KR19990084719A - Track width calculation method of optical disc - Google Patents

Abstract

The present invention relates to a track width calculation method of an optical disk for detecting a track width of an optical disk. More particularly, the present invention relates to a track width calculation method of an optical disk. Determining a predetermined position to move the optical pickup in the area, moving the optical pickup to the determined predetermined position, calculates the number of tracks corresponding to the traveled distance to detect one track width, and then to the target track in the future By calculating the movement distance, it is possible to calculate the width of a single track accurately regardless of the size of data recorded on the optical disk, and calculate the track width of the optical disk to make the access time of the optical disk the same regardless of the track width of the optical disk. A method comprising: a first step of determining a predetermined distance at which an optical pickup will move from playlist information recorded on an optical disc; A second step of moving the optical pickup by the determined predetermined distance; Calculating a track movement amount of the optical pickup; And a fourth step of calculating and storing the width of the single track based on the calculated track movement amount, so that the width of the single track of the optical disk can be accurately and accurately corrected regardless of the size of the data recorded on the optical disk. By calculating, the access time of the optical disk is made the same without being affected by the manufacturing conditions or the density of the optical disk, and in particular, it is a very useful invention that the access time can be shortened in the case of an optical disk having a track width outside the standard.

Description

Track width calculation method of optical disc

The present invention relates to a track width calculation method of an optical disk for detecting a track width of an optical disk. More particularly, the present invention relates to a track width calculation method of an optical disk. Determining a predetermined position to move the optical pickup in the area, moving the optical pickup to the determined predetermined position, calculates the number of tracks corresponding to the traveled distance to detect one track width, and then to the target track in the future By calculating the movement distance, it is possible to calculate the width of a single track accurately regardless of the size of data recorded on the optical disk, and calculate the track width of the optical disk to make the access time of the optical disk the same regardless of the track width of the optical disk. It is about a method.

The configuration of an optical disk drive / detector for driving an optical disk and detecting a signal in a general optical disk player, as shown in FIG. 1, includes a pickup unit for reading a recording signal by injecting a light source into the optical disk 10 ( 11); A sled motor 12a for moving the pickup 11 in the radial direction of the optical disk; A spindle motor 12b for rotating the optical disc 10; A drive unit 30 for driving the sled motor 12a and the spindle motor 12b; An R / F unit 20 for filtering the signal detected by the pickup unit 11; The driving of the drive unit 30 is controlled from the focus error (FE) and tracking error (TE) signals output from the pickup unit 11, and the rotational speed of the optical disc, and the R / F unit 20 A servo unit 40 for detecting synchronization of an output signal of the controller; A digital signal processor (50) for recovering a signal read by the R / F unit (20) to an original digital signal using the detected synchronization; And a microcomputer 60 which moves the pickup section 11 and controls the reproducing operation.

The recording signal detection process in the optical disk driving / detecting unit configured as described above detects the signal recorded on the optical disk 10 continuously while the pickup section 11 is moved in accordance with the reproduction of the optical disk 10. The R / F unit 20 filters the high frequency signal detected by the pickup unit 11. Synchronization is detected by the servo unit 40 and the digital signal processing unit 50 is detected by the R / F unit 20 by the synchronization detected by the servo unit 40. The high frequency signal is restored to original digital data and output as moving picture data.

Subsequently, when the user requests a search mode (search mode), that is, a track of a different position from the track on which the pickup unit 11 is currently located, to the microcomputer 60, the microcomputer 60 performs the digital operation. Current position information of the pickup unit 11 in digital data, which is reproduction control information input from the signal processing unit 50 (position information when the optical disc 10 is a CD is M (minutes) S (seconds) B (Block) data, and the position information when the optical disc 10 is a DVD is a sector number) to calculate a track number corresponding to the detected position information.

When the track number of the target position track to be reproduced is calculated, the difference with the track number of the current position is calculated to determine the number of tracks to be moved and the direction of movement.

When the direction of movement and the number of tracks to be moved are calculated as described above, the microcomputer 60 multiplies the calculated number of tracks by the width of the standard track, and the distance to the target position to which the pickup unit 11 should move. Will yield. When the distance to which the pickup unit 11 is to be calculated is calculated, the microcomputer 60 controls the drive unit 30 through the servo unit 40 so that the pickup unit 11 has the calculated distance. The driving current to be moved is output to the sled motor 12a. Accordingly, the sled motor 12a is rotated by a current applied time to move the pickup 11 in a desired direction.

After the pick-up unit 11 is moved by the target moving distance by the rotational drive of the sled motor 12a, the track information is read from the moved position to check whether the requested data exists in the target track. In this case, a fine search process of re-reading the track information at the moved position is performed by moving the pickup unit 11 to some extent, and thus the movement to the target track is completed.

