JP5640251B2 - Optical disc inspection apparatus and optical disc inspection method - Google Patents

Description

  The present invention relates to an optical disc inspection apparatus and an optical disc inspection method, and more particularly to a technique for discriminating between copy guards and defects of an optical disc.

  2. Description of the Related Art Conventionally, there has been known an optical disc inspection apparatus that inspects an optical disc by measuring the number of errors in reproduction data and an error rate.

  The following Patent Document 1 discloses a feed unit that moves the irradiation position of a laser beam in the radial direction of the optical disc relative to the optical disc, a defect position detection unit that detects a position of a defect portion on the recording surface of the optical disc, and a defect position. An optical disc inspection apparatus having inspection radius position setting means for setting a radius position when measuring the number of errors or error rate in reproduction data based on the radius of the defect position detected by the detection means is disclosed.

JP 2008-165846 A

  However, in recent years, optical disks with so-called copy guards to prevent illegal copying of optical disks have been supplied to the market. For example, as disclosed in Japanese Patent No. 3449804, the copy guard does not execute reproduction data obtained by executing error correction processing using an error correction code to reproduce user data and error correction processing using an error correction code. So that bit data that can be corrected with an error correction code is generated by partially switching the logic level of the recorded data string so that it can be detected by comparison with reproduced data obtained by reproducing user data in Data is recorded.

  When an inspection device inspects an optical disc that has been subjected to such copy guard, an error occurs in the reproduction data even in the copy guard portion. Therefore, in the inspection device that determines the presence or absence of a defect based on the error number or error rate of the reproduction data, Even if there are no physical defects such as scratches and dirt that should be detected originally, the optical disc is erroneously determined to be defective.

  In particular, optical discs such as DVDs that record content such as movies may be inspected by an inspection device for defects in the optical discs when they are brought into a rental store. This affects the reliability of the inspection device.

  An object of the present invention is to provide an apparatus and a method capable of inspecting an optical disk by reliably identifying the copy guard and a defect even if the optical disk has been subjected to copy guard.

The present invention is an optical disc inspection apparatus, wherein the optical disc is a multilayer optical disc including at least a first layer and a second layer, and first reproducing means for reproducing data of the first layer;
A first detecting means for detecting that a reproduction error or an error rate has deteriorated during data reproduction of the first layer; and a second detector at the same radial position when the reproduction error or the error rate has deteriorated. Second reproduction means for reproducing layer data, second detection means for detecting that a reproduction error or an error rate has deteriorated during data reproduction of the second layer, and reproduction error or When the deterioration of the error rate is detected, it is determined that the optical disk has a physical defect, and the reproduction error detected by the first detection unit when the reproduction error or the deterioration of the error rate is not detected by the second detection unit Alternatively , a determination unit that determines that the deterioration of the error rate is caused by copy guard is provided.

The present invention is also an optical disc inspection apparatus, wherein the optical disc is a multilayer optical disc including at least a first layer and a second layer, and a first reproducing unit that reproduces data of the first layer; First detection means for detecting that a reproduction error or an error rate has deteriorated during data reproduction of the first layer, and a storage means for storing the position when the reproduction error or the error rate has deteriorated; A second reproducing means for reproducing the data of the second layer corresponding to the position stored in the storage means after the data reproduction of the first layer is completed, and at the time of reproducing the data of the second layer A second detection means for detecting that a reproduction error or a deterioration in the error rate has occurred; and when the reproduction error or a deterioration in the error rate is detected by the second detection means, it is determined that the optical disk has a physical defect. The above And characterized in that it comprises a determining means, the reproduction deterioration of error or a reproduction error or error rate deterioration of the error rate detected by said first detecting means does not detect is by copy guard 2 detector To do.

The present invention also relates to an optical disc inspection method, wherein the optical disc is a multilayer optical disc including at least a first layer and a second layer, and one of the first layer and the second layer. And a first detection step for detecting whether or not a reproduction error or an error rate deterioration occurs, and reproduction at the same radial position of the other one of the first layer and the second layer. A second detection step for detecting whether or not an error or an error rate deteriorates; and if a reproduction error or an error rate deterioration occurs in the second detection step, it is determined that the optical disk has a physical defect. and, deterioration of reproduction error or error rate detected by said first detection step when no occur and; and a determination step to be due to the copy guard That.

