KR100998910B1 - Method and apparatus for determining an optimum laser power - Google Patents

Abstract

The present invention relates to a method and apparatus for determining an optimum power of a laser incident on a recording medium.

In order to achieve the above object, the present invention includes the steps of reading the position information of the first section for the optimum power test of the region for the optimal power test of the recording medium; Determining whether the first interval is defective; According to the determination result, it provides a method for determining the optimum power comprising the step of updating the address information of the area for the optimal power test.

Record carrier, optimum power, defect

Description

Method and apparatus for determining an optimum laser power

The present invention relates to a method and apparatus for determining an optimum power of a laser incident on a recording medium.

Discs such as DVD, BD, HD-DVD and the like are currently being developed / used as high capacity storage media. Such a disk uses a laser to recognize data of 0 and 1 for the difference in the amount of reflected light. Such discs can be broadly classified into read-only discs and recordable discs according to their functions and uses.

The data recording / reproducing apparatus for recording / reproducing data on the recordable disc records information on the optical disc by irradiating a laser beam of relatively large energy that can change the material properties of the recording layer provided on the recordable disc. The information is reproduced from the optical disc using a laser beam of small energy that does not change the material properties of the information recording layer. That is, during recording, information is normally recorded by driving the laser diode LD at a relatively high power to form pits on the optical disk.

Which laser power is used for recording is closely related to the recording quality and the reproduction quality for reproducing it. However, in order for the laser power to be optimal, it is related to the performance of the disc and the data recorder / player to be recorded and cannot be set as a uniform value. Therefore, the data recorder / player reproduces the optimum laser power and uses it for recording. A series of processes performed by the data recorder / player to find the optimal laser power is called power calibration or optimum power control (OPC).

The recordable disc has a test area to be used for the OPC, and the data recorder / player records the test signal in the test area, reproduces the recorded test signal and compares it with a predetermined reference value to determine the optimum laser power.

However, there is a problem that OPC is not performed properly due to defects in the test area and / or performance problems of the data recorder / player. If the OPC is not performed correctly, data cannot be recorded at the optimum laser power, and data cannot be recorded or an appropriate reproduction signal cannot be obtained even if recorded.

The present invention to solve the above problems, to provide a method and apparatus that can successfully perform OPC even if a defect exists in the test area.

In order to achieve the above object, the present invention includes the steps of reading the position information of the first section for the optimum power test of the region for the optimal power test of the recording medium; Determining whether the first interval is defective; According to the determination result, it provides a method for determining the optimum power comprising the step of updating the address information of the area for the optimal power test.

Reading the information of the position of the first section is characterized in that the reading from the management area of the recording medium.

The updating of the address information according to the determination result may include updating the start address information and / or the end address information of the region for the optimal power test if it is determined that the first section is defective.

The updating of the start address information and / or the end address information according to the determination result may include the start address information and / or the end address information so that the defect of the first section is not included in the region for the optimal power test. Characterized in that for updating.

According to the determination result, the updating of the start address information and / or the end address information is determined according to the position of the defective area.

According to the determination result, updating the start address information and / or the end address information may include starting address information so as to include a larger area of the divided areas when the area for the optimal power test is divided based on a defect. And / or update the end address information.

The optimal power region defined by the updated start address information and / or end address information may be greater than or equal to a predetermined unit size.

The unit size is characterized in that the minimum size required for the optimal power test.

The updated address information of the area for the optimal power test is recorded in the management area of the recording medium.

The updated address information of the area for the optimal power test is recorded in the management area in the form of start address information and end address information of the area.

In addition, the present invention and the pickup; In the region for the optimal power test of the recording medium, the position information of the first section for the optimal power test is read out, the defect is determined in the first section, and the region for the optimal power test according to the determination result. It provides an optimum power determination device comprising a control unit for updating the address information of the.

The updating of the address information according to the determination result may include updating the start address information and / or the end address information of the region for the optimal power test if it is determined that the first section is defective. It is done.

The updating of the start address information and / or the end address information according to the determination result may include the start address information and / or the end address information so that the defect of the first section is not included in the region for the optimal power test. It characterized in that to update.

According to the determination result, updating the start address information and / or the end address information includes a larger area of the divided areas when the area for the optimal power test is divided based on a defect. It is characterized by updating the start address information and / or end address information so as not to include.

The optimal power region defined by the updated start address information and / or end address information may be greater than or equal to a predetermined unit size.

The unit size is characterized in that the minimum size required for the optimal power test.

