KR100197630B1 - Multiprocessing method for disc search - Google Patents

Abstract

The disclosed contents relate to a method of recognizing and reproducing a disc according to the diameter and thickness of a CD, a VIDEO-CD, a CD-ROM, an LD and a DVD mounted on an optical disc player In particular, the present invention relates to a method for simultaneous execution of disk search in which each servo system operation from disk loading to reproduction in the ODP is simultaneously operated and disk identification is performed simultaneously.

Therefore, if the simultaneous execution of the disk search according to the present invention is used, the disk search time is shortened and the disk is reproduced within a short time after the disk is mounted.

Description

How to perform disk search concurrently

The present invention relates to a method for concurrently performing disk search in which each servo system operation until the disk is mounted in the ODP and then the disk is recognized simultaneously.

In general, an ODP is an optical pickup that scans a laser beam onto a reflective surface of a disc and reads an information signal embedded in the disc from the reflected beam, and an optical system that moves the optical pickup in a radial direction And a delivery mechanism.

When disks having different diameters are mounted on the ODP having such a configuration, the optical pickup scans the disk from the outermost side of the disk mounting position having the largest diameter, and recognizes the disk through presence or absence of the reflected beam. Without the reflected beam, the optical pickup moves to the second largest diameter disc loading position, scanning the disc again, and recognizing the disc through the presence or absence of the reflected beam. If there is no reflected beam, this process continues until the disc is recognized. After the mounted disc is recognized, the ODP system sequentially operates so that the loaded disc is reproduced. When the disc is loaded in the ODP, the operation is sequentially performed until the disc is reproduced.

The progress of the process will be described with reference to the accompanying drawings.

FIG. 1 is a flowchart illustrating sequential operations until a disc is inserted into a general ODP.

The disc is loaded on the ODP (step 101) and the play button is turned " on " (step 102). When the step 102 is performed, the optical pickup of the ODP moves from the initial position to the position where the outermost part of the disc, that is, the position of the laser disc, can be determined (step 103). Presence or absence of the LD is determined by whether or not the beam scanned on the disk is reflected at that position (step 104). If there is a return beam, that is, a reflected beam, it is determined that the LD is mounted, and the ODP is performed in order from step 109. However, if there is no reflected beam, it is determined that the LD is not mounted, and the optical pickup continues to move to a position where it is possible to determine the presence or absence of a CD (step 105). As in the case of the LD, the presence or absence of the CD is judged by the presence or absence of reflection of the scanned beam at the position (step 106). Here, if there is a reflection of the scanned beam, it is determined that the CD is mounted, and the ODP is performed in order from step 109. However, if there is no reflected beam, it is determined that the CD is not mounted, and the optical pickup is moved to the 8 cm diameter disc existence determination position (step 107). If there is no reflection of the scanned beam on the disk at this location, then there is no disk mounted on this ODP and the disk seeking process is terminated (this step is not shown). However, since there is an initial disk mounting in this ODP, there is a reflection of the scanned beam at the position of 8 cm diameter disk determination. Thus, it is confirmed that there is an 8 cm diameter disc at this position, and the disc is recognized (step 108). After the type of the disk mounted on the ODP is sequentially discriminated and recognized, the operation of the servo system for reproducing the disk is sequentially performed. That is, a focus servo is operated to adjust the position of the lens in the optical pickup such that the beam reflection surface of the mounted disk is within the depth of focus (Step 109). After step 109, a spindle servo for locking the spindle motor is operated in step 110 so that the spindle motor rotates at a predetermined rotation speed and rotates the mounted disk at a predetermined speed. After the step 110 is performed, a track of the loaded disc is accurately tracked and a tracking servo is operated to cause the beam to be accurately scanned even if the disc vibrates (step 111). After the servo system operates as described above, the optical pickup is moved to the lead-in position of the recognized disc (step 112). The information embedded in the disc at the lead-in position is read-in, and the recognized disc is reproduced (Step 113).

As described above, when a disc is loaded in the ODP, the optical disc is recognized while the presence or absence of the disc is checked by moving the optical pickup. After the disc is recognized, focus servo = spindle servo = tracking servo operates. After the servo system operates, the disc is read-in and reproduced.

In general, since the disc is played through the sequential operation of the ODP, the search time until the disc is loaded after the disc is loaded, that is, a predetermined position is read from the arbitrary point of the disc and the signal at that position is read, There is a problem that it takes a lot of time.

Particularly, the search time is a crucial factor when converting to 4x, 8x, and 12x speeds like CD-ROM. Therefore, a method for reducing the search time is sought.

1 is a flowchart showing a sequential method of disk search,

FIG. 2 is a flowchart illustrating a method for simultaneously performing a disk search according to the present invention. FIG.

A feature of the present invention for reducing the search time is that after each disk is mounted, each of the servo systems operates simultaneously, and an operation of discriminating the type of disk mounted at the same time is performed, thereby recognizing the disk once.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 2 is a flow chart for explaining a simultaneous operation until the disc is inserted into the ODP.