  According to the present invention, the optical disk can be inspected by reliably identifying the copy guard and the defect of the optical disk.

1 is an overall configuration diagram of an embodiment. It is a sector block diagram of a two-layer optical disk. It is a flowchart of an inspection process. It is another flowchart (the 1) of inspection processing. It is another flowchart (the 2) of inspection processing. It is another flowchart of an inspection process.

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

  FIG. 1 shows the overall configuration of an optical disk inspection apparatus according to this embodiment. The optical disk 10 to be inspected is driven by a spindle motor (SPM) 12. The SPM 12 is driven by a driver 14, and the driver 14 is servo-controlled by a servo processor 30 so as to have a desired rotation speed.

  The optical pickup 16 includes a laser diode (LD) for irradiating the optical disk 10 with laser light and a photodetector (PD) that receives reflected light from the optical disk 10 and converts it into an electrical signal, and is disposed opposite to the optical disk 10. . The optical pickup 16 is driven in the radial direction of the optical disk 10 by a sled motor 18 constituted by a stepping motor, and the sled motor 18 is driven by a driver 20. The driver 20 is servo-controlled by the servo processor 30 similarly to the driver 14. The LD of the optical pickup 16 is driven by a driver 22, and the driver 22 is controlled by an auto power control circuit (APC) 24 so that the drive current becomes a desired value.

  The APC 24 and the driver 22 control the light emission amount of the LD according to a command from the system controller 32. Although the driver 22 is provided separately from the optical pickup 16 in the figure, the driver 22 may be mounted on the optical pickup 16.

  When the optical disk 10 is inspected for defects, a laser beam of reproduction power is irradiated from the LD of the optical pickup 16, and the reflected light is converted into an electrical signal by the PD and output. A reproduction signal from the optical pickup 16 is supplied to the RF circuit 26.

  The RF circuit 26 generates a focus error signal and a tracking error signal from the reproduction signal and supplies them to the servo processor 30. The RF circuit 26 supplies an address signal included in the reproduction signal to the address decoding circuit 28 and supplies the reproduction RF signal to the binarization circuit 34.

The servo processor 30 servo-controls the optical pickup 16 based on these error signals, and maintains the optical pickup 16 in an on-focus state and an on-track state.
The address decoding circuit 28 demodulates the address data of the optical disk 10 from the address signal and supplies it to the servo processor 30 and the system controller 32.

  The binarization circuit 34 binarizes the reproduction signal and supplies the obtained signal to the decoding circuit 36. The decoding circuit 36 demodulates the binary signal and corrects errors to obtain reproduction data, and temporarily stores the reproduction data in the buffer memory 38. The reproduction data stored in the buffer memory 38 is appropriately read and supplied to the system controller 32. Further, the decoding circuit 36 outputs the number of errors or the error rate to the system controller 32.

  The system controller 32 controls the operation of the entire system, drives the sled motor 18 via the servo processor 30, and controls the position of the optical pickup 16. Further, the system controller 32 determines the presence / absence of a defect in the optical disc 10 based on the number of errors or the error rate supplied from the decoding circuit 36, and outputs the determination result to an external display. However, as described above, when the optical disk 10 is a copy guarded optical disk, a reproduction error or an error rate deteriorates also in the copy guard part. It is impossible to identify whether there is a reproduction error due to a physical defect that should be detected or a deterioration in error rate.

  Therefore, in the present embodiment, when the optical disc 10 is a two-layer or other multilayer optical disc, a reproduction error or an error rate deterioration due to copy guard occurs only in a specific layer, while in the case of a physical defect, a specific error occurs. Focusing on the fact that not only the layer but also other layers (all layers) occur in the same way, using this fact, reproduction error or error rate deterioration due to copy guard and reproduction error or error rate due to physical defects It distinguishes from worsening.

