JP2005310239A - Signal processor and optical disk device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To determine whether a defect such as a fingerprint, damage or dust on the surface of an optical disk left during the recording of optical information in the optical disk is a defect or not to cause the recording mistake of optical information in one RUB by a device capable of highly accurately determining whether the defect such as a fingerprint, damage or dust on the surface of the optical disk made during the recording of the optical information in the optical disk is a defect or not to cause the destruction of an ECC block especially by detecting the level of an erasing section. <P>SOLUTION: A constant voltage circuit having high constant voltage performance is configured to detect a defect signal by using the level change of a recording light reflected on the recording surface of an optical disk caused by the surface defect of the optical disk during the recording of optical information in a disk 102, and to determine the detected defect not from the number but from the integrated value of a time with the defect. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a signal processing apparatus capable of avoiding a recording error on an optical disk due to defects such as fingerprints, scratches, and dust attached to the surface of the optical disk when optical information is recorded on the optical disk, and an optical disk apparatus using the signal processing apparatus. .

  High-density optical disc recording / reproducing apparatuses that record or reproduce data by irradiating a recording medium such as a disc with laser light have appeared. For example, in a recording apparatus corresponding to an optical disc such as CD-R / RW, DVD-R, DVD-R / RW, DVD + RW, or a blue-in disc such as DVR-BULE which is a high-density disc using a short wavelength light source near 450 nm. The track on the optical disk is irradiated with laser light modulated with the recording data, so that the optical data is recorded on the optical disk by, for example, a phase change recording method.

  Here, when data is recorded on the optical disc as described above, if the surface of the optical disc has a defect, the optical disc of 680 nm (such as DVD-R) has a thick disc cover layer, laser light. However, there was no room for fingerprints, scratches, dust, etc. on the surface of the optical disk due to the large beam diameter and the long recording wavelength.

  By the way, since the optical disks themselves such as CD-R / RW, DVD-R, DVD-R / RW, and DVR-BULE are handled in a bare state, the surface of the optical disk is likely to have fingerprints, scratches, dust, etc. Becomes a defect and causes a failure in recording or reading data on the optical disk. For example, the amount of laser light reaching the recording surface of the optical disc is reduced to prevent correct recording, and the amount of reflected light from the optical disc is changed to prevent accurate data reading.

  On the other hand, a 400 nm Blu-ray disc has a recording density about 5 times that of a 680 nm optical disc and the thickness of the disc cover layer is 1/7, so that it is easily affected by defects attached to the disc surface. . Therefore, in order to strengthen the defect determination process in the ECC (Error Check and Correct) part, the 1 ECC part (1 RUB) is enlarged to 64 Kbytes. However, if an unexpected large fingerprint or a large scratch is attached to the disk surface. These defects reach 1/3 of 1RUB, and data of 1RUB is broken. In this case, if there is a fingerprint or scratch in the address area of the RUB and the address data also becomes an error, the recording is stopped, so that no recording error occurs. However, since three RUB addresses are inserted in one RUB and the frequency is as low as 200 KHz, these disturbances are not easily received. However, if the address can be read at the time of recording, even if there is a fingerprint or a scratch on the surface of the optical disc, the address is recorded. In other words, there is a problem that the number of defects existing in one RUB is sequentially recorded regardless of whether or not the number of defects is an amount that causes the data of one RUB to fail.

Therefore, conventionally, a defect detection signal corresponding to a signal having a relatively fast level change corresponding to a defect on the disk recording surface using a reflected light identification unit from a pull-in signal corresponding to the reflected light of the recording medium, and a disk A dust detection signal corresponding to a signal having a relatively slow level change corresponding to the dust on the surface is generated, and the defect detection signal and the dust detection signal are used to compensate the recording of the defective portion with the power of the laser beam ( For example, refer to Patent Document 1), or the data recorded from the recording medium is read by the second light beam after being divided into three, and an error of the read data is detected and the data is recorded from the reflected light. If the result of both the error detection and the defect detection is below a predetermined criterion, the recording is judged as good. , If at least one of the result of the error detection and defect detection exceeds the criterion is one that determines the recording as defective (for example, see Patent Document 2).
JP 2000-31375 A Japanese Patent Laid-Open No. 5-274817

