JP2007213646A - Optical disk recording/reproducing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical disk recording/reproducing apparatus which can perceive occurrence of physical destruction of a rewritable optical disk in advance. <P>SOLUTION: When the loaded optical disk concerned is determined as a rewritable optical disk and when writing of information is performed to the optical disk concerned, a jitter of an RF signal which is a reading signal from an existing recording area of the optical disk concerned is detected and a rate of occurrence of a block error in a digital signal processing section is also detected. With reference to the jitter or/and the rate of occurrence of block error detected above, a recording property by temporal change of the optical disk concerned is checked. When the recording property is determined being over a reference value, a message which warns a user that the optical disk concerned has possibility of being destroyed is displayed on a display device. The user understands that the optical disk concerned is not rewritable any more by such a message. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical disc recording / reproducing apparatus for recording / reproducing information on / from an optical disc, and more particularly, to a process for examining the quality of an optical disc.

  In recent years, DVDs (digital versatile discs), which are optical discs capable of recording information such as a large amount of video and audio data such as movies, are becoming widespread. As types of DVDs, a DVD-ROM in which information is recorded on the manufacturer side and cannot be rewritten on the user side, a DVD-R or DVD + R on which information can be recorded only once on the user side, and a DVD- that can be rewritten a specified number of times on the user side. RW, DVD + RW, DVD-RAM, etc. are known. Information recorded on these DVDs can be reproduced by an optical disk reproducing device (DVD player) or an optical disk recording / reproducing device (DVD recorder), and information to DVD-R, DVD + R, DVD-RW, DVD + RW, DVD-RAM. This recording can be performed by an optical disk recording / reproducing apparatus (DVD recorder).

By the way, in a rewritable optical disc such as DVD-RW, DVD + RW, or DVD-RAM, when information is repeatedly rewritten, the remaining components increase due to various causes such as characteristic deterioration of the medium material itself and tracking deviation, resulting in recording quality. Will be reduced. In a rewritable optical disk, a phase change recording method using a change in state between an amorphous state and a crystal is adopted. Therefore, the number of times of rewriting is clearly limited due to deterioration of recording characteristics of the material itself. If the rewrite operation is performed without knowing that the limit of the number of rewrites has been exceeded or close to the limit, the recording quality deteriorates due to a significant decrease in the S / N ratio of the sector or an increase in crosstalk to adjacent tracks. cause.
JP 2005-158140 A JP-A-7-130106 JP-A-7-130107 Japanese Patent Laid-Open No. 11-167773 JP-A-2-230563

  A rewritable optical disk is formed by DOW (Direct Over Write) (overwriting by direct laser beam irradiation) when repetitive recording is performed, and a DVD + RW, DVD-RW, or DVD-RAM optical disk is a standard. The upper 1000 times of DOW is guaranteed, but if the rewrite operation is performed without knowing that the limit of the number of rewrites has been exceeded or close to the limit, the SN ratio of the sector is significantly lowered or the adjacent track is moved to. Due to the increase in crosstalk, the recording quality is not only lowered, but the optical disk may be physically destroyed before reaching 1000 times depending on the recording situation. The cause of the physical destruction is due to the disk structure, the disk material, the power of the laser beam during recording, and the like. In particular, when the power of the laser beam at the time of recording is increased, the optical disk is quickly destroyed.

  However, in the conventional optical disc recording / reproducing apparatus, such a rewritable optical disc is loaded and information is recorded on the optical disc. However, since the information is recorded on the optical disc as digital information, the optical disc is physically There is a problem in that the playback video is not deteriorated until just before the destruction, and it is difficult for the user to determine the disk state.

  In the prior art of Patent Document 1, a pickup (optical pickup) reads a disk (optical disk) to generate a reproduction signal, and the reproduction signal is amplified by a read amplifier (RF amplifier). Then, the quality state of the disk is measured from the amplified reproduction signal and the control state from the servo control unit to obtain a measurement result. The controller compares the measurement result with a predetermined threshold value for each quality, and if the measurement result exceeds the threshold value, displays that fact on the display unit, so that the quality of the disc with respect to the playback device can be determined by the user. This makes it possible to make simple judgments.