The present invention also provides a method for performing an optimum power test in a region allocated for performing an optimum power in an area for an optimal power test of a recording medium; Detecting a defect in the first section; And recording the position information of the second section for re-executing the optimum power test using the position information of the first section in which the defect is detected.

The recording of the location information of the second section by using the location information of the first section may include recording an end address of the first section.

The second section is characterized by starting from the next unit after the first section ends.

The recording of the position information of the second section is characterized in that the start position of the second section is the next unit of the end position of the first section.

The first section and the second section has a constant section length.

In addition, the present invention and the pickup; In the region for the optimal power test of the recording medium, the optimum power test is performed in the first interval allocated to perform the optimum power, the defect is detected in the first interval, and the position of the first interval in which the defect is detected. And a control unit for recording position information of a second section for re-executing the optimum power test using the information.

According to the present invention, even if a defect exists in the test area in the recording medium, OPC can be performed, thereby reducing errors in recording / reproducing of the recording medium.

In addition, even if a defect exists in the test area, it is possible to calculate an effective optimum laser power.

In addition, even if there is a defect in the test area, the optimum laser power can be calculated, so that stable recording medium can be recorded.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. In the following description, the same components are given the same names and the same reference numerals for the convenience of description.

The terminology used in the present invention was selected as a general term that is widely used at present, but in some cases, the term is arbitrarily selected by the applicant, and in this case, the meaning of the term is described in detail in the description of the present invention. It is to be understood that the present invention is to be understood as a meaning of terms other than the above.

1 shows an example of the overall configuration of a data recorder / player of the present invention.

The "data recorder / player" of the present invention is a device capable of recording or reproducing discs of various standards. Depending on the design, only a disc of a specific standard (for example, DVD, BD or HD-DVD) can be recorded / played back. It is also possible to play the data without recording. It is well known that the "data recorder / player" of the present invention can be a "drive" that can be embedded in a computer or the like. In addition to the function of recording / reproducing the disc 30, the data recording / reproducing apparatus of the present invention has a function of receiving an external input signal, processing the signal, and transmitting the signal to a user through another external display. In this case, there is no particular limitation on the inputtable external signal, but digital multimedia broadcasting and the Internet will be representative external input signals. In particular, the Internet is a medium that anyone can easily access at present, and can download and utilize specific data on the Internet through a data recorder / player. In this regard, it is also possible for the data recorder / player of the present invention to record the external input signal to the disc 30.

Looking specifically at the overall configuration of the data recorder / player, the data recorder / player first pick-up (11) for reproducing the management information, such as the original data and playback management file information recorded on the disc 30 and the Servo 14 that controls the operation of the pickup 11 and a focus error signal, which is a signal that detects the out-of-focus and the track-off of the laser beam by using the electrical signal output from the pickup 11. A digital signal received from the R / F unit 21 and a R / F unit 21 for generating a digital RF signal by generating a tracking error signal, shaping the electrical signal to a predetermined reference slice level, and outputting a digital RF signal. A signal processor 13 for restoring an RF signal to a desired reproduction signal value or modulating and transmitting a signal to be recorded into a signal recorded on a disk, and recording / rewriting of the disk. The memory 15 storing various necessary information necessary for the operation, the operation of the pickup 11, the signal processor 13, the servo 14, the memory 15 and the R / F unit 21 And a microcomputer 16 for controlling.

The pickup 11, the servo 14, the signal processor 13, the memory 15, the microcomputer 16, and the R / F unit 21 are also referred to as recording / reproducing units. In view of reproduction, the recording / reproducing section reads data from the disc 30 or the storage 19 under the control of the controller 12 and provides it to the decoder. In other words, the recording / reproducing section serves as a reproducing section (or reader section) for reading data from the viewpoint of reproduction. On the other hand, from a recording point of view, the recording / reproducing section is a recording section which receives a signal encoded by the AV encoder 18 and records video, audio data and the like on the disc 30.

In addition, the controller 12 (or host) is responsible for the control of all the components in the data recorder / player, and forms an interface with the user to control the reproduction of the recording medium, and to the outside of the recording medium by a user command or the like. The download of existing data is controlled. Specifically, the controller 12 transmits a command for performing a specific function to the recording / reproducing unit through the interface unit 20, and the microcomputer 16 in the recording / reproducing unit according to the command. The components in the recording / reproducing section are controlled.

In this regard, the controller 12 and the microcomputer 16 may be provided separately to operate. In addition, the functions of the controller 12 and the microcomputer 16 may be integrated to operate as one control unit. The controller may be composed of a program (software) and / or hardware provided in the data recorder / player.