In such a conventional method, defects on the disk recording surface and dust attached to the disk surface can be identified and detected.
However, defects on the surface of a Blu-ray disc include black belt-like defects such as large scratches and large dirt caused by black magic, spot-like defects that expose the recording surface through the disc cover layer, and There are scratch-like defects attached with small scratches and fingerprints, and single defects attached with dust and scratches. The disk reflectivity of these defects is shown in FIG.
In FIG. 5, the reflectance 20% represents the reflectance of the recording surface of the Blu-ray disc, and the reflectance 10% is the reflectance when the recording surface of the Blu-ray disc is amorphized by the light beam. Then, the reflectance of the black belt-like defect 71 decreases to a maximum of zero, and the reflectance of the spot-like defect 72 reaches a maximum of nearly 100%. Further, the reflectance of the scratch-like defect 73 and the single defect 74 is as shown in FIG.

  However, in the conventional method as described above, when various defects having different reflectivities exist on the disk surface as shown in FIG. 5, these defects are reliably detected, and the number of defects present in one RUB is 1 RUB. There is a problem that it is not possible to determine whether or not the amount of data is the amount that causes the failure of the ECC block, that is, whether or not the amount of the data is that of the ECC block.

  The present invention has been made to solve such a conventional problem. When optical information is recorded on the recording surface of the optical disk, defects such as fingerprints, scratches, and dust attached to the surface of the optical disk are ECC blocks. It is an object of the present invention to provide a signal processing apparatus and an optical disk apparatus using the signal processing apparatus, which can detect with high accuracy by detecting the level of an erase section, in particular, whether or not the defect is a defect that breaks down.

  In order to achieve the above object, the present invention records optical information within one RUB (Recording Unit Block) when defects such as fingerprints, scratches, and dust attached to the surface of the optical disc when optical information is recorded on the recording surface of the optical disc. A signal processing device that determines whether or not a defect causes a mistake, and receives optical recording light reflected by a recording surface of the optical disc when optical information is recorded on the optical disc, and converts the optical signal into an RF signal Means, an equalizer circuit for correcting the frequency of the RF signal output from the photoelectric conversion means, an RF processor for extracting an erase section signal from the signal output from the equalizer circuit, and an output from the RF processor A low-pass filter that removes unnecessary high-frequency components of the signal output from the equalizer circuit of the signal, and an RF signal that has passed through the low-pass filter A reference potential generation circuit that generates a reference potential according to the type of defect and compares the reference signal with the defect signal obtained by peak detection of the RF signal that has passed through the low-pass filter, and A defect detection time processing circuit that takes a time when the level is equal to or lower than the reference potential as a defect detection time, and the defect detection time output from the defect detection time processing circuit is set to a predetermined time for each defect. A defect detection time extension circuit that extends and outputs as a defect detection time signal and a defect detection time signal output from the defect detection time extension circuit are sequentially integrated to obtain a total error time value, and the total error time value is expressed in units of 1 RUB An error occurrence time integration circuit that outputs each time, and when the total error time value exceeds the reference value by comparing the total error time value with a preset reference value An error for determining whether or not a defect on the surface of the optical disc is a defect causing a recording error of optical information depending on whether or not the ratio of the time width in one RUB is equal to or larger than a preset value. And an occurrence determination unit.

The present invention also provides an optical disk that is rotationally driven by a driving means, an optical pickup that is moved in the radial direction of the optical disk by a feeding means, and a recording and / or reproducing operation of the rotation of the optical disk and the movement of the optical pickup. An optical disc apparatus comprising: a control means for controlling the optical pickup; and a signal processing means for performing signal processing of recording and / or reproducing operations on the optical disc by the optical pickup, and recording optical information on a recording surface of the optical disc. A signal processing device for determining whether or not a defect such as a fingerprint, a flaw or a dust sometimes attached to the surface of the optical disc is a defect which causes an optical information recording error in one RUB (Recording Unit Block), The signal processing device receives the recording light reflected on the recording surface of the optical disc when recording optical information on the optical disc. Photoelectric conversion means for converting to an F signal; an equalizer circuit for correcting frequency characteristics of the RF signal output from the photoelectric conversion means; and an RF processor for extracting a signal in an erase section from the signal output from the equalizer circuit; A low-pass filter that removes unnecessary high-frequency components of the signal output from the RF processor, and a reference potential generation circuit that integrates the RF signal that has passed through the low-pass filter to generate a reference potential according to the type of defect And a defect signal obtained by comparing the defect signal obtained by peak detection of the RF signal that has passed through the low-pass filter with the reference potential, and taking the time when the level of the defect signal is lower than the reference potential as the defect detection time The detection time processing circuit and the defect detection time output from the defect detection time processing circuit are extended for a predetermined time period for each defect. A defect detection time extension circuit output as a defect detection time signal and a defect detection time signal output from the defect detection time extension circuit are sequentially integrated to obtain a total error time value, and the total error time value is calculated for each RUB unit. The error occurrence time integration circuit to be output is compared with the total error time value and a preset reference value to obtain a time width in which the total error time value exceeds the reference value, and the ratio of this time width in one RUB Error occurrence determination means for determining whether or not a defect on the surface of the optical disc is a defect that causes a recording error in optical information, depending on whether or not is equal to or greater than a preset set value.