  However, this prior art makes it possible to judge the quality of the disc during reproduction, but does not disclose a specific configuration for measuring the result of the quality of the disc during recording and displaying it on the display unit. Therefore, this prior art cannot cope with a case where a rewritable optical disc is loaded and the optical disc causes physical destruction at the time of recording information on the optical disc. The reproduced video is not deteriorated, and therefore the problem that it is difficult for the user to determine the disc state cannot be solved.

  In the prior art of Patent Document 2, the reproduction error rate is written in the test area by the recording means, the reproduction error rate management means for reading the reproduction error rate written in the test area by the reproduction means, and the reproduction error before and after the recording / reproduction test. By providing a recording / reproduction control means for reporting an abnormality based on the difference in rate or changing the recording circuit parameter and the reproduction circuit parameter, it is possible to determine whether the cause of the abnormality related to the increase in the reproduction error rate is an apparatus or a medium. If the medium is a rewritable optical disc, the recording characteristics deteriorate as the number of rewrites increases, and the optical disc may cause physical destruction during recording. Because it is not possible to cope with it, the playback video is displayed until immediately before the optical disk is physically destroyed. It does not occur, such as deterioration, can not solve the problem that is difficult to determine the disk state in this order the user side.

  In the prior art of Patent Document 3, when inspecting the quality of a disc on which a digital signal is recorded in units of blocks to which an error detection / correction code is assigned, the optical axis is tilted at a predetermined angle with respect to the disc to be rotated. The digital signal recorded on the disk is reproduced by irradiating the laser beam, the reproduced digital signal is demodulated, an error is detected using an error detection correction code, and the number of errors per unit time is integrated. The quality of the disk is determined based on the integration result.

  However, this prior art makes it possible to easily and reliably discriminate a disc with a small disc warp margin among the produced high-density recording discs. Since it cannot be dealt with when the optical disk causes physical destruction during recording of information on this optical disk, there is no deterioration in the playback video until just before the optical disk causes physical destruction, For this reason, the problem that it is difficult for the user to determine the disk state cannot be solved.

  The prior art of Patent Document 4 detects the jitter amount of the data signal read from the optical disk, compares it with a predetermined threshold value, and if it exceeds the predetermined threshold value, notifies the upper CPU that the recording medium is fatigued, and creates a new sector. By recording data on the optical disc, the recordable area of the optical disc is used without waste.

  However, in this conventional technique, if the optical disk is fatigued, data is recorded in a new sector of the optical disk. However, the sector on which data has already been recorded is overwritten and rewritten many times. However, there is no disclosure of measures against physical destruction, so there is no degradation in the playback video until immediately before the optical disk is physically destroyed, so the user must determine the disk status. Cannot solve the above-mentioned problem of being difficult.

  In the prior art of Patent Document 5, the degree of deterioration of the disk is determined by comparing the error rate obtained by CD reproduction with the past error rate, and the determination result is reported on the display unit. The optical discs handled in the above are read-only CDs, and are not related to processing on rewritable optical discs.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical disc recording / reproducing apparatus capable of detecting in advance before physical destruction of a rewritable optical disc occurs. And

  In order to achieve the above object, according to the first aspect of the present invention, it is determined that the loaded optical disc is a rewritable optical disc, the writing of information to the optical disc is started, and the writing of information is executed by the optical pickup. Jitter detection means for detecting jitter of an RF signal that is an output signal of an optical pickup that has read information from the recorded area of the optical disc, and after converting the RF signal into digital data, Block error occurrence rate detecting means for detecting a block error occurrence rate in a digital signal processing unit for performing signal demodulation processing and error correction processing, and referring to the detected jitter or / and block error occurrence rate, Recording characteristic confirmation means for confirming recording characteristics due to change over time, Recording characteristic determination means for determining whether or not the confirmed recording characteristic exceeds a predetermined reference value, and when it is determined that the confirmed recording characteristic exceeds a predetermined reference value, the optical disc There is provided an optical disc recording / reproducing apparatus comprising a system controller having a message output means for causing a display means and / or an audio output means to output a message warning that there is a fear of being destroyed.

