to an optimum preset depending on whether or not recording is performed. When switching presets, the management file of the optical disc is reproduced in advance, the recorded location is recognized, it is determined whether or not the adjacent track is recorded based on the recognition information, and the preset is switched. The information recording / reproducing apparatus according to claim 2.

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