  In the signal processing apparatus and the optical disc apparatus of the present invention, the reference potential generation circuit integrates the RF signal obtained by passing through the equalizer circuit, the RF processor, and the low-pass filter to generate a reference potential according to the type of defect, The defect detection time processing circuit compares the defect signal obtained by peak detection of the RF signal passed through the low-pass filter with the reference potential, and the time when the defect signal level is below the reference potential is defined as the defect detection time. Take out. Then, the defect detection time extension circuit extends the defect detection time from the defect detection time processing circuit for each defect by a predetermined time and outputs it as a defect detection time signal. The error occurrence time integration circuit sequentially integrates the defect detection time signals output from the defect detection time extension circuit to obtain a total error time value, and outputs this total error time value for each RUB unit to determine error occurrence. In the means, the total error time value is compared with a preset reference value to obtain a time width in which the total error time value exceeds the reference value, and a ratio of this time width in one RUB is equal to or greater than a preset set value. Whether or not the defect on the surface of the optical disc is a defect that causes an optical information recording error is determined. Therefore, when optical information is recorded on the recording surface of the optical disc, it is possible to determine with high accuracy whether a defect such as a fingerprint, a flaw, or dust attached to the surface of the optical disc is a defect that causes the ECC block to fail. .

  In the best mode of the present invention, it is accurately determined whether or not defects such as fingerprints, scratches, and dust attached to the surface of the optical disk at the time of recording optical information on the recording surface of the optical disk are defects that break the ECC block. In order to achieve the purpose of determination, the reference potential generation circuit integrates the RF signal obtained by passing through the equalizer circuit, the RF processor, and the low-pass filter to generate a reference potential according to the type of defect. The detection time processing circuit compares the defect signal obtained by peak detection of the RF signal that has passed through the low-pass filter with the reference potential, and the time when the defect signal level is below the reference potential is defined as the defect detection time. The defect detection time extension circuit extracts the defect detection time from the defect detection time processing circuit, and outputs a defect detection time signal by extending a predetermined time for each defect.Then, the error occurrence time integration circuit sequentially integrates the defect detection time signals from the defect detection time extension circuit to obtain a total error time value, and outputs the total error time value for each RUB unit. The determination means compares the total error time value with a preset reference value to obtain a time width in which the total error time value exceeds the reference value, and the proportion of this time width in one RUB is equal to or greater than a preset set value. It is determined whether or not the defect on the surface of the optical disc is a defect that causes the ECC block to fail depending on whether or not it exists.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing the overall configuration of a light-based device equipped with a signal processing device according to the present invention, and FIG. 2 is a circuit diagram showing a configuration example of a defect detection time extension circuit in FIG.

A configuration of the optical disc apparatus 101 shown in FIG. 1 will be described.
This optical disk apparatus 101 includes a spindle motor 103 as a driving means for rotationally driving an optical disk 102 which is an optical recording medium such as a DVD ± R / RW, a CD-R / RW, or a Blu-ray disc, an optical pickup 104, A feed motor 105 is provided as drive means for moving the optical pickup 104 in the radial direction of the optical disk 102.
Here, the spindle motor 103 and the feed motor 105 are configured to be driven and controlled by a servo control unit 109 that is controlled based on a command from the system controller 107.

