KR20030004520A - Method distinctting non writting area in an optical disk - Google Patents

Abstract

PURPOSE: A method for discriminating a non-written area on an optical disk is provided to get out of the non-written area within a short time by promptly discriminating a written area and the non-written area in a multi-session disk, thereby reducing a seek time or a TOC reading time. CONSTITUTION: A method for discriminating a non-written area on an optical disk includes the steps of detecting a peak-to-peak level of a traverse tracking error in a written area(S200), calculating a mean tracking error level(S210), confirming whether the tracking error level detected in a seek operation exceeds the range of the mean tracking error level(S220), discriminating the area as the non-written area if the tracking error level exceeds the range of mean tracking error level(S230), random moving an optical pickup in an inner peripheral direction to get out of the non-written area(S240), writing a final session message in the TOC area of the session right before the non-written area(S250).

Description

METHOD DISTINCTTING NON WRITTING AREA IN AN OPTICAL DISK}

The present invention relates to a method for discriminating an unrecorded area on an optical disc, and more particularly, to an unrecorded area discrimination method for reducing a seek time or a TOC reading time in an optical disc that has not been closed. It is about.

Today's audio compact discs have become an essential audio medium, with the popularity of compact disc players gaining popularity with the spread of compact disc players.

The audio compact disc includes CD-ROM, CD-DA, CD-R, CD-RW, and the like, of which CD-R and CD-RW are rewritable optical discs. In other words, the CD-R disc can be written only once, and the CD-RW disc can be rewritten several times. Each disc complies with the standard format defined in the CD series, ie, redbooks, yellowbooks, etc., making it compatible to read from CD-ROM drives, CD-R drives, and CD-RW drives.

The general driving principle of the optical recording and reproducing system is as follows.

In the optical recording / reproducing system, a circular optical disk of about 12 cm is used, and a predetermined hole is formed in the center of the optical disk to mount a rotating shaft, and a recording track of a rotating source extending in the circumferential direction is formed therein. The recording track can be considered as one long line, and pits and lands having a constant size are alternately formed on the recording track. The lengths of the pits and lands are 3T to 11T in length, and the combination of these nine lengths stores digital data.

In this case, the focused laser beam is accurately irradiated on the recording track of the stored digital data, and the reflected light is detected to determine the state of the recording track and convert the data into a digital signal to read the data.

At this time, the laser beam is mounted on an assembly called a pickup so as to be movable in the radial direction of the optical disc, and can read all data recorded on the optical disc as the optical disc rotates.

CD-R0M and CD-DA discs, on the other hand, are already read-only discs where pits and land rows are already formed on the recording tracks, while CD-R and CD-RW discs have slightly different structures. In the CD-R and CD-RW discs, a material having a reflective property changed by laser irradiation is coated on the surface of the disc. Therefore, when a laser beam having energy of a certain level or more is irradiated onto the recording surface, the material at the spot where the light spot is formed changes its reflection characteristic according to the laser level, so that the pit and land rows are newly formed regardless of the previous state. This will be possible.

The recording area of the read-only or recordable optical disc is divided into a lead-in area, a program area, and a lead-out area. A recordable optical disc has a PMA area and a PCA area in front of the first lead-in area. More exists.

The lead-in area is located in front of the program area, and has a data structure called TOC (TOC). In this TOC area, track information recorded in the program area is recorded based on information of tracks recorded in the program area. Recognize the existence of these people and find their location.

The program area is an area capable of storing actual meaningful data and is composed of one or more track areas. That is, several tracks exist in the program area, and in the case of an audio CD, one song is typically stored in one track.

The lead-out area is a spare area outside the program area, and records information indicating that the program area is finished.

The lead-in area, the program area, and the lead-out area are collectively called a session, and several sessions can be formed on one disc, which is called a multisession.

In such a multi-session, there is an optical disk in a state where the disk is not closed. As described above, when the pickup enters the unrecorded area in the optical disk that is not closed, it is determined that the unrecorded area is long, and the time taken out from the unrecorded area is long.

Therefore, when a user uses an optical disc with an unrecorded area, there is a problem in that it is unnecessary to determine that it is an unrecorded area and seek to the recording area.

The present invention calculates an average tracking error level in the recording area in order to effectively solve the above-described problems of the prior art, so as to check whether the detected tracking error level is out of the average tracking error level, or in a time-locked phase locked loop (PLL). It is an object of the present invention to provide a method for determining an unrecorded area of an optical disc which determines whether a locked area is locked or not to determine whether it is a recording area or an unrecorded area.

1 is a flowchart illustrating a method of determining an unrecorded area according to whether a phase locked loop is locked according to an exemplary embodiment of the present invention.

2 is a flowchart illustrating a method of determining an unrecorded area according to a tracking error level according to another embodiment of the present invention.

3A is a diagram showing that the phase synchronization loop is locked in the recording area of the optical disc.

3B is a diagram showing that the phase locked loop does not lock when entering the unrecorded area of the optical disc.

One aspect of the present invention for achieving the above technical problem is a step of checking whether the phase synchronization loop is locked within a predetermined time when the servo is driven;

(B) if the phase locked loop is not locked, determining that it is an unrecorded area.

Another aspect of the present invention for achieving the above technical problem is the step of (D) detecting the tracking error level in the recording area, calculating the average tracking error level;

(E) checking whether a tracking error level detected during SEEK is out of the range of the average tracking error level;

(F) if it is found out of the range of the average tracking error level, determining that it is an unrecorded area.