  In this configuration, it is determined that the loaded optical disc is a rewritable optical disc, and writing of information to the optical disc is executed by the optical pickup. At this time, information on the recorded area of the optical disc is read by the optical pickup. Read out. The jitter detection means detects the jitter of the RF signal that is the read signal from the optical pickup that has read the information of the recorded area of the optical disc, and the block error occurrence rate detection means generates a block error in the digital signal processing unit. Detect rate.

  Next, the recording characteristic confirming means confirms the recording characteristic due to the time change of the optical disc with reference to the detected jitter or / and block error occurrence rate. Thereafter, the recording characteristic determining means determines whether or not the confirmed recording characteristic exceeds a predetermined reference value. If it is determined that the recording characteristic due to the time change of the jitter exceeds the reference value or / and the recording characteristic due to the time change of the block error occurrence rate exceeds the reference value, the message output means Displays a message, for example, on the display device, warning the user that there is a risk of being destroyed. The display of such a message indicates that the user cannot rewrite the optical disc any more.

  In a rewritable optical disk such as DVD-RW, DVD + RW, or DVD-RAM, repetitive recording is possible. However, the recording power of the laser beam emitted from the optical pickup is too high, or repetitive recording is performed. As a result, the state of the optical disk deteriorates, and eventually the optical disk causes physical destruction, and recording / playback cannot be performed, but according to this configuration, before the physical destruction occurs on the optical disk, It is possible to detect the state of the optical disc in advance and prevent loss of valuable information during recording.

  According to the second aspect of the present invention, when it is determined that the loaded optical disk is a rewritable optical disk, the writing of information to the optical disk is started and the writing of information is executed by the optical pickup. A digital signal for detecting jitter of an RF signal that is an output signal of an optical pickup that reads information from a region, and performing signal demodulation processing and error correction processing according to the data format of the optical disc after converting the RF signal into digital data A processing unit detects a block error occurrence rate, refers to the detected jitter or / and block error occurrence rate, confirms the recording characteristics of the optical disc over time, and the confirmed recording characteristics are determined in advance. If it is determined that the specified reference value has been exceeded, the optical disc is destroyed. The fear to provide an optical disc recording and reproducing apparatus characterized by comprising a system controller to be output to the display means and / or the audio output unit a message to warn that there is.

  In this configuration, it is determined that the loaded optical disc is a rewritable optical disc, and writing of information to the optical disc is executed by the optical pickup. At this time, information on the recorded area of the optical disc is read by the optical pickup. Read out. Then, jitter of the RF signal that is a read signal from the optical pickup that has read the information of the recorded area of the optical disc is detected, and the block error occurrence rate in the digital signal processing unit is detected.

  Next, with reference to the detected jitter or / and block error occurrence rate, the recording characteristics of the optical disc with time change are confirmed. Thereafter, if it is determined that the recording characteristic due to the time change of the jitter exceeds the reference value, and / or the recording characteristic due to the time change of the block error occurrence rate exceeds the reference value, the optical disk is destroyed. For example, a message that warns the user that there is an error is displayed on the display device. The display of such a message indicates that the user cannot rewrite the optical disc any more.

  In a rewritable optical disk such as DVD-RW, DVD + RW, or DVD-RAM, repetitive recording is possible. However, the recording power of the laser beam emitted from the optical pickup is too high, or repetitive recording is performed. As a result, the state of the optical disk deteriorates and eventually the optical disk causes physical destruction, and recording / playback cannot be performed. However, according to this configuration, before the physical destruction of the optical disk occurs, It is possible to detect the state in advance and prevent loss of valuable information during recording.

  According to a third aspect of the present invention, in the second aspect of the invention, the system controller determines that the loaded optical disk is a rewritable optical disk, and writing of information to the optical disk is started so that writing of information is performed by the optical pickup. And a jitter detection means for detecting jitter of an RF signal that is an output signal of an optical pickup that has read information from a recorded area of the optical disc, and after converting the RF signal into digital data, A block error occurrence rate detecting means for detecting a block error occurrence rate in a digital signal processing unit that performs signal demodulation processing and error correction processing according to a data format, and the detected jitter or / and block error occurrence rate are referred to. Recording characteristics of the optical disc over time A recording characteristic confirmation unit for recognizing, a recording characteristic determination unit for determining whether or not the confirmed recording characteristic exceeds a predetermined reference value, and a determination that the confirmed recording characteristic exceeds a predetermined reference value In this case, the optical disc has a message output means for causing the display means and / or the audio output means to output a message warning that the optical disc may be destroyed.