In addition, the controller 12 and / or the microcomputer 16 may perform the following functions with regard to calculating the optimum power of the recording medium. If a defect is found in some sections of the region for optimal power in the recording medium, the section found to be defective or the section containing the defect is not suitable for the optimum power test. In this case, the controller 12 or the microcomputer 16 may update the address information of the region for the optimal power test to exclude the defect or the region where the defect occurs.

In addition, the AV decoder 17 finally decodes the data provided from the recording medium and / or the storage 19 into output data and provides the same to the user under the control of the controller. The AV decoder 17 may be configured of a plurality of decoders according to the type of data.

In addition, the AV encoder 18 converts an input signal into a signal of a specific format that can be recorded on the disk, for example, an MPEG-2 transport stream, under the control of a control unit to perform a function of recording a signal on the disk. It is provided to (13).

2 shows an example of the structure of a recordable recording medium having a test area. In the example of FIG. 2, a DVD is described as an example, but the spirit of the present invention is not limited to the DVD.

The recordable recording medium includes an information area and an R-information area. The information area includes a lead-in, a data recordable area, and a lead-out.

Further, an R-information area is allocated to the innermost circumference of the recordable recording medium. The R-information area includes an area for performing a test of optimal power. The area for performing the optimal power test may be referred to as a power calibration area (PCA) area. The R-information area may also include a Recording Management Area (RMA) associated with the recording of the record carrier. Moreover, the recording management area includes an area for performing an optimum power test and information related to the optimum power test.

Here, as an example of the optimal power test, the following operation may be performed. When the microcomputer 16 of the data recorder / player receives a command from the controller 12 to record data on the recording medium, the laser diode (LD) power of the pickup 11 is picked up in the PCA region of the pickup 11. The size is adjusted and the pickup 11 is controlled to record a predetermined test signal in the PCA area. Then, the pickup 11 is controlled so that a Beta Ratio value indicating an asymmetry ratio of the RF signal read and detected by the recorded test signal is recorded to be close to zero. It automatically performs a series of OPC operations to adjust the recording power value.

The OPC operation as described above is performed by a test block having a predetermined size (for example, 1 error correction code (ECC) unit, 1 cluster unit, sector). Alternatively, a plurality of blocks may be used for one OPC. As an example, 16 sectors or 16 ECCs may be used during one OPC. The type and predetermined size of the block may vary depending on the performance of the standard and data recorder / player.

Whenever a new OPC operation is required, the microcomputer 16 repeatedly performs a series of OPC operations each time in order to normally record data on the recording medium. In this case, the microcomputer 16 may use the test blocks in the PCA region in a predetermined order, for example, in the reverse or the reverse direction of the track direction. Of course, depending on the type of recording medium or the implementation of the recorder / player, the test blocks in the PCA area may be randomly used. Hereinafter, for convenience of description, the case where the test units in the recording medium are used in the reverse order of the track direction of the recording medium will be described as an example.

The data recorder / player can use the recording management data recorded on the recording medium to determine the test unit to be used for the OPC. The recording management data is recorded in a management area, for example, a recording management area (RMA) area, allocated to a predetermined position of the recording medium. The microcomputer 16 controls the pickup 11 to read recording management data from the RMA area, and uses the read recording management data in the data recording / reproducing process.

FIG. 3 shows an example of recording management data recorded in a management area of a recording medium, wherein information relating to OPC, for example, recording power obtained by OPC, and time and date at which OPC was performed, are shown. A time stamp, a power calibration address specifying a test block on which the last power calibration was performed, and the like can be recorded in the RMD area as the recording management data.

In this regard, the power calibration address may specify the next available test block instead of specifying the test block on which the last power detection was performed. However, hereinafter, for convenience of description, the case where the power detection address is location information specifying the test block on which the last power detection is performed will be described as an example.

FIG. 4 is a diagram for one embodiment of a method of performing optimal power when a defect occurs during a process of performing optimal power in a PCA region allocated to a power test.

In general, when the controller 12 transmits a recording command to the recording / reproducing section, the recording / reproducing section uses some space of the memory 15 as a buffer to perform buffering in real time. Depending on the size of the buffer, the time required for OPC operation is limited. That is, if the OPC continues after a certain time limit, the microcomputer 16 determines that the OPC has failed. Therefore, when OPC is performed in a section including a defect, OPC may fail due to a time delay. In addition, when the OPC is not properly performed, there is no information on the area where the OPC can be re-executed, which may cause problems in the re-execution of the OPC.