The signal modulator / demodulator & ECC unit 108 shown in FIG. 1 performs signal modulation, demodulation, ECC (error correction code) addition, and error correction processing based on ECC.
In accordance with a command from the system controller 107, the optical pickup 104 applies a light beam from the laser light source 104B to the recording surface of the rotating optical disk 102 through a not-shown optical system and one main spot for recording / reproduction and a tracking surface. It is configured to irradiate two side spots separately. Furthermore, the optical pickup 104 receives various signals output from the photoelectric conversion means (photodiode) 104A of the optical pickup 104 according to the reflected light fluxes corresponding to the main spot and the side spot reflected from the recording surface of the optical disc 102. It is configured to supply to the preamplifier 120.

  The preamplifier 120 amplifies and generates a focus error signal, a tracking error signal, an RF signal and a defect signal based on various signals output from the photoelectric conversion means (photodiode) 104A of the optical pickup 104. For example, a photodiode amplifier 120 for reproducing 100 MHz RF (high frequency signal) is used as 120. The photoelectric conversion means (photodiode) 104A receives the recording light reflected by the recording surface of the optical disc when the optical information is recorded on the optical disc, converts it into an RF signal, and the level changes due to a defect on the surface of the optical disc. The recording light is received and converted into a defect signal.

Further, the signal output from the preamplifier 120 is configured to be input to the servo control unit 109 according to the type of the recording medium, and is output to the signal modulator / demodulator & ECC unit 108, and the signal modulator / demodulator & ECC unit 108. , Predetermined processing such as demodulation and error correction processing based on the output signal from the preamplifier 120 is performed.
Here, if the recording signal demodulated by the signal modulator / demodulator & ECC unit 108 is, for example, for computer data storage, it is sent to the external computer 130 or the like via the interface 111. As a result, the external computer 130 or the like can receive a signal recorded on the optical disc 102 as a reproduction signal. Contrary to the above case, the data from the external computer 130 is modulated by the signal modulator / demodulator & ECC unit 108 and output to the laser control unit 121, and the laser light source is driven so that the data from the external computer 130 is transferred to the optical disk 102. It is configured to be able to write to.

  Also, if the recording signal demodulated by the signal modulator / demodulator & ECC unit 108 is for audio / visual use, it is converted into an analog signal by the D / A conversion unit of the D / A, A / D converter 112 and processed by audio / visual processing. Supplied to the unit 113. Audio / video signal processing is performed by the audio / visual processing unit 113 and transmitted to an external imaging / projection device via the audio / visual signal input / output unit 114. In contrast to the above case, the information captured by the audio / visual processing unit 113 from the external imaging / projection device through the audio / visual signal input / output unit 114 is converted into the A / D of the D / A and A / D converter 112. The signal is converted into a digital signal by the conversion unit, further modulated by the signal modulator / demodulator & ECC unit 108 and output to the laser control unit 121. By driving the laser light source, audio / visual information is received from the external imaging / projection device by the optical disk To get written on.

The optical pickup 104 is connected to a feed motor 105 for moving to a predetermined recording track on the optical disk 102, for example. The servo control unit 109 controls the spindle motor 103, the feed motor 105, and the focusing direction and tracking direction of the biaxial actuator that holds the objective lens of the optical pickup 104.
The laser control unit 121 controls the laser light source 104B in the optical pickup 104, and is configured to control the output power of the laser light source 104B in the recording mode and the reproduction mode.
The PLL circuit 122 shown in FIG. 1 generates a synchronization signal (clock) based on the reproduction RF signal output from the signal modulator / demodulator & ECC unit 108 during reproduction, and the synchronization signal is converted into a D / A and A / D converter 112. In addition, it is detected whether or not there is a light reproduction pulse in a predetermined time zone, and the detected code string is demodulated into a data bit string.