  Therefore, the system controller can realize a jitter detection process, a block error occurrence rate detection process, a recording characteristic confirmation process, a recording characteristic determination process, and a message output process, so that before physical destruction occurs in the optical disc, Processing for outputting a warning message can be performed.

  As described above, according to the present invention, when it is determined that the loaded optical disc is a rewritable optical disc, and writing of information to the optical disc is started and writing of information is executed by the optical pickup, the optical disc Jitter detecting means for detecting jitter of an RF signal that is an output signal of an optical pickup that has read information from the recorded area, and signal demodulation processing corresponding to the data format of the optical disc after the RF signal is converted into digital data Block error occurrence rate detecting means for detecting a block error occurrence rate in a digital signal processing unit that performs error correction processing, and recording characteristics of the optical disc by time change with reference to the detected jitter or / and block error occurrence rate Recording characteristic confirmation means for confirming the recording and the confirmed recording Recording characteristic determining means for determining whether or not the characteristic exceeds a predetermined reference value, and when it is determined that the confirmed recording characteristic exceeds a predetermined reference value, the optical disc may be destroyed. A system controller having a message output means for outputting a warning message to the display means and / or the audio output means, so that the state of the optical disk is detected in advance before the optical disk is physically destroyed. It is possible to prevent loss of valuable information during recording.

  Further, according to the present invention, when it is determined that the loaded optical disc is a rewritable optical disc, and writing of information to the optical disc is started and information writing is being executed by the optical pickup, Digital that performs jitter detection of an RF signal that is an output signal of an optical pickup that reads information from a recording area, and performs signal demodulation processing and error correction processing according to the data format of the optical disc after the RF signal is converted into digital data A block error occurrence rate is detected in the signal processing unit, and a recording characteristic due to a time change of the optical disc is confirmed with reference to the detected jitter or / and block error occurrence rate. If it is determined that the specified reference value has been exceeded, the optical disc Since the system controller for outputting a message warning that there is a fear of being broken to the display means and / or the audio output means is provided, the state of the optical disk can be detected in advance before the optical disk is physically destroyed. It is possible to prevent loss of valuable information during recording.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram showing a configuration of an optical disc recording / reproducing apparatus according to an embodiment of the present invention.

  The optical disk recording / reproducing apparatus includes a system controller 22 that controls the entire apparatus, a spindle motor 5 that rotates the optical disk 1, an optical pickup 2 that optically writes / reads information to / from the optical disk 1, and the optical pickup. The spindle motor 5 and the sled 3 are driven through the motor driving circuit 34 according to the instruction of the system controller 22 and the sled 3 for moving the optical disc 2 in the radial direction of the optical disc 1 and the objective incorporated in the optical pickup 2 And a servo control unit 4 that performs control to move the focal position of the laser light in the vertical direction and the horizontal direction with respect to the recording surface of the optical disc 1 by moving a lens (not shown).

  The optical disc recording / reproducing apparatus also amplifies an RF signal which is a read signal from the optical pickup 2 during reproduction of the optical disc 1 and converts the RF signal output from the RF amplifier 6 into digital data. A digital signal processing unit 8 that stores data generated by performing signal demodulation processing and error correction processing according to the data format of the optical disc 1 in a RAM 7 as a buffer memory, and a digital signal processing unit 8 according to an instruction from the system controller 22 Is provided with a stream separation unit 9 that separates audio data, sub-picture data, and video data from the data stream output from.

