KR19980039975A - DVD recorder and player - Google Patents

Abstract

The present invention relates to a recording and reproducing apparatus of a DVDR system, wherein when a groove of a specific track of an optical disc is broken, the device can record the data for identifying the corresponding groove damage section and skip the groove damage section during playback. to be.

Description

DVD recorder and player

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording and reproducing apparatus for recording, erasing, and reproducing a DVDR (Digital Video Disc Recorder) system, particularly for recording and reproducing data when a groove of an optical disc is damaged.

In general, optical discs are CD-only CDs, CD-ROMs, video discs, etc., which can be read only by the user. Information can be recorded once, and the recorded information can be read several times, but cannot be erased or rewritten. It can be divided into a recording type and an erased rewrite type that can repeatedly record, erase, and reproduce information.

Play-only type CD is already replacing the existing LP record board in the sound industry, CD-ROM which is a medium that can be searched when necessary by recording a large amount of information that needs to be widely spread such as encyclopedia, and recently in Korea Video discs and the like, which are rapidly expanding, have already been put into practical use and are in the dissemination stage. Additional recordable optical discs can be used for hospitals and large documents that need to store information such as X-rays, NMR-CTs, ultrasound tomography, and patient care cards. It is used for necessary public offices and mineral veins such as mines and oil fields.

The erasing rewritable optical disc has a magneto-optical type and a phase change type. The phase change type records using crystalline / amorphous reversible changes in the process of heating and cooling the micro part of the medium using a laser, and the information is reflected by the difference in reflectance between the two phases. I am using a method to read it.

1 and 2 show a diagram for explaining a recording, erasing, and reproducing method for such an erased rewritable optical disc.

In general, recording of an erased rewritable optical disc is performed instantaneously until the magnetic thin film magnetized in one direction perpendicular to the thin film surface as shown in FIG. 1A is near the Curie temperature by the laser focused light pulse a as shown in FIG. When heated, the coercive force of the heated micro part is reduced. At this time, only the laser irradiation part heated by the weak magnetic field applied in the direction opposite to the medium magnetization direction is reversed. When the laser pulse is turned off and cooled to room temperature, only this part remains as a stable inverse magnetic field bit and information is recorded.

The erasing is performed by heating the portion where the information is recorded as shown in FIG. 1B by the laser beam b as shown in FIG. 2, and then applying the direction of the external magnetic field during cooling to have the original magnetization direction. By doing so.

On the other hand, reading of the recorded information is performed by using a laser light and a polarizer which are weaker than at the time of recording as shown in FIG. 2 (c). The magneto-optical Kerr effect which rotates left and right with respect to the polarization direction of this incident light is used (refer FIG. 1 (C)). That is, the polarization direction of the reflected light is rotated counterclockwise when the magnetization direction of the material is downward, and clockwise when it is upward, so that the reflected light passes through the two reflected beams with the analyzer set in advance in a direction that hardly passes the reflected polarization in the unrecorded portion. Then, the reflected light of the unrecorded part has a weak light quantity, and the reflected light of the recorded part passes through the analyzer and is converted into a strong signal of light, which is read by the digital signals '0' and '1' using a photodetector. Done.

As described above, a system for recording, erasing, and reproducing the erase rewritable optical disc is commonly referred to as a DVDR system.

On the other hand, the surface for recording and reproducing of the erasing rewritable optical disc is formed by a groove, in which data is written into or read from the groove. Therefore, when the groove of a specific track is broken, data cannot be recorded on a desired track, which causes a problem when playing an optical disc.

The present invention has been made to solve the above problems, and when the groove of a particular track is broken, the data indicating this at the beginning and the end of the damaged area is recorded so that the data indicating the breakage during data recording and playback is recorded. It is an object of the present invention to provide a recording and reproducing apparatus in which a skip is made so that the groove can record and reproduce even a damaged disk.

SUMMARY OF THE INVENTION The present invention provides a DVDR system for recording and reproducing data on an optical disc in which a groove of a specific track is damaged in order to achieve the above object, comprising: an optical pickup unit for reading data from the optical disc and recording data on the optical disc; A tracking error detector for detecting a tracking error generated during reading and writing operations of the optical pickup unit and outputting a tracking error signal corresponding thereto; A low pass filter to low pass filter the tracking error signal; An A / D converter converting the output of the low pass filter into digital; A tracking servo unit for controlling a track trace and a track jump of the optical pickup unit; A reproduction unit for reproducing the data read by the optical pickup unit; A synchronization signal detection unit for detecting a synchronization signal among data reproduced in the reproduction unit; A groove breakage data detection unit for detecting groove breakdown start data and groove breakage end data among data reproduced by the reproducing unit; A recording unit which allows data provided from the outside to be recorded on the optical disc by the optical pickup unit; Detects whether the optical disc is damaged by the tracking error signal provided from the A / D converter, and sets the start and end of the groove damage section based on the synchronization signal provided by the sync signal detector, and then grooves are damaged. The recording unit is controlled to record groove break start data and groove break end data, respectively, at the beginning and the end of a section, and the groove break is performed based on the groove break section start and end data provided from the groove break data detecting unit during playback. And a control unit for controlling the reproducing unit to skip a section.