  Further, in FIG. 1, the signal processing apparatus 200 has optical information within one RUB (Recording Unit Block) in which defects such as fingerprints, scratches, and dust attached to the surface of the optical disc when optical information is recorded on the recording surface of the optical disc. The signal processing device 200 is configured to correct an RF signal amplification frequency characteristic of the preamplifier, and an RF signal having a wide band by the equalizer circuit 201. An RF processor 202 that extracts a defect signal in the erase section of the signal, a low-pass filter (LPF) 203 that removes unnecessary high-frequency components from the defect signal extracted by the RF processor 202, and the low-pass filter 203 The peak detection circuit 204 that performs peak detection of the RF signal and the RF signal that has passed through the low-pass filter 203 are integrated. A reference potential generation circuit 205 that generates a reference potential according to the type of the defect, and a defect signal obtained by peak detection of the RF signal that has passed through the low-pass filter 203 are compared with the reference potential to determine the level of the defect signal as a reference. A defect detection time processing circuit 206 for taking out a time that is equal to or lower than the potential as a defect detection time, and the defect detection time output from the defect detection time processing circuit 206 is extended by a predetermined time for each defect. A defect detection time extension circuit 207 output as a detection time signal and a defect detection time signal output from the defect detection time extension circuit 207 are sequentially integrated to obtain a total error time value, and the total error time value is calculated for each RUB unit. The error occurrence time integration circuit 208 that outputs the error to the total error time value is compared with a preset reference value so that the total error time value is a reference value. And determine whether the defect on the surface of the optical disc is a defect that causes an optical information recording error, based on whether or not the ratio of the time width in one RUB is equal to or greater than a preset value. When the error occurrence determination circuit 209 and the error occurrence determination circuit 209 determine that the defect on the surface of the optical disc is a defect that causes an optical information recording error, the determination timing is close to the end of 1 RUB, The output status of the defect processing interrupt command to the replacement RUB control unit 107A provided in the system controller 107 is changed from the next 1RUB to the timing signal indicating the head of the RUB format extracted from the RF signal for each RUB. The latch circuit 210 is configured to hold.

  The recording surface of the optical disk 102 has a well-known alternate RUB (not shown), and the alternate RUB control unit 107A cannot correct errors even if data is recorded with ECC attached to one RUB, and is correct. This is for performing defect processing for recording data to be recorded in one defective RUB that cannot be reproduced in the replacement RUB.

Next, the configuration of the defect detection time extension circuit shown in FIG. 2 will be described.
In FIG. 2, a defect detection time extension circuit 207 sends a pulse signal S2 having a predetermined width (20 μS) with the negative pulse-like defect detection time signal S1 output from the defect detection time processing circuit 206 as a trigger input. The mono multivibrator 205A, a first AND gate 205B that outputs a pulse signal S3 obtained by ANDing the pulse signal S2 of the first mono multivibrator 205A and the defect detection time signal S1, and the pulse signal of the first AND gate 205B A second mono multivibrator 205C that transmits a pulse signal S4 having a predetermined width (20 μS) using S3 as a trigger input, and a signal of a NOT gate 205D that inverts the pulse signal S4 of the second mono multivibrator 205C and the defect detection time signal S1. To output a pulse signal S5 obtained by ANDing 2 AND gate 205E.

Next, FIG. 3 to FIG. 5 are operational waveform diagrams for processing operations for determining whether or not defects such as fingerprints, scratches, and dust attached to the surface of the optical disk 102 are defects that cause optical information recording errors in one RUB. Will be described with reference to FIG.
First, detection of defects such as fingerprints, scratches, and dust attached to the surface of the optical disk 102 is performed using the optical pickup 104. That is, the light beam emitted from the laser light source 104B is applied to the recording surface of the optical disc 102 through an optical system (not shown).
On the other hand, the recording light reflected by the recording surface of the optical disk 102 enters the photoelectric conversion means 104A through an optical system (not shown), is converted into an electric signal by the photoelectric conversion means 104A, and is amplified by the preamplifier 120. The high frequency component attenuated by the preamplifier 120 by the circuit 201 is corrected to the original frequency characteristic, and this is input to the RF processor 202. Here, FIG. 3A shows 6T recording data, and FIG. 3B shows an RF signal corrected by the equalizer circuit 201 (the RF signal when there is a defect is as shown in FIG. 4A). 4B is an enlarged view of the RF processor 202. The RF processor 202 delays the input signal and superimposes it on the original signal as shown in FIG. High-frequency unnecessary components are removed by 203. The peak detection of the superimposed signal is performed by the peak detection circuit 204 as shown in Fig. 3C to extract the signal in the erase section (when there is a defect). The peak detection signal is as shown in FIG.

  This recorded RF signal is input to the peak detection circuit 204 and the reference potential generation circuit 205. And input to the defect detection time processing circuit 206. In the reference potential generation circuit 205, the recording RF signal that has passed through the low-pass filter 203 is integrated to be converted into a DC level signal 33 as shown in FIG. 4D and to a predetermined level according to the type of defect. The signal 34 is shifted to generate a reference potential signal 34 as shown in FIG. Further, the defect detection time processing circuit 206 compares the defect signal obtained by peak detection of the RF signal by the peak detection circuit 204 with the reference potential signal 34, and the level of the defect signal is below the reference potential. Time T is taken out as a defect detection time. A waveform 35 of the defect detection time at this time is shown in FIG.