  The optical disc recording / reproducing apparatus also receives an audio decoder 11 that receives the audio data output from the stream separation unit 9 and performs a predetermined decoding process, and temporarily stores the data to perform the decoding process in the audio decoder 11. The RAM 10 to be stored in the sub-picture decoder 13, the sub-picture decoder 13 that inputs the sub-picture data output from the stream separation unit 9 and performs a predetermined decoding process, and the sub-picture decoder 13 temporarily stores the data to perform the decoding process. A video MPEG decoder 15 that receives the video data output from the stream separation unit 9 and decodes it in MPEG, and temporarily stores the data for decoding in the video MPEG decoder 15. RAM 14 for storing.

  The optical disk recording / reproducing apparatus also includes a video processor 17 that synthesizes the data output from the video MPEG decoder 15 and the data output from the sub-picture decoder 13 in accordance with an instruction from the system controller 22, and the video processor 17. A video encoder 18 that converts the output synthesized data into a video signal for display and displays an image on the display device 20, and an audio circuit (not shown) that converts the data output from the audio decoder 11 into an analog audio signal. For example, a D / A converter 16 supplied to the speaker 19 is provided.

  The optical disc recording / reproducing apparatus also performs various operations such as a recording key for giving a recording instruction to the system controller 22, a reproducing key for giving a reproducing instruction, and a stop key for giving a recording / reproducing stop instruction. A remote controller 21 having keys and a main body operation unit (not shown) having fewer operation keys than the operation keys of the remote controller 21 are provided. The optical disc recording / reproducing apparatus also includes a flash ROM 23 as a nonvolatile memory storing programs and data for controlling each component of the apparatus and controlling the entire apparatus, and a program for the flash ROM 23. A CPU 24 that performs arithmetic processing according to the data and controls the system controller 22 and a RAM 27 that temporarily stores data necessary for the arithmetic processing of the CPU 24 are provided.

  The optical disk recording / reproducing apparatus also includes a tuner 29 connected to an antenna 28, an analog video / audio signal of a television broadcast selected by the tuner 29, or a television receiver or other video / audio output not shown. An A / D conversion circuit 30 that converts a video / audio signal from the device into digital video / audio data, an MPEG encoder 31 that encodes the video / audio data in MPEG, and the encoded video / audio data (encoded data) temporarily. In order to record the encoded data sent from the ATAPI 33 on the optical disc 1, the RAM 32 as a buffer memory that stores a predetermined amount in the memory, the ATAPI (AT Attachment Packet Interface) 33 that is an interface connected to the recording data modulation circuit 25, and the like. Recording data change that modulates A circuit 25; and a laser modulation circuit 26 that outputs a laser modulation signal for modulating the laser beam emitted from the optical pickup 2 to the optical pickup 2 based on the modulation data modulated by the recording data modulation circuit 25. Yes.

  The system controller 22 determines that the loaded optical disk is a rewritable optical disk as a characteristic element of the present embodiment, starts writing information on the optical disk, and writes the information by the optical pickup. A jitter detection means 221 for detecting jitter of an RF signal that is an output signal of an optical pickup that has read information from an already recorded area of the optical disc, and a data format of the optical disc after the RF signal is converted into digital data Block error occurrence rate detecting means 222 for detecting a block error occurrence rate in the digital signal processing unit 8 for performing signal demodulation processing and error correction processing according to the above, and referring to the detected jitter or / and block error occurrence rate. To record the time change of the optical disc A recording characteristic confirmation unit 223 for confirming characteristics, a recording characteristic determination unit 224 for determining whether or not the confirmed recording characteristic exceeds a predetermined reference value, and a reference value for which the confirmed recording characteristic is a predetermined value. And a message output means 225 for causing the display device 20 and / or the speaker 19 to output a message warning that the optical disc may be destroyed.

  FIG. 2 is an explanatory diagram showing an example of the relationship between the number of data rewrites and jitter on the rewritable optical disc in the present embodiment. In FIG. 2, L1 is a characteristic line showing the relationship between the number of rewrites in the optical disc and the jitter of the RF signal when the number of rewrites is guaranteed 1000 times according to the standard. According to this characteristic line L1, when the number of rewrites exceeds 1000, the jitter increases rapidly, indicating that the optical disc cannot be rewritten. In addition, L2 cannot be rewritten when the number of rewrites has not reached 1000 times and the jitter has exceeded the jitter reference value a at n times and the number of rewrites has exceeded n times. It is the characteristic line which shows. This characteristic line L2 is because the optical disk is physically destroyed before the number of rewrites reaches 1000. The factors that are physically destroyed are due to the disk structure, the disk material, the power of the recording laser beam, and the like. In particular, when the power of the recording laser beam is increased, the optical disk is quickly destroyed.