4 allocates a plurality of sectors for OPC. Also, for convenience of description, an example in which the first OPC is performed on the recordable recording medium is shown. For the first OPC, 16 sectors of the record carrier were allocated at the very beginning in the direction in which the OPC performed. In this case, the 16 allocated sectors may be referred to as a first interval. In addition, the following description of the OPC area will be described based on the direction in which the OPC proceeds.

4 shows a case where a defect occurs in the sixteenth sector among the sectors in the first section. In addition, although a case where a defect occurs in the 16th sector is shown for convenience of description, it is obvious that the present invention can be applied to a case where a defect occurs in any one of the 16 sectors in the first section.

The defect in the first section does not allow the OPC performed in the first section to terminate normally. At this time, it is preferable to record the value in a management area such as a recording management area (RMA) for a section in which normal termination has not been completed. At this time, the position information of the first section in which the defect occurs can be recorded. Alternatively, the start position information of the second section for performing the OPC may be recorded.

When the position information of the first section is recorded in the recording management area, the start position information of the second section for re-executing the OPC may include the next sector or ECC of the end position of the first section for efficient use of the recording management area. It may be a block. When the position information of the second section is recorded in the recording management area, the position information of the second section may be recorded as a sector or ECC block following the end of the first section.

In addition, as described above, the OPC may be performed for a section having a predetermined size, and thus, if there is a start address information of the second section or end position information of the first section, the OPC may be re-executed in the second section.

Figure 5 shows a flow chart of a first embodiment according to the present invention. The OPC is performed in the section allocated for the OPC (S10). The interval allocated for the OPC is a portion of the PCA region as shown in FIG. 4. Defects are detected during the performance of the OPC (S20). As described above, one of the sections allocated for the OPC may be referred to as a first section in which a defect has occurred. When a defect occurs in the first section, the performing OPC may be stopped, or the microcomputer 16 or the controller 12 may be called. Control allows you to issue an OPC interrupt.

If the OPC is not normally terminated due to a defect in the first section, the location information of the second section for re-execution of the OPC is recorded (s40). The position information of the second section may be recorded by recording the start position information of the second section or by recording the end position information of the first section. The location information of the second section may be recorded in the recording management area RMA.

In addition, when no defect occurs in the first section, OPC may be performed and OPC may be normally terminated. When the OPC ends normally, the end position information of the normally terminated first section is recorded in the recording management area RMA. Alternatively, as in the case of abnormal termination, the start position information of the second section may be recorded in the recording management area.

Here, the start position information of the second section or the end position information of the first section recorded when the normal section ends abnormally and the abnormal section ends may be recorded in another field.

6 shows a second embodiment according to the invention. The present invention relates to a method of changing address information of a PCA area when a defect is allocated in a first section allocated in the PCA area, which is an area for an optimal power test. In particular, an embodiment of a method of changing start position information such as a PCA area is shown.

For example, in the embodiment of FIG. 6, the first section is allocated to the foremost part of the PCA region (based on the power calibration direction) as in the embodiment of FIG. 4. This is for convenience of description.

As shown in FIG. 6, when a defect occurs in one sector of the first section, start address information of the PCA area may be changed. The start address information (1) of the original PCA region may update the next ECC block or sector of the ECC block or sector where the first section ends to the start address (②) information of the PCA region.

At this time, the PCA area defined by the updated address information does not include the defect of the first section. In addition, in updating the address information of the PCA area, the address information may be updated based on a predetermined unit size. That is, instead of updating the next sector or ECC block of the defective position with the start position information of the PCA region, the next sector or ECC block of the position where the first section including the defect ends may be updated. Herein, the unit size means a minimum size for performing the OPC area, which may vary depending on a standard and a recording / reproducing apparatus of a recording medium. For example, in the case of a DVD-RW, 16 sectors or one ECC block may be used as a basic unit for OPC.

In addition, the updated address information may be recorded in the form of a table in the recording management area (RMA). In a recordable recording medium, address information such as a PCA area may be embossed on the recording medium. In such a case, since the original address information cannot be deleted and recorded again, it is preferable that the original address information is recorded in the form of a table or the like on the recording management area RMA. Alternatively, the address information of the current PCA area in the RMA area may be updated each time OPC is performed, apart from the address information imposed.

7 shows a third embodiment according to the invention. FIG. 7 relates to a method of changing address information of a PCA area when there is a defect in a first section allocated in the PCA area which is an area for an optimal power test according to the present invention. In particular, an embodiment of a method of changing the end position information such as the PCA area is shown.