The defect detection time extension circuit 207 extends the defect detection time output from the defect detection time processing circuit 206 for each defect by a predetermined time, for example, 20 μS, and outputs it as a defect detection time signal. The waveform of the defect detection time signal at this time is shown in FIG.
The extended time 20 μS corresponds to the time from when a signal is input to the lockout due to the occurrence of a defect until the PLL circuit 122 is locked in. Although the negative defect has been described with reference to FIG. 4, since there is a positive defect as shown in FIG.
FIG. 4 (H) shows a timing signal S36 indicating the head of the RUB format extracted from the RF signal for each RUB, and FIG. 4 (I) shows a defect signal S312 generated in the period of 1RUB.

  In addition, the error occurrence time integration circuit 208 sequentially integrates the defect detection time signal output from the defect detection time extension circuit 207 as shown by a waveform 37 in FIG. 4J to obtain a total error time value t. The total error time value t is output every 1 RUB unit. The error occurrence determination circuit 209 compares the total error time value t with a preset reference value to obtain a time width T1 in which the total error time value t exceeds the reference value, and within one RUB of the time width T1. It is determined whether or not the defect on the surface of the optical disc is a defect that causes an optical information recording error depending on whether or not the ratio is greater than a preset value. Here, for example, when it is determined that the defect on the surface of the optical disk is a defect causing an optical information recording error when the ratio of the time width T1 in one RUB is 5% or more, 1RUB determined to be a defect. An interrupt command for recording data to be recorded in the replacement RUB of the optical disk 102 is output to the replacement RUB control unit 107A. When the ratio of the time width T1 in one RUB is 5% or less, it is determined that there is no defect that causes an optical information recording error on the optical disk surface.

  If the error occurrence determination circuit 209 determines that the defect on the surface of the optical disk is a defect that causes an optical information recording error, if the determination timing is close to the end of one RUB, the error is determined to the replacement RUB control unit 107A. The output state of the defect processing interrupt command is held in the latch circuit 210 until a timing signal indicating the head of the RUB format extracted from the RF signal every 1 RUB is generated from the next 1 RUB.

According to this embodiment, the influence of the recording data is eliminated by extracting the output signal of the preamplifier 102 through the equalizer circuit 201, the RF processor 202, and the low-pass filter 203 and extracting the defect signal during the erasing period. Therefore, whether or not defects such as fingerprints, scratches, and dust attached to the surface of the optical disk during recording of optical information on the recording surface of the optical disk are defects that cause an optical information recording error in one RUB, that is, ECC. It is possible to determine with high accuracy whether or not the defect is a failure of the block, and to improve the reliability of the optical disc. When a recording error in units of 1 RUB is detected, the defect processing of shifting to the replacement RUB is possible, so that the recording data can be rewritten to the replacement RUB without error.
In addition, according to the present invention, it is possible to detect a defect signal by utilizing the fact that the recording light reflected by the recording surface of the optical disc changes in level due to a defect on the surface of the optical disc when optical information is recorded on the disc. Since the detected defect is determined not by the number but by the integrated value of the defect time, the processing apparatus can be stably operated without providing an AGC circuit even when the recording power and the optical disk reflectivity are different. it can.

  Next, the operation of the defect detection time extension circuit 207 shown in FIG. 2 will be described with reference to the operation waveform diagram of FIG. When the defect detection time signal S1, which is a negative pulse shown in FIG. 5A and output from the defect detection time processing circuit 206, is input to the first mono multivibrator 205A as a trigger, the first mono multivibrator 205A A pulse signal S2 having a predetermined width (20 μS) shown in FIG. When the pulse signal S2 of the first mono multivibrator 205A and the defect detection time signal S1 are input to the first AND gate 405B, the first AND gate 205B corresponds to the logical product of both signals as shown in FIG. A pulse signal S3 is output. Further, when the pulse signal S3 of the first AND gate 205B is input as a trigger to the second mono multivibrator 205C, the second mono multivibrator 205C outputs a pulse signal S4 having a predetermined width (20 μS) shown in FIG. Is sent out. When the pulse signal S4 of the second mono multivibrator 205C and the signal of the NOT gate 205D that inverts the defect detection time signal S1 are input to the second AND gate 405E, the second AND gate 205E generates a logical product of both signals. The corresponding pulse signal S5 shown in FIG. 5C is output.