  FIG. 3 is an explanatory diagram showing an example of a temporal change in jitter detected when the number of data rewrites is n times for the rewritable optical disc in the present embodiment. In FIG. 3, L3 indicates the recording characteristic line of the optical disc with respect to the time change of jitter, and the recording characteristic indicated by the recording characteristic line L3 rapidly increases beyond the jitter reference value a at time t1. If the recording characteristic indicated by the recording characteristic line L3 exceeds the jitter reference value a, the optical disk may not be able to be recorded, or may cause physical destruction that is a disk state that cannot be reproduced even if recording is possible. I understand that there is.

  FIG. 4 is an explanatory diagram showing an example of a temporal change in BLER (block error occurrence rate) detected when the number of data rewrites is n times for the rewritable optical disc in the present embodiment. In FIG. 4, L4 is a recording characteristic line with respect to the BLER time change, and the recording characteristic indicated by this recording characteristic line L4 rapidly increases beyond the BLER reference value b at time t2. If the recording characteristic indicated by the recording characteristic line L4 exceeds the BLER reference value b, the optical disk may not be able to be recorded, or may cause physical destruction that is a disk state that cannot be reproduced even if it can be recorded. I understand that there is.

  FIG. 5 is a flowchart for explaining the process of detecting the disk status in this embodiment. Processing for detecting the disk state will be described with reference to this flowchart and FIGS.

  First, when the optical disk 1 is loaded, the system controller 22 detects the loading of the optical disk 1 (step S1), rotates the optical disk 1 a little and drives the optical pickup 2 to record disk information from the control data area of the optical disk 1. A so-called mounting process is performed (step S2), and it is determined from the disc information whether the optical disc 1 is a rewritable disc (rewritable optical disc) (step S3).

  If it is determined that the optical disc 1 is not a rewritable disc, this process ends. If it is determined that the optical disc 1 is a rewritable disc, the system controller 22 is pressed when the recording key of the remote controller 21 is pressed. Rotates the optical disk 1 by rotating the spindle motor 1 via the servo controller 4 and the motor drive circuit 34, and uses the optical pickup 2 as an object of the optical disk 1 via the servo controller 4 and the thread 3. While moving to a radial position and driving an actuator (not shown) via the servo control unit 4, the objective lens built in the optical pickup 2 is focused on the target position of the optical disk 1.

  If the information to be written on the optical disk 1 is, for example, a television program received by the antenna 28 and selected by the tuner 29, the video / audio signal from the tuner 29 is an A / D that performs the operation as described above. Processing is performed by the conversion circuit 30, MPEG encoder 31, RAM 32, ATAPI 33, recording data modulation circuit 25, and laser modulation circuit 26, and writing to the optical disc 1 is started via the optical pickup 2 (step S4). This writing process and the reading process described below are made possible by the system controller 22 performing a writing operation or a reading operation on the optical pickup 2 at predetermined time intervals.

  When writing is started by such processing, information is recorded on the optical disc 1, and thus there is a recorded area in which information is already recorded in the recording area of the optical disc 1. Therefore, the system controller 22 changes the optical pickup 2 from the writing operation to the reading operation, and when the optical pickup 2 reads information on the recorded area of the optical disc 1, the system controller 22 reads information on the recorded area. (Step S5), the jitter detection means 221 of the system controller 22 amplifies an RF signal that is a read signal from the optical pickup 2 that has read information on the recorded area of the optical disc 1. The RF signal that is the output signal of the RF amplifier 6 is input and the jitter of the RF signal is detected, and the block error occurrence rate detecting means 222 converts the RF signal that is the output signal of the RF amplifier 6 into digital data, and then the optical disc 1. Signal demodulation processing and error correction processing compatible with any data format Detecting the BLER (block error rate) of the digital signal processing unit 8 to perform (step S6).