  FIG. 2 shows a physical and logical layer configuration of a two-layer optical disk as an example of a multilayer optical disk. FIG. 2A shows an optical disc (PTP: Parallel Track Path Disc) in which the sector order of the layer 0 layer (L0) and the layer 1 layer (L1) is the same direction (from the inner periphery toward the outer periphery). b) An optical disc (OTP) in which the sector order of the layer 0 layer (L0) and the layer 1 layer (L1) is opposite to each other (the layer 0 layer is directed from the inner periphery to the outer periphery, and the layer 1 layer is directed from the outer periphery to the inner periphery). : Opposite Track Path Disc).

  In any optical disc, since each layer is arranged on one board surface, the optical disc inspection apparatus reproduces only the layer 0 layer (L0), measures the reproduction error, and checks whether there is a physical defect. Determine. In a copy guarded optical disk, normally, a sector of data that cannot be reproduced is embedded in the layer 0 layer (L0). Therefore, when this sector is reproduced, a reproduction error or an error rate deteriorates, resulting in a physical defect. It will be misjudged.

  However, since there is no copy guard in the layer 1 layer (L1), even if a playback error occurs in the layer 0 layer, the playback error or error rate in the sector of the layer 1 layer (L1) corresponding to the sector. Can be played back without any problem. On the other hand, when there is a physical defect, the reproduction error or the error rate deteriorates in the layer 0 layer, and the reproduction error or the error rate also deteriorates in the layer 1 layer sector corresponding to the sector. Arise.

  Therefore, the system controller 32 of this embodiment jumps to the layer 1 layer when a reproduction error or an error rate deteriorates in the reproduction of the layer 0 layer, and corresponds to the sector in which the reproduction error or the error rate deteriorates. If the sector 1 layer sector is reproduced without any problem, the layer 0 layer reproduction error is not regarded as a physical defect because it is caused by copy guard. On the other hand, when the reproduction error or the error rate deteriorates also in the layer 1 layer, it is determined that the reproduction error or the error rate deterioration of the layer 0 layer is surely due to a physical defect.

  As described above, in the present embodiment, when the reproduction error or the error rate deteriorates only in the layer 0 layer using the characteristics of the multilayer optical disc, the physical defect is not regarded as a physical defect. Therefore, it is possible to effectively prevent an optical disc with copy guard from being erroneously determined as an optical disc having a physical defect. Whether or not the error rate has deteriorated can be determined by comparing the error rate with a predetermined threshold value. When the error rate increases beyond the predetermined threshold value, the error rate deteriorates. It is determined that it has occurred.

  FIG. 3 shows a flowchart of the inspection process in the present embodiment. First, inspection (check) of the layer 0 layer (L0: Layer 0) is started from the inner periphery side (S101).

  Next, the system controller 32 determines based on the signal from the decoding circuit 36 whether a reproduction error has occurred or whether the error rate has deteriorated beyond an allowable value (S102).

  When a reproduction error occurs (including the case where the number of errors exceeds a predetermined value) or when the error rate deteriorates, the system controller 32 drives the optical pickup 16 to set the irradiation position of the laser beam to layer 0. The layer 1 moves to the layer 1 layer, and the layer 1 layer (L1: Layer 1) at the same radius position is reproduced (S103). Then, it is determined whether a reproduction error has occurred in the layer 1 or whether the error rate has deteriorated (S104).

  When a reproduction error occurs in the layer 1 layer as well as in the layer 0 layer, or when the error rate deteriorates, the system controller 32 determines that the optical disk 10 to be inspected has a defect (S105). . If it is determined that there is a defect, the inspection ends at that time.

  On the other hand, if no reproduction error occurs in the layer 1 layer, the system controller 32 regards the reproduction error in the layer 0 layer not as a physical defect but as a copy guard, and again picks up the optical pickup assuming that there is no physical defect. 16 is driven to move the irradiation position of the laser beam from the layer 1 layer to the layer 0 layer. Then, it is determined whether or not the inspection of the entire circumference of the layer 0 layer has been completed (S106). If the inspection of the entire circumference has not been completed, the reproduction and check of the layer 0 layer are resumed (S107). The processes after S102 are repeated until the entire circumference is inspected. When the inspection of the entire circumference is completed, the optical disk 10 to be inspected is normally terminated assuming that there is no physical defect (S108).