1 and 2 are diagrams for explaining a recording, erasing, and reproducing method of an erased rewritable optical disc.

3 shows a recording and reproducing apparatus according to a preferred embodiment of the present invention;

<Description of the code | symbol about the principal part of drawing>

100: optical disk 110: optical pickup

120: tracking error detection unit 130: low pass filter

140: A / D conversion unit 150: tracking servo unit

160: playback unit 170: synchronization signal detection unit

180: groove damage data detection unit 190: recording unit

200: control unit

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

3 shows a recording and reproducing apparatus according to a preferred embodiment of the present invention.

In FIG. 3, the recording and reproducing apparatus detects a tracking error of the optical disc 100, the optical pickup unit 110 that reads data from the optical disc 100, and the optical pickup unit 110, and tracks corresponding tracking errors. A tracking error detector 120 for outputting an error signal, a low pass filter 130 for low-pass filtering the tracking error signal, and an A / D (Analoge / Digital) converter for converting the output of the low pass filter 130 to digital ( 140, a tracking servo unit 150 that controls track traces and track jumps of the optical pickup unit 110, a reproduction unit 160, and a reproduction unit 160 which reproduce data read by the optical pickup unit 110. The synchronization signal detection unit 170 for detecting a synchronous signal among the data reproduced in the data, the groove damage data detection unit 180 for detecting groove break start data and groove break end data in the data reproduced by the playback unit 170, from the outside. Data provided by the optical pickup unit 110 The groove breakage section of the optical disc 100 based on the tracking error signal detected by the recording unit 190 and the A / D converter 140 and the synchronization signal detected by the synchronization signal detection unit 170 to be recorded. The control unit controls to record the groove breakage start data and the groove breakage end data in the groove breakage section, and to skip the groove breakage section based on the groove breakage section start and end data from the groove breakage data detection unit 180 during playback. It consists of 200.

The operation description of the recording and reproducing apparatus configured as described above is as follows.

First, in the normal recording mode, the recording unit 190 compresses and modulates data provided from the outside by a conventional compression and modulation algorithm, and provides the optical pickup unit 110 to the optical pickup unit 110. Data provided from the CD is recorded on the optical disc 100.

As the optical pickup unit 110 is driven, the tracking error detection unit 120 detects the tracking error of the optical pickup unit 110 and provides a tracking error signal corresponding thereto to the low pass filter 130. 130 performs low pass filtering on the tracking error signal and provides it to the A / D converter 140, and the A / D converter 140 converts the output of the low pass filter 130 to digital and provides it to the controller 200. .

The controller 200 detects a groove breakage section of the optical disc 100 by detecting a signal provided from the A / D converter 140. That is, when the groove for the specific track of the optical disc 100 is broken, the tracking error signal in the groove break section is rapidly increased, and thus the output of the low pass filter 130 will have a predetermined value or more.

Therefore, when the groove breakage section is detected based on the output of the A / D conversion unit 140, the control unit 200 controls the recording unit 180 to stop the recording operation and then reverse the track jump command to the tracking servo unit 150. To provide. The tracking servo unit 150 performs a track jump backward by a predetermined section from the current track position of the optical disc 100 when the reverse track jump command is provided from the controller 200.

When the reverse track jump is completed, the controller 200 controls the playback unit 160 to perform the playback. The playback unit 160 drives the optical pickup unit 110 under the control of the controller 200, and the optical pickup unit 110 reads data from the optical disc 100 and provides the data to the playback unit 160. The reproduction unit 160 demodulates, expands and outputs the data provided from the optical pickup unit 110, and the synchronization signal detection unit 170 detects a synchronization signal among the reproduced data and provides the same to the controller 200. At this time, if the current playback section is the groove break section, the synchronization signal will not be detected. Therefore, if the synchronization signal detection unit 170 does not detect the synchronization signal within a predetermined time, the control unit 200 determines that the current playback section is a groove breakage section and controls the playback unit 160 to stop the playback operation. 150, a reverse jump command is provided.

The playback unit 160 stops the playback operation under the control of the controller 200, and the tracking servo unit 150 performs a reverse jump. When the reverse track jump is completed, the controller 200 controls the playback unit 160 to perform the playback, and then searches whether the signal indicating that the sync signal has been detected is provided from the sync signal detector 170.

If a signal indicating that the synchronization signal is detected from the synchronization signal detection unit 170 is not provided within a predetermined time, the controller 200 controls the aforementioned reverse jump operation to be repeatedly performed, and the synchronization signal from the synchronization signal detection unit 170 within a predetermined time. When a signal indicating that is detected is provided, the controller 200 provides the groove break start data to the recording unit 190 and controls the recording unit 190 to perform a recording operation. The recording unit 190 drives the optical pickup unit 110 so that groove break start data is recorded on the optical disc 100 under the control of the control unit 200. The optical pickup unit 110 records the groove break start data in the groove break start section of the optical disc 100.