However, although the track width calculation method of the conventional optical disk made as described above has one track width of the optical disk standardized to 1.6 µm, the track width is not constant due to the optical disk production conditions or the higher density of data. Nevertheless (the standard allowable range of the actual track width is 1.5 to 1.7 µm, and the track of the optical disk is formed within this range), the track width of the optical disk is 1.6 1.6 m unconditionally when calculating the moving distance of the pickup on the optical disk. In order to calculate the moving distance, when the pickup is moved to the target position on an optical disc with a track width of 1.6 μm or less, the pickup passes the target position, and the target position on an optical disc with a track width of 1.6 μm or more. In order to reach the target track accurately, the finer search time is 150 ~ 200msec (2 ~ 3 seconds in severe cases). There is a problem that the access time of the desired data is long.

In order to solve this problem, a new device for determining a moving distance and a determination method of an optical pickup has been proposed and filed by the same applicant as the patent application No. 97-63608.

However, in the above-described filed moving distance determining device and method of optical pickup, the predetermined position is fixed at an arbitrary position on the optical disc in the process of moving the optical pickup to a predetermined position in order to calculate the width of the single track. In the case where the inserted optical disc does not have much record information, such as a game optical disc, as shown in Fig. 2, the fixed predetermined position P may be a point where no data is recorded on the optical disc. There is a problem in that track information on an optical disc cannot be obtained, and thus a process of calculating track width and determining a moving distance cannot be performed.

Accordingly, the present invention has been made to solve the above problems, and the track width calculation method of the optical disk can accurately calculate the track width of the optical disk irrespective of the magnitude of the recording data of the inserted optical disk. The purpose is to provide.

Fig. 1 shows the configuration of a drive / detection unit of a general optical disc player.

Fig. 2 shows a case where the predetermined position P to which the optical pickup is to be moved is located in the non-data recording area on the optical disc.

3 is a block diagram of a drive / detection unit of the optical disc player for implementing the track width calculation method of the optical disc according to the present invention;

4 is a flowchart showing the flow of an embodiment of the track width calculation method of the optical disc according to the present invention;

Fig. 5 shows the data format of playlist information (TOC information) recorded in the Lead-In area on the optical disc.

6 is another configuration diagram of a drive / detection unit of the optical disk player for implementing the track width calculation method of the optical disk according to the present invention;

7 is a flow chart showing the flow of another embodiment of the track width calculating method of the optical disc according to the present invention.

※ Explanation of code for main part of drawing

10 optical disc 11 pick-up part

12a: sled motor 12b: spindle motor

20: R / F part 21: traverse counter

30: drive part 40: servo part

50: digital signal processor 60: microcomputer

70: memory

In accordance with another aspect of the present invention, there is provided a track width calculation method of an optical disc, comprising: a first step of determining a predetermined distance to which an optical pickup is to be moved from playlist information recorded on the optical disc; A second step of moving the optical pickup by the determined predetermined distance; Calculating a track movement amount of the optical pickup; And a fourth step of calculating and storing the width of the single track based on the calculated track movement amount.

In the method for calculating the track width of the optical disc according to the present invention as described above, when the optical disc is first inserted, the playlist information recorded on the inserted optical disc is read to determine the size of the recording data, and from this, the optical disc is read. The predetermined distance in the data recording area to which the pickup will move is determined. When the predetermined distance is determined, the optical pickup is moved by the determined predetermined distance. When the movement of the optical pickup is completed, the actual track movement amount of the optical pickup is calculated, and the single track is based on the calculated track movement amount. By calculating and storing the width of the optical disc, the moving distance of the optical pickup is determined on the basis of the width of the operationally stored single track in the optical disk search request.

Hereinafter, a track width calculation method of an optical disk according to the present invention will be described in detail with reference to the accompanying drawings.

The optical disc player of FIG. 3 for implementing the track width calculation method of the optical disc according to the present invention further includes a memory 70 for storing playlist information on the optical disc in the configuration of FIG. The motor 12a is configured as a step motor so that it can be moved exactly by a desired moving distance, and the drive unit 30 is also configured with a pulse driving circuit suitable thereto.

FIG. 4 is a flow chart showing the flow of an embodiment of the track width calculation method of the optical disc according to the present invention. Hereinafter, the track width calculation method of FIG. 4 will be described with reference to the configuration of FIG. This will be described in detail.

In the method for calculating the track width of the optical disc according to the present invention, when the optical disc 10 is first inserted (S11), the microcomputer 60 controls the pickup unit 11 to track 0 and the optical disc 10. The playlist information (TOC information) recorded in track 1 (Lead-In) is read out. The playlist information includes the total number of points (POINT) and the playing time of each song (MIN, SEC, FRAME) as shown in FIG. ), Information about the absolute start time (PMIN, PSEC, PFRAME), etc. of each song is recorded, and the information is read out by the pickup section 11. The high frequency signal read out from the pickup section 11 is filtered by the RF section 20, and the filtered clean signal is detected by the servo section 40, and the digital signal processing section ( The original digital data is restored by the detected synchronization at 50).

The microcomputer 60 stores playlist information of tracks 0 and 1 of the optical disk 10 restored by the digital signal processor 50 in the memory 70 (S11), and stores the playlist information. By checking the recording data area on the inserted optical disc 10 (S12) to determine the size of the recording data, which is from the start absolute time (PMIN, PSEC, PFRAME) information of each song in the stored playlist information Since the total reproduction time of the data recorded on the optical disc 10 can be known, the recording data can be obtained by identifying the total number of physical tracks on the optical disc 10 corresponding to the total reproduction time of the optical disc 10. The size of the will be judged.