Hereinafter, a method of determining an unrecorded area on an optical disc according to a preferred embodiment of the present invention will be described in detail with reference to FIGS. 1 and 3.

Preferred embodiments of the method for determining an unrecorded area on an optical disc according to the present invention include a method for determining an unrecorded area using a tracking error level and a method for discriminating an unrecorded area depending on whether or not a phase locked loop is locked.

In this specification, a method of determining an unrecorded area on an optical disc will be described in detail based on the two embodiments.

1 is a flowchart illustrating a method of determining an unrecorded area according to whether or not a phase locked loop is locked according to an exemplary embodiment of the present invention.

As shown in Fig. 1, in a reproduction-only optical recording player, when the CD-R or CD-RW without disc closing is to be played back, the CD-R or CD-RW is inserted into and mounted on the optical recording player ( S100).

Thereafter, the thiosci area of the optical disk is seeked (S110), and a check is performed to determine whether a phase locked loop is locked during seek (S120).

If the phase synchronization rope is not locked in the checking step (S120), it is determined as an unrecorded area (S130). In this case, ATIP decoding is not possible, so the phase locked loop is not locked.

In addition, when it is determined as an unrecorded area, since the EFM (Eight to Fourteen Modulation) signal for controlling the spindle is not detected, control of the spindle is difficult. Typically, the linear velocity of the spindle is approximately 1.2 to 1.4 m / s, with 1.3 m / s being most suitable. However, as described above, the EFM signal is not detected in the unrecorded area and thus the linear velocity of the spindle cannot be controlled, so that data detection and position detection are not easy.

Therefore, in the unrecorded area, the pickup is randomly moved in the inner circumferential direction until it enters the recording area (S140).

In this case, in the case of an optical disc recorded by multisession, the Nth session has TOC information of the N + 1th session. Therefore, when the N + 1th session is the unrecorded area, the last session message indicating that the N + 1 session is the unrecorded area is recorded in the TOC area of the Nth session, and the TOC read operation is completed (S150).

On the other hand, when the phase synchronization loop is locked in the checking step (S120), it is determined as the recording area (S160), and the normal optical disc read operation may be performed (S170).

2 is a flowchart illustrating a method of determining an unrecorded area according to a tracking error level according to another embodiment of the present invention.

As shown in Fig. 2, when reproducing predetermined data recorded on the optical disc, the peak-to-peak level of the traverse tracking error in the recording area is detected (S200), and then the average tracking error level is detected. To calculate (S210).

Then, the tracking error level is detected during the seek operation. In this case, the seek operation detects the tracking error level while only the focus servo is driven to check whether the seek operation is out of the range of the average tracking error level (S220).

If the tracking error level detected during the seek is out of the range of the average tracking error level in the checking step (S220), it is determined as an unrecorded area (S230). At this time, since the tracking error level is detected by the three-beam method, in the unrecorded area, the traverse tracking level is small in the state where only the focus servo is driven.

Then, the pickup is randomly moved in the inner circumferential direction in order to exit the unrecorded area (S240).

In this case, in the case of an optical disc recorded by multisession, the Nth session has TOC information of the N + 1th session. Therefore, when the N + 1th session is the unrecorded area, the N + 1 session is recorded in the TOC area of the Nth session, and then the TOC read operation is completed (S250).

On the other hand, when the tracking error level detected during the seek is within the range of the average tracking error level in the checking step (S220), it is determined as a recording area (S260), and a normal read operation is performed (S270).

3A is a diagram showing that the phase synchronization loop is locked in the recording area of the optical disc. In this case, the tracking error is well detected in the recording area, so that the control of the spindle is easy. Thus, the phase locked loop is locked.

3B is a diagram showing that the phase locked loop does not lock when entering the unrecorded area of the optical disc. In this case, since no tracking error is detected during seek, the EFM signal is not detected and the phase locked loop is not locked.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. . Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, according to the method of determining an unrecorded area on an optical disc of the present invention, a seek time is determined by quickly judging a recorded area and an unrecorded area in a multisession disc that has not been closed, and exiting the unrecorded area in a short time. This can reduce or reduce TOC reading time.

Claims (7)

(A) if the servo is driven, checking whether the phase-locked loop is locked within a predetermined time; (B) when the phase locked loop is not locked, determining the unrecorded area as an unrecorded area. The method of claim 1, wherein the next step in which step (B) is performed (B1) An unrecorded area discrimination method on an optical disc, characterized in that the pickup is moved to a recording area of the inner circumference. The method of claim 2, wherein the next step of the step (B1) (B2) The unrecorded area discrimination method on the optical disc, characterized in that the last session message indicating the last session is recorded in the TOC area of the immediately preceding session of the unrecorded area when the optical disc is composed of multisessions. (D) detecting a tracking error level in the recording area to calculate an average tracking error level; (E) checking whether a tracking error level detected during SEEK is out of the range of the average tracking error level; (F) if it is determined that the average tracking error level is out of a range, determining the unrecorded area as claimed in the non-recorded area on the optical disc. The method of claim 4, wherein And a tracking error level detected during the seek is detected while only the focus servo is driven. The method according to claim 4, wherein the next step in which step (F) is performed (F1) An unrecorded area discrimination method on an optical disc, characterized in that the pickup is moved to a recording area of the inner circumference. The method of claim 6, wherein the next step in which step (F1) is performed (F2) The unrecorded area discrimination method on the optical disc, characterized in that the last session message indicating the last session is recorded in the TOC area of the immediately preceding session of the unrecorded area when the optical disc is composed of multisessions.