Meanwhile, the controller 200 controls the recording unit 190 to stop the recording operation after a predetermined time after providing the groove break start data to the recording unit 190, and provides a forward jump command to the tracking servo unit 150. . The tracking servo unit 150 may perform a forward jump under the control of the controller 200.

When the forward jump is completed, the controller 200 controls the playback unit 160 to perform the playback. The playback unit 160 drives the optical pickup unit 110 under the control of the controller 200, and the optical pickup unit 110 reads data from the optical disc 100 and provides the data to the playback unit 160. The sync signal detector 170 detects a sync signal from the reproduced data and provides the sync signal to the controller 200. At this time, if the current playback section is the groove break section, the synchronization signal will not be detected. Therefore, if the synchronization signal detection unit 170 does not detect the synchronization signal within a predetermined time, the control unit 200 determines that the current playback section is a groove breakage section and controls the playback unit 160 to stop the playback operation. 150, forward jump command.

The playback unit 160 stops the playback operation under the control of the controller 200, and the tracking servo unit 150 performs a forward track jump. When the forward track jump is completed, the controller 200 controls the playback unit 160 to perform the playback and then searches whether the signal indicating that the sync signal has been detected is provided from the sync signal detector 170.

If a signal indicating that a synchronization signal has been detected from the synchronization signal detector 170 is not provided within a predetermined time, the controller 200 controls the aforementioned forward jump operation to be repeatedly performed, and the synchronization signal from the synchronization signal detection unit 170 within a predetermined time. When a signal indicating that is detected is provided, the controller 200 provides the groove break end data to the recording unit 190 and controls the recording unit 190 to perform a recording operation. The recording unit 190 drives the optical pickup unit 110 so that groove break end data is recorded on the optical disc 100 under the control of the controller 200. The optical pickup unit 110 records the groove break end data in the groove break start section of the optical disc 100.

When groove break end data is recorded, the controller 200 controls the recording unit 200 to record a normal recording operation, that is, data provided from the outside.

As described above, an operation of reproducing the optical disc 100 in which groove break start and end data is recorded in the groove break section of the optical disc 100 in which the groove of a specific track is broken will be described.

First, during reproduction, the optical pickup unit 110 reads data from the optical disc 100 and provides the data to the reproduction unit 160. The reproduction unit 160 demodulates, decompresses, and outputs data provided from the optical pickup unit 110. The groove damage data detector 180 detects whether the groove damage start data is reproduced among the reproduced data and provides the result to the controller 200.

The groove breakage data detector 180 provides a signal indicating the groove breakage start data to the control unit 200 during the playback, and when the groove breakage start data is detected, the control unit 200 controls the playback unit 160 to reproduce the groove breakage start data. After the operation is stopped, a forward jump command is provided to the tracking servo unit 150.

When the forward track jump is completed, the controller 200 controls the playback unit 160 to perform playback, and then searches whether the signal indicating that groove damage end data has been detected is provided from the groove damage data detector 180.

If a signal indicating that the groove breakage end data has been detected from the groove breakage data detection unit 180 is not provided within a predetermined time period, the controller 200 controls the aforementioned forward jump operation to be repeatedly performed and detects the groove breakage end data within a predetermined time period. If a signal indicating that the information is provided is provided, the controller 200 controls the playback unit 160 to perform normal playback.

As described above, in the present invention, when the groove of a specific track of an optical disc is broken, data indicating this at the beginning and end of the corresponding groove break section is recorded so that the groove break section is skipped during playback so that the groove is broken. There is an effect to enable recording and playback.

Claims (1)

In a DVDR system for recording and playing back data on an optical disc whose groove of a particular track is broken: An optical pickup unit (110) for reading data from the optical disc and recording the data on the optical disc; A tracking error detection unit 120 for detecting a tracking error generated during reading and writing operations of the optical pickup unit 100 and outputting a tracking error signal corresponding thereto; A low pass filter 130 for low-pass filtering the tracking error signal; An A / D converter 140 for converting the output of the low pass filter 130 into digital; A tracking servo unit 150 for controlling a track trace and a track jump of the optical pickup unit 110; A reproduction unit 160 for reproducing the data read by the optical pickup unit 110; A synchronization signal detection unit 170 for detecting a synchronization signal among data reproduced by the reproduction unit 160; A groove breakage data detection unit 180 for detecting groove breakdown start data and groove breakdown end data among data reproduced by the reproducing unit 170; A recording unit 190 for allowing data provided from the outside to be recorded on the optical disc by the optical pickup unit 110; Detects whether the optical disc is damaged by the tracking error signal provided from the A / D converter 140, and starts and ends the groove break interval based on the synchronization signal provided by the synchronization signal detector 170. The recording unit 190 is controlled so that groove break start data and groove break end data are recorded at the beginning and end of the groove break section, respectively, and the groove provided from the groove break data detection unit 180 during reproduction. And a control unit (200) for controlling the playback unit (160) to skip the groove damage section based on the damage section start and end data.