The disc is loaded in the ODP (step 201) and the play button is turned " on " (step 202). When the step 202 is performed, the optical pickup is moved from the initial position to the disc lead-in position when the disc is loaded (step 203). Further, the focus tracking spindle servo operates simultaneously while the optical pickup is moved from the arbitrary initial position to the disc lead-in position. A process of discriminating the type of the mounted disk at the same time as each of the servo system operations is performed. That is, the type of the mounted disk is discriminated during the operation of the focus servo, and the type of the mounted disk is discriminated during the operation of the tracking servo. At the same time, the type of the loaded disk is determined during the operation of the spindle servo. In this manner, discrimination of the disk mounted simultaneously with the servo system operation is performed, and discrimination information generated is determined in total, and the mounted disk is recognized once (Step 204). After step 204, a check is made to see if the optical pickup has been moved to the lead-in position of the recognized disc. If there is an error, the optical pickup is moved again (step 205). After step 205 is correctly performed, the loaded disc is read-in and reproduced (step 206).

Hereinafter, how the simultaneous operation of each servo system simultaneous operation and the disk type discrimination performed during the operation of step 203, that is, while the optical pickup is moved, will be described in more detail.

The focus servo operation is performed in step 203, and the mounted disk is scanned with a beam and the output level of the reflected beam varies depending on the disk thickness. For example, a CD has a thickness of 1.2 mm and a DVD has a thickness of 0.6 mm, and the reflection output level of the CD is about one third of the DVD. Thus, the loaded disc is discriminated as CD, VCD, LD if the level of the sensed reflection output is LOW, and DVD if the level is high. In step 203, a tracking servo operation is performed, and a brightness level of the reflected beam output corresponding to the presence or absence of the mounted disk pit is sensed to count the disk tracks. Thus, when the disc track count is low, the disc mounted during an arbitrary time is discriminated as CD, VCD, LD having a track pitch of 1.6 mu m, and when the disc track count is high, a DVD having a track pitch of 0.74 mu m .

In step 203, the spindle servo operation is performed, and the number of disk rotations corresponding to the mounted disk diameter is counted. Thus, the mounted disc is discriminated as an LD having a diameter of 30 cm when the counted number of disc rotations is low, a CD, VCD, DVD having a diameter of 12 cm, and a disc having a diameter of 8 cm when the middle is high. After the disc type is determined, the spindle motor voltage is adjusted so as to match each disc determined, and the spindle motor is spinned so that it can rotate at a predetermined number of revolutions.

The type discrimination information for the mounted disk, which is performed together with the simultaneous operation of the servo system, is comprehensively determined, and the mounted disk is recognized once in step 204. [ Through this process, the mounted disc is recognized.

In addition, Table 1 below summarizes the type discrimination method for the disk loaded in step 203 described above.

Beam reflection output level Track count Disk rpm LOW HIGH LOW HIGH LOW MIDDLE HIGH CD, VCD, LD DVD CD, VCD, LD DVD LD CD, VCD, DVD Diameter 8 cm disk

As described above, the loaded disc is identified as CD, VCD, LD if the reflection output level of the beam is low, and DVD if it is high. If the track count is low, it is discriminated as CD, VCD, LD. Further, the mounted disc is discriminated as LD if the number of rotations of the disc is low, CD, VCD, DVD if it is middle, and 8 cm disc if it is high.

As described above, when the disc is loaded in the search operation until the disc is loaded after the disc is loaded according to the present invention, the focus tracking spindle servo operates simultaneously as the optical pickup is moved to the continuous lead-in position. In addition, the type discrimination for the disk loaded with each servo system operation is performed, and the discrimination information generated while discriminating the type is judged in total, and the mounted disk is finally recognized.

As described above, in the simultaneous execution of disk search according to the present invention, the type of the mounted disk is simultaneously performed while the simultaneous operation of each servo system is performed, and the mounted disk is recognized through the discrimination information obtained at one time.

Accordingly, such a simultaneous execution method has the advantage that the search time until the disc is reproduced is shortened, and the disc is reproduced within a short time after the disc is mounted.

Claims (4)

A method of performing a search process of a disk mounted on an optical disk player, (1) performing a discriminating operation on the type of the mounted disk while the servo systems operate simultaneously; And (2) performing a disc discrimination operation on the type of disc in the first step, and recognizing the disc type discrimination information generated one time, and recognizing the loaded disc one time. The method as claimed in claim 1, wherein the first and second steps are performed while the optical pickup is moved from an initial position at the time of mounting the disc to a lead-in position at which the disc is recognized. 2. The method of claim 1, wherein the servo systems of the first stage are partially activated at the same time. The method according to claim 1, wherein the disc type discrimination information in the second step is generated according to a diameter and a thickness of a mounted disc and a track interval.