In this embodiment, when a playback error occurs during playback of the layer 0 layer, the layer 1 layer is played back at that point in time, but a playback error occurs during playback of the layer 0 layer. Alternatively, the radius position where the reproduction error occurs may be stored, the entire circumference of the layer 0 layer may be inspected as it is, and then the corresponding radial position of the layer 1 layer may be reproduced.
4 and 5 show a flowchart of the inspection process in this case. First, inspection of the layer 0 layer (L0) is started from the inner periphery side (S201).

  Next, the system controller 32 determines, based on the signal from the decoding circuit 36, whether a reproduction error has occurred or whether the error rate has deteriorated beyond an allowable value (S202).

  When a reproduction error occurs (including the case where the number of errors exceeds a predetermined value) or when the error rate deteriorates, the system controller 32 holds the address of that position in the memory (S203). Then, it is determined whether or not the inspection of the entire circumference of the layer 0 layer has been completed (S204). If the inspection of the entire circumference has not been completed, the reproduction and check of the layer 0 layer are resumed (S210). The processes after S202 are repeated until the inspection of the entire circumference is completed.

  After the inspection of the entire circumference of the layer 0 layer is completed, it is determined whether or not there is a reproduction error of the layer 0 layer (S205). When a reproduction error occurs, the address is held in the memory. When the address is not held in the memory, the inspection is normally terminated as a reproduction error has not occurred in the layer 0 layer (S212). ). In other words, the optical disc 10 to be inspected is determined as a normal optical disc without defects. If a reproduction error has occurred in layer 0, the process proceeds to FIG.

  In FIG. 5, the system controller 32 calculates the address of the layer 1 layer having the same radius as the layer 0 layer by using the address held in the memory, and drives the optical pickup 16 to set the irradiation position of the laser beam to the layer 0. The reproduction is resumed by moving from the layer 1 to the layer 1 (S206). Then, it is determined whether a reproduction error has occurred in layer 1 or whether the error rate has deteriorated (S207). When a reproduction error occurs in the layer 1 layer as well as in the layer 0 layer, or when the error rate deteriorates, it is determined that the optical disk 10 to be inspected is defective and the inspection process is terminated (S209). If a reproduction error does not occur in the layer 1 layer, it is confirmed whether another address is held in the memory (S208), and if held, an error detection address of the layer 0 layer is acquired (S211). ) Repeat the same process. The processing of S206 to S211 is repeated until the check is completed for all addresses held in the memory. For all addresses, if no reproduction error occurs in the layer 1 layer, the layer 0 layer reproduction error is due to copy guard and not due to a physical defect, and the processing ends normally with no physical defect.

  As described above, in the present embodiment, even when a reproduction error occurs in the layer 0 layer, if no reproduction error occurs in the corresponding position in the layer 1 layer, it is determined that it is not a physical defect. It is possible to reliably identify physical defects from copy guards.

  As described above, since the copy guard is often embedded only in the layer 0 layer, it can be considered that the inspection apparatus inspects from the layer 1 layer.

  FIG. 6 shows a flowchart of the inspection process in this case. First, the system controller 32 determines whether the optical disk 10 to be inspected is PTP or OTP (S301). In the case of OTP, since the sectors are arranged from the outer periphery to the inner periphery of the layer 1 layer (L1), the inspection is started from the outer periphery of the layer 1 layer (L1) (S302). Since the sectors are arranged from the inner periphery toward the outer periphery, the inspection is started from the inner periphery of the layer 1 layer (L1) (S303).

  The addresses to be inspected are sequentially updated and inspected (S304), and it is determined whether a reproduction error has occurred or whether the error rate has deteriorated (S305). When a reproduction error occurs or the error rate deteriorates, the system controller 32 drives the optical pickup 16 to move the laser light irradiation position from the layer 1 layer to the layer 0 layer, and the same radius of the layer 0 layer The position is reproduced (S306), and it is determined whether a reproduction error has occurred in the layer 0 layer or the error rate has deteriorated (S307).

  If a reproduction error has occurred in both the layer 1 layer and the layer 0 layer or the error rate has deteriorated, it is determined that the optical disk 10 to be inspected is defective and the inspection is terminated (S308).