  According to such a signal processing apparatus including the defect detection time extension circuit 207 shown in FIG. 2, the extended time 20 μS is from when a signal is input to the PLL circuit 122 due to the occurrence of a defect until it is locked in. Since the data error corresponds to the time, the defect time is determined. Therefore, for the defect of 20 μS or less, the magnitude of the defect pulse is determined without adding the time, so that the addition pulse is not generated. Time can be added only to defects larger than 20 μS.

It is a block diagram which shows the structure of the whole optical disk apparatus provided with the signal processing apparatus concerning this invention. FIG. 2 is a circuit diagram showing a configuration example of a defect detection time extension circuit in FIG. 1. It is a wave form diagram which shows operation | movement of the equalizer circuit and RF processor which were shown in FIG. It is a wave form diagram which shows operation | movement of the signal processing apparatus shown in FIG. FIG. 3 is a waveform diagram showing an operation of the defect detection time extension circuit shown in FIG. 2. It is explanatory drawing showing the relationship between defects, such as a fingerprint attached to the surface of an optical disk, a crack, and dust, and the disk reflectivity of these defects.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Optical disk apparatus, 102 ... Optical disk, 103 ... Spindle motor, 104 ... Optical pick-up, 104A ... Photoelectric conversion means, 104B ... Laser light source, 105 ... Feed motor, 107 ... System controller, 107A ... ... Alternating RUB control unit, 108 ... Signal modulator / demodulator & ECC unit, 109 ... Servo control unit, 112 ... D / A, A / D converter, 120 ... Preamplifier, 122 ... PLL circuit, 200 ... Signal Processing unit 201... Equalizer circuit 202... RF processor 203. Low pass filter 204. Peak detection circuit 205. Reference potential generation circuit 206 .. defect detection time processing circuit 207. Detection time extension circuit, 208... Error occurrence time integration circuit, 209... Error occurrence determination circuit, 210. Circuit.

Claims (8)