  The detected jitter and BLER are stored in the reserved area in the lead-in of the optical disc 1, and then the recording characteristic confirmation means 223 of the system controller 22 refers to the jitter or / and BLER stored in the reserved area. Then, the recording characteristics of the optical disc 1 due to changes over time are confirmed (step S7).

  If the recording characteristic is due to the time change of the jitter, for example, the recording characteristic as shown by the line L3 in FIG. 3 is confirmed. If the recording characteristic is due to the time change of the BLER, the recording characteristic as shown by the line L4 in FIG. Confirm. By checking not only the jitter but also the BLER, it is possible to detect how much error correction has been performed on the recording data of the optical disc 1, and the disc state can be easily understood.

  Normally, before the disk is destroyed, the jitter and block error occurrence rate rapidly deteriorates due to the influence of the laser power, so the past jitter and block error occurrence rate data stored in the reserved area in the lead-in of the optical disc 1 is also in the disk state. It will be used as judgment material.

  Thereafter, the recording characteristic determination unit 224 of the system controller 22 determines whether or not the confirmed recording characteristic exceeds a predetermined reference value (step S8). That is, the recording characteristic determination unit 224 of the system controller 22 determines whether or not the recording characteristic due to the time change of jitter exceeds the reference value, and / or whether or not the recording characteristic due to the time change of BLER exceeds the reference value. . For example, as shown in FIG. 3, it is determined whether or not the line L3 indicating the recording characteristics due to the time change of jitter exceeds the reference value a at time t1, and as shown in FIG. It is determined whether or not the line L4 indicating the recording characteristics exceeds the reference value b at time t2.

  It was determined that the recording characteristics (line L3 in FIG. 3) due to the time change of jitter did not exceed the reference value a, and the recording characteristics (line L4 in FIG. 4) due to the time change of BLER did not exceed the reference value b. In this case, the processing from step S5 to step S9 is repeated until the normal recording operation is completed, but if the recording characteristics (line L3 in FIG. 3) due to the time change of jitter exceeds the reference value a, or / and When it is determined that the recording characteristic (line L4 in FIG. 4) due to the BLER change over time exceeds the reference value b, the message output means 225 of the system controller 22 may cause the optical disc 1 to be destroyed. A message that warns the user (for example, "This disc cannot be recorded because further rewriting may cause disc destruction." To display a Migihitsuji message to OSD (On Screen Display) display of the display device 20 or the main unit by the process (not shown) (step S10).

  Instead of displaying the message on the display device 20 or the display unit of the main body operation unit, the message may be converted into sound by the speaker 19 and output. In addition, the message may be displayed on the display device 20 or the display unit of the main body operation unit, and may be output as audio by the speaker 19.

  By outputting such a message, the user knows that the optical disc cannot be recorded any more. In addition, since the rewritable optical disk has a wide range of the optimum power of the laser beam, damage to the disk is reduced when recording is performed with a low-power laser beam. Therefore, even if the jitter is a little worse, if the laser power is changed to a low power and recording is performed with a low-power laser beam, even if the optical disk is slightly damaged, it may be possible to further record.

  As described above, rewritable optical discs such as DVD-RW, DVD + RW, and DVD-RAM can repeatedly record, but the standard guarantees 1000 times of DOW (overwrite), but the optical pickup If the recording situation is such that the power at the time of recording of the laser beam emitted from 2 is too strong, the state of the optical disc deteriorates before reaching 1000 times, and eventually the optical disc causes physical destruction. Sometimes. Since the optical disc is recorded as digital information, the playback video does not deteriorate until just before the physical destruction, and it is difficult for the user to determine the disc state.

  Therefore, in this embodiment, every time information is recorded on the optical disk, the jitter of the RF signal and the block error occurrence rate are confirmed, and data on the recording status (recording characteristic data) for repeated recording on the optical disk is constructed. . The recording characteristic data is stored in a reserved area in the lead-in of the optical disk, the disk state is judged from the recording characteristic data, and is detected in advance before physical destruction occurs on the optical disk, It informs the user. Therefore, in the present embodiment, the state of the optical disk can be detected in advance before physical destruction occurs on the optical disk, and it is possible to prevent the loss of valuable information during recording.