  On the other hand, if there is no playback error in the layer 1 layer, and if there is no playback error in the same radius position of the layer 0 layer even if a playback error has occurred in the layer 1 layer, it is not a physical defect. It is considered. The above processing is repeatedly executed for the entire circumference of the layer 1 layer (S309). As a result of inspecting the entire circumference of the layer 1 layer, if a reproduction error has not occurred or if a reproduction error has not occurred at the same radial position of the layer 0 layer, a physical defect It is determined that there is no normal optical disc, and the inspection is terminated.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this, A various deformation | transformation is possible.

  For example, in the inspection flowchart of FIG. 6, when a reproduction error occurs in the layer 1 layer, it is determined whether or not the reproduction error occurs by moving to the layer 0 layer. In addition, after the data reproduction of the layer 1 layer is completed in the entire circumference, it may be determined whether or not a reproduction error occurs by reproducing the data at the corresponding radial position of the layer 0 layer.

  In short, a two-layer optical disk may be a first layer and a second layer, and inspection may be started from the first layer, and the first layer may be the layer 0 layer (L0), or the first layer. May be layer 1 (L1).

  Further, in the present embodiment, a two-layer optical disc is specifically exemplified, but a multi-layer optical disc having three or more layers can be similarly inspected. For example, in the case of a three-layer optical disc, when a reproduction error occurs in the layer 0 layer, the layer 1 layer or the layer 3 layer at the same radius position, or the layer 1 layer and the layer 3 layer at the same radius position are reproduced. If it does not occur, it can be determined that it is due to copy guard and not a defect.

  10 optical disc, 16 optical pickup, 32 system controller.

Claims (5)

An optical disk inspection device,
The optical disc is a multilayer optical disc comprising at least a first layer and a second layer;
First reproducing means for reproducing the data of the first layer;
First detection means for detecting that a reproduction error or an error rate deterioration has occurred during data reproduction of the first layer;
Second reproduction means for reproducing the data of the second layer at the same radial position when the reproduction error or the error rate deteriorates;
Second detection means for detecting that a reproduction error or a deterioration in error rate has occurred during data reproduction of the second layer;
When the second detection unit detects a reproduction error or a deterioration in the error rate, it determines that the optical disk has a physical defect, and when the second detection unit does not detect a reproduction error or a deterioration in the error rate, Determining means for determining that the reproduction error or the error rate deterioration detected by the first detecting means is caused by copy guard ;
An optical disc inspection apparatus comprising: An optical disk inspection device,
The optical disc is a multilayer optical disc comprising at least a first layer and a second layer;
First reproducing means for reproducing the data of the first layer;
First detection means for detecting that a reproduction error or an error rate deterioration has occurred during data reproduction of the first layer;
Storage means for storing the position when the reproduction error or the error rate deteriorates;
Second reproduction means for reproducing the data of the second layer corresponding to the position stored in the storage means after the data reproduction of the first layer is completed;
Second detection means for detecting that a reproduction error or a deterioration in error rate has occurred during data reproduction of the second layer;
When the second detection unit detects a reproduction error or a deterioration in the error rate, it determines that the optical disk has a physical defect, and when the second detection unit does not detect a reproduction error or a deterioration in the error rate, Determining means for determining that the reproduction error or the error rate deterioration detected by the first detecting means is caused by copy guard ;
An optical disc inspection apparatus comprising: In the optical disk inspection apparatus according to any one of claims 1 and 2,
The optical disc inspection apparatus, wherein the first layer is a layer 0 (L0) layer, and the second layer is a layer 1 (L1) layer. In the optical disk inspection apparatus according to any one of claims 1 and 2,
The optical disc inspection apparatus, wherein the first layer is a layer 1 (L1) layer, and the second layer is a layer 0 (L0) layer. An optical disc inspection method,
The optical disc is a multilayer optical disc comprising at least a first layer and a second layer;
A first detection step of reproducing data in any one of the first layer and the second layer and detecting whether or not a reproduction error or an error rate deteriorates;
A second detection step of detecting whether or not a reproduction error or a deterioration in error rate occurs at the same radius position of the other of the first layer and the second layer;
If a reproduction error or an error rate deterioration occurs in the second detection step, it is determined that the optical disc has a physical defect, and if it does not occur, the reproduction error or error rate detected in the first detection step is determined. A determination step for determining that the deterioration is caused by copy guard ;
An optical disc inspection method comprising:

Images