Whether or not defects such as fingerprints, scratches, and dust attached to the surface of the optical disc when optical information is recorded on the recording surface of the optical disc are defects that cause an optical information recording error in one RUB (Recording Unit Block). A signal processing device for determining
Photoelectric conversion means for receiving recording light reflected by the recording surface of the optical disc when the optical information is recorded on the optical disc and converting it into an RF signal;
An equalizer circuit for correcting a frequency characteristic of the RF signal output from the photoelectric conversion means;
An RF processor for extracting a signal in an erase section from a signal output from the equalizer circuit;
A low-pass filter for removing unnecessary high-frequency components of the signal output from the RF processor;
A reference potential generation circuit that integrates the defect signal that has passed through the low-pass filter and generates a reference potential according to the type of defect;
A defect detection time in which a defect signal obtained by peak detection of an RF signal that has passed through the low-pass filter is compared with the reference potential, and a time when the level of the defect signal is equal to or lower than the reference potential is extracted as a defect detection time. A processing circuit;
A defect detection time extension circuit that extends the defect detection time output from the defect detection time processing circuit for each defect and outputs a predetermined detection time signal as a defect detection time signal;
An error occurrence time integration circuit that sequentially integrates the defect detection time signals output from the defect detection time extension circuit to obtain a total error time value and outputs the total error time value for each RUB unit;
The total error time value is compared with a preset reference value to obtain a time width in which the total error time value exceeds the reference value, and a ratio of the time width in one RUB is equal to or greater than a preset set value. An error occurrence determination means for determining whether or not the defect on the surface of the optical disc is a defect that causes an optical information recording error,
A signal processing apparatus comprising:   The recording surface of the optical disc has a replacement RUB, and includes a replacement RUB control unit for recording data to be recorded in one defective RUB in the replacement RUB, and the error occurrence determination means includes 1 RUB of the time width. When the percentage of the optical disk in the optical disk is 5% or more, it is determined that the defect on the optical disk surface is a defect that causes an optical information recording error, and when it is determined to be a defect, recording is performed on 1 RUB that is determined to be a defect. 2. The signal processing apparatus according to claim 1, wherein a defect processing interrupt command for recording data to be recorded in the replacement RUB is output to the replacement RUB control unit.   The recording surface of the optical disc has a replacement RUB, and includes a replacement RUB control unit for recording data to be recorded in one RUB having a defect in the replacement RUB. When the determination timing when it is determined that the defect is a defect causing an optical information recording error is performed near the end of one RUB, the output state of the defect processing interrupt command to the replacement RUB control unit is set for each RUB. 2. The signal processing apparatus according to claim 1, further comprising: a latch circuit that holds a timing signal indicating the head of the RUB format extracted from the RF signal until it is generated from the next one RUB.   A PLL circuit that generates a synchronization signal based on the RF signal to be reproduced; and in the defect detection time extension circuit, a predetermined time for extending the defect detection time for each defect is determined by the occurrence of the defect. The signal processing apparatus according to claim 1, wherein the time is from when the circuit is locked out to when the circuit is locked in. An optical disc that is rotationally driven by a drive means;
An optical pickup moved in the radial direction of the optical disk by a feeding means;
Control means for controlling the rotation of the optical disc and the movement of the optical pickup in accordance with the recording and / or reproducing operation;
An optical disc device comprising: signal processing means for performing signal processing of recording and / or reproducing operations on the optical disc by the optical pickup;
Whether or not defects such as fingerprints, scratches, and dust attached to the surface of the optical disc when optical information is recorded on the recording surface of the optical disc are defects that cause an optical information recording error in one RUB (Recording Unit Block). A signal processing device for determining
The signal processing device includes:
Photoelectric conversion means for receiving recording light reflected by the recording surface of the optical disc when the optical information is recorded on the optical disc and converting it into an RF signal;
An equalizer circuit for correcting a frequency characteristic of the RF signal output from the photoelectric conversion means;
An RF processor for extracting a signal in an erase section from a signal output from the equalizer circuit;
A low-pass filter for removing unnecessary high-frequency components of the signal output from the RF processor;
A reference potential generation circuit that integrates the defect signal that has passed through the low-pass filter and generates a reference potential according to the type of defect;
A defect detection time in which a defect signal obtained by peak detection of an RF signal that has passed through the low-pass filter is compared with the reference potential, and a time when the level of the defect signal is equal to or lower than the reference potential is extracted as a defect detection time. A processing circuit;
A defect detection time extension circuit that extends the defect detection time output from the defect detection time processing circuit for each defect and outputs a predetermined detection time signal as a defect detection time signal;
An error occurrence time integration circuit that sequentially integrates the defect detection time signals output from the defect detection time extension circuit to obtain a total error time value and outputs the total error time value for each RUB unit;
The total error time value is compared with a preset reference value to obtain a time width in which the total error time value exceeds the reference value, and a ratio of the time width in one RUB is equal to or greater than a preset set value. An error occurrence determination means for determining whether or not the defect on the surface of the optical disc is a defect that causes an optical information recording error,
An optical disc apparatus comprising:   The recording surface of the optical disc has a replacement RUB, and includes a replacement RUB control unit for recording data to be recorded in one defective RUB in the replacement RUB, and the error occurrence determination means includes 1 RUB of the time width. When the percentage of the optical disk in the optical disk is 5% or more, it is determined that the defect on the optical disk surface is a defect that causes an optical information recording error, and when it is determined to be a defect, recording is performed on 1 RUB that is determined to be a defect. 6. The optical disc apparatus according to claim 5, wherein a defect processing interrupt command for recording data to be recorded in the replacement RUB is output to the replacement RUB control unit.   The recording surface of the optical disc has a replacement RUB, and includes a replacement RUB control unit for recording data to be recorded in one defective RUB on the replacement RUB. When the determination timing when it is determined that the defect is a defect causing an optical information recording error is performed near the end of one RUB, the output state of the defect processing interrupt command to the replacement RUB control unit is set for each RUB. 6. The optical disk apparatus according to claim 5, further comprising a latch circuit that holds a timing signal indicating the head of the RUB format extracted from the RF signal until it is generated from the next one RUB.   A PLL circuit that generates a synchronization signal based on the RF signal to be reproduced; and in the defect detection time extension circuit, a predetermined time for extending the defect detection time for each defect is determined by the occurrence of the defect. 6. The optical disk apparatus according to claim 5, wherein the time is from when the circuit is locked out to when the circuit is locked in.

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