In the embodiment of FIG. 7, the first section is allocated at the rear end of the PCA region. Also, a case where a defect occurs in block 7087 in the first section.

When a defect occurs in the first section, the end position information of the PCA area may be updated. At this time, the original PCA area end position is the end position (③) of sector 7088, but the end position information of the changed first section (4) becomes the address information of sector 7072. In the updating and recording method for the address information of the PCA area, the rules described in the above-described embodiment of FIG. 6 may be applied.

8 is a flowchart illustrating an optimal power test method according to the present invention. 8 illustrates an optimal power test method in performing the second embodiment or the third embodiment.

First, the position information of the section to perform the OPC is read (S110). The section to perform OPC is included in the PCA region. In addition, the interval for performing OPC has a certain unit length, the unit length may be defined by a plurality of sectors or at least one ECC block. In addition, for convenience, the section in which the OPC is to be performed is named as the first section as described above.

The first section, that is, whether or not the defect of the OPC execution section is checked (S120). By checking whether the defect is present or not (S130), OPC may be performed by resetting or maintaining the address information of the PCA area. If a defect occurs in the OPC area, the PCA start address information or end address information may be changed (S140).

At this time, whether to change the PCA start address or the PCA end address of the PCA area depends on the position of the defect or the position of the section including the defect. Can be determined. For example, when a defect occurs in front of the PCA region as shown in FIG. 6, the PCA region may be reset by changing the start address information of the PCA region. In addition, in the embodiment illustrated in FIG. 7, since a defect occurs behind the PCA area, the PCA area may be reset by updating the end address information of the PCA area. 6 and 7, the PCA area defined by the updated address information is larger than the abandoned PCA area.

If the PCA area is reset by updating the address information of the PCA area, the OPC is re-executed in the reset PCA area (S150). In this case, the above-described steps may be repeated by setting a section having the same unit length as the first section for performing OPC again in the reset PCA region. In this case, the reset section may be referred to as a second section for convenience.

If a defect is not found in the first section, the OPC is performed in the first section (S160).

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

1 shows an example of the overall configuration of a data recorder / player of the present invention.

2 shows an example of the structure of a recordable recording medium having a test area.

3 shows an example of recording management data recorded in a management area of a recording medium.

4 and 5 are diagrams for explaining the first embodiment of the present invention.

6 is a diagram for explaining a second embodiment of the present invention.

7 is a diagram for explaining a third embodiment of the present invention.

8 is a diagram for explaining a second embodiment and a third embodiment of the present invention.

Claims (22)

Reading position information of a first section for performing the optimum power test, from an area for an optimal power test of a recording medium; Determining whether the first interval is defective; If a defect occurs in the first section, updating the start address and / or the end address of the region for the optimal power test so as not to include the defect region in the first section, In the updating of the start address and / or the end address, when the region for the optimal power test is divided based on the first interval, the region for the optimal power test includes a larger region among the divided regions. Optimal power determination method, characterized by updating the start address and / or end address. The method of claim 1, And reading the position information of the first section comprises reading from recording management data recorded in a management area of the recording medium. delete delete delete delete The method of claim 1, And a region for the optimum power test defined by the updated start address and / or end address is greater than or equal to a predetermined unit size. The method of claim 7, wherein Wherein the unit size is a minimum size necessary for the optimum power test. The method of claim 1, The updated start address and / or end address of the area for the optimum power test is recorded in the management area of the recording medium. delete A pickup unit for recording or reading data on a recording medium; Controlling the pickup unit to read the position information of the first section for performing the optimum power test in the region for the optimal power test of the recording medium, It is determined whether the first section is defective, And a controller for updating a start address and / or an end address of an area for the optimal power test so as not to include a defective area of the first section when a defect occurs in the first section. When the area for the optimal power test is divided based on the first interval, the controller may select the start address and / or the end address to include a larger area among the divided areas for the optimal power test. The optimum power determination device, characterized in that for updating. The method of claim 11, And the control unit controls the pickup unit to read the position information of the first section from the recording management data recorded in the management area of the recording medium. The method of claim 11, And the control unit controls the pickup unit to record the updated start address and / or end address of the area for the optimal power test in the management area of the recording medium. delete The method of claim 11, And an area for the optimum power test defined by the updated start address and / or end address is equal to or greater than a predetermined unit size. The method of claim 15, And the unit size is a minimum size necessary for the optimum power test. delete delete delete delete delete delete

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