  A process for informing the user in advance before physical destruction of the optical disk occurs is a DVD recorder (optical disk) capable of recording / reproducing information on a rewritable optical disk such as DVD-RW, DVD + RW, or DVD-RAM. It can be used for a recording / reproducing apparatus.

It is a block diagram which shows the structure of the optical disk recording / reproducing apparatus which concerns on one Embodiment of this invention. It is explanatory drawing which showed in a graph the example of the relationship between the frequency | count of data rewriting with respect to the rewritable optical disk in the said embodiment, and a jitter. It is explanatory drawing which showed in a graph the example of the temporal change of the jitter detected when the frequency | count of data rewriting is n times with respect to the rewritable optical disk in the said embodiment. It is explanatory drawing which showed an example of the time change of BLER (block error occurrence rate) detected when the frequency | count of data rewriting with respect to the rewritable optical disk in the said embodiment is n times. It is a flowchart for demonstrating the process which detects a disk state in the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical disk 2 Optical pick-up 8 Digital signal processing part 19 Speaker (audio | voice output means)
20 Display device (display means)
22 System controller 221 Jitter detection means 222 Block error occurrence rate detection means 223 Recording characteristic confirmation means 224 Recording characteristic determination means 225 Message output means

Claims (3)

In an optical disc recording / reproducing apparatus for recording / reproducing information on / from an optical disc,
It is determined that the loaded optical disc is a rewritable optical disc, and when the writing of information to the optical disc is started and the writing of information is executed by the optical pickup, the light read from the recorded area of the optical disc Jitter detecting means for detecting jitter of an RF signal that is an output signal of the pickup;
A block error occurrence rate detecting means for detecting a block error occurrence rate in a digital signal processing unit that performs signal demodulation processing and error correction processing according to the data format of the optical disc after converting the RF signal into digital data;
A recording characteristic confirmation means for confirming a recording characteristic due to a time change of the optical disc with reference to the detected jitter or / and block error occurrence rate;
Recording characteristic determination means for determining whether or not the confirmed recording characteristic exceeds a predetermined reference value;
Message output means for causing the display means and / or the sound output means to output a message warning that the optical disc may be destroyed when it is determined that the confirmed recording characteristic exceeds a predetermined reference value. An optical disk recording / reproducing apparatus comprising: a system controller having:   In an optical disc recording / reproducing apparatus that records / reproduces information to / from an optical disc, it is determined that the loaded optical disc is a rewritable optical disc, and writing of information to the optical disc is started, and writing of information is executed by an optical pickup. The signal corresponding to the data format of the optical disc after detecting the jitter of the RF signal, which is the output signal of the optical pickup that has read the information from the recorded area of the optical disc, and converting the RF signal into digital data The block error rate is detected by a digital signal processing unit that performs demodulation processing and error correction processing, and the recording characteristics of the optical disc over time are checked with reference to the detected jitter or / and block error rate. The confirmed recording characteristics are predetermined An optical disc recording / reproduction comprising a system controller for outputting a message warning that the optical disc is likely to be destroyed to a display means and / or an audio output means when it is determined that the threshold value is exceeded apparatus.   The system controller determines that the loaded optical disc is a rewritable optical disc, starts writing information on the optical disc, and starts writing information on the optical pickup from the recorded area of the optical disc. Jitter detection means for detecting jitter of an RF signal that is an output signal of an optical pickup from which information has been read, and after the RF signal is converted into digital data, signal demodulation processing and error correction processing are performed according to the data format of the optical disc Block error occurrence rate detecting means for detecting a block error occurrence rate in a digital signal processing unit, and a recording characteristic for confirming a recording characteristic of the optical disc with time change with reference to the detected jitter or / and block error occurrence rate Confirmation means and the confirmed description Recording characteristic determining means for determining whether or not the characteristic exceeds a predetermined reference value, and when it is determined that the confirmed recording characteristic exceeds a predetermined reference value, the optical disc may be destroyed. 3. The optical disc recording / reproducing apparatus according to claim 2, further comprising message output means for causing a display means and / or an audio output means to output a message warning that there is a message.

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