When the size of the recording data is determined as described above, the microcomputer 60 determines the predetermined distance to which the pickup unit 11 moves (S13). For example, the predetermined distance is determined at the initial position. The moving distance is determined such that the distance to the point of approximately 9/10 of the data recording physical track of the optical disc 10 is the inner circumference of the point where data was last recorded on the optical disc 10. When the predetermined distance to which the pickup unit 11 is to be determined is determined, the microcomputer 60 moves from the current initial position at which the pickup unit 11 reads the playlist information by the determined predetermined distance (S14). By applying a predetermined number of pulses through the servo unit 40 and the drive unit 30, the sled motor 12a composed of the step motor is driven.

As the sled motor 12a is driven, the pick-up unit 11 is accurately moved by a predetermined distance and reads track information recorded on the optical disc 10 at the moved position (S15). As described above, the detected signal is digital data which is reproduction control information (sub-Q field) through the R / F unit 20, the servo unit 40, and the digital signal processing unit 50. 60). The microcomputer 60 detects track information MSB at the position where the pickup unit 11 is moved from the reproduction control information input, calculates an actual track number corresponding to the track information MSB, and based on the calculated track number. The number of tracks between the position where the pickup unit 11 is moved and the initial position (track 0 or 1) is calculated (S16).

When the number of tracks is calculated, the microcomputer 60 calculates the width of the single track by dividing the calculated number of tracks by the actual moving distance (distance corresponding to the driving pulse of the step motor) to the predetermined position of the pickup unit 11. After obtaining (S17), it is stored itself (S18).

Subsequently, during the sequential playback of the optical disc 10 (S19), when the search mode is input to the microcomputer 60 (S20), track information to be moved from the playback control information read and stored in the memory 70 is checked. (S21), after obtaining a track number corresponding to the checked track information MSB, calculating the difference with the track currently being reproduced, and calculating the number of tracks to be moved by the pickup unit 11 (S22). By multiplying the calculated number of tracks by the width of the single track calculated and stored in the previous step, the moving distance from the optical disk to the target position to which the pickup unit 11 should move is determined (S23).

When the movement distance is determined as described above, the microcomputer 60 drives the sled motor 12a by the driving pulse of the drive unit 30 as described above to drive the pick-up unit 11 to the expected target track. After moving to (S24), it will be moved to the target track by the fine search process.

FIG. 6 is another configuration diagram of a drive / detection unit of the optical disk player for implementing the track width calculation method of the optical disk according to the present invention, which is read-in and input by the pickup unit 11 in the above-described configuration of FIG. A traverse counter 21 for detecting a traverse signal from the signal and counting the number is further included.

In the track width calculation method of the optical disk according to the present invention of FIG. 7 made up from the configuration of FIG. S14), and only after the pickup 11 is moved to a predetermined position, the number of tracks between the moved position and the initial position is calculated from the track information on the optical disc 10 at the moved position. Rather, the traverse counter 21 counts the number of traverse signals from the signal inputted as read by the predetermined distance of the pickup unit 11 (S45), so that the traverse track information up to the moved position is counted. The traverse signal is a signal that is detected while the pickup 11 traverses a mirror surface existing between the track and the track, so that the pickup 11 is moved from an initial position to a predetermined position. E.g In the case of crossing 1000 tracks, the number of traverse signals counted from the traverse counter 21 is generally 999. As a result, the microcomputer 60 recognizes that the number of tracks is 1000 during the predetermined distance movement of the pickup unit 11, and the subsequent process is performed in the same manner as in the above-described embodiment.

In the above embodiment, the sled motor 12a is used instead of the step motor, and the sled motor 12a for moving the pickup 11 by the predetermined distance is used. When driving, unlike the step motor, since the rotation amount by the drive is not accurate, the Hall sensor (not shown) detects the rotation amount of the actual DC motor rotation, and a counter (not shown) is outputted according to the rotation. By counting and transmitting the calculated value to the microcomputer 60, the microcomputer 60 checks the distance to be moved, and when the pickup unit 11 is moved by a predetermined movement distance, driving through the drive unit 30 is performed. The subsequent track width calculation is performed in the same manner as in the above-described process.

In the track width calculation method of the optical disk according to the present invention made as described above, it is possible to accurately calculate the width of a single track of the optical disk irrespective of the magnitude of the data size recorded on the optical disk, thereby producing the optical disk. Alternatively, the access time of the optical disk is the same without being affected by the density, and in the case of an optical disk having a track width outside the standard, it is a very useful invention that can shorten the access time.

Claims (2)

A first step of determining a predetermined distance to which the optical pickup will move from the playlist information recorded on the optical disc; A second step of moving the optical pickup by the determined predetermined distance; Calculating a track movement amount of the optical pickup; And And a fourth step of calculating and storing the width of the single track based on the calculated track movement amount. The method of claim 1, And a fifth step of determining a moving distance of the optical pickup based on the width of the operation-stored single track when the optical disc search request is made.