KR19980030556A - Apparatus and method for compensating disc deviation of an optical disc player - Google Patents

Abstract

The present invention relates to a disc deviation compensating apparatus and method for an optical disc player, comprising: an optical pickup unit for converting an optical signal picked up by performing an optical pickup from a disc (D) into an electrical signal and outputting an RF (radio frequency) signal ( 10) and a focus error detector 20 for detecting and outputting a focus error signal, and a compensator 30 for outputting a compensation signal for focusing in the optical pickup unit 10 according to the focus error signal. The pickup driving unit 40 for driving the optical pickup unit 10 to compare the focus error signal with a preset reference signal to obtain a deviation signal, and compare the deviation signal with a preset reference deviation signal to control the signal accordingly. The pick-up base 12 constituting the optical pick-up section 10 according to the deviation control unit 50 and the control signal provided from the deviation control unit 50 to generate a vertical direction. The drive is configured by including a pickup base and driver 60 to compensate for the deviation due to deformation of the disk.

Therefore, the present invention has an effect of smoothly performing the focus servo by compensating for the deviation caused by the deformation of the disk.

Description

Disc deviation compensation device and method for optical disc player

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc player, and more particularly, to a disc of an optical disc player that compensates for a disc deviation caused by the disc bending upward or downward due to disturbance or internal error when playing a predetermined disc in the optical disc player It relates to a deviation compensation device and method.

With the development of audio and video media, optical disc players for recording and reproducing video and audio data on semi-permanent optical discs have been developed.

Such an optical disc player is characterized by a digital recording method and a non-contact reproducing method. In particular, the optical disc player performs non-contact reproduction of a recording bit signal engraved on the optical disc by light and thereby performs digital signal processing. In other words, it is well known that optical disc players bring improved performance that is difficult to realize in analog recording / reproducing systems, as well as operability such as random access or program reproduction utilizing non-contact playback.

In addition, such an optical disc player reproduces an image and / or sound recorded on an optical disc and outputs it through a screen and / or a speaker, and has a higher signal-to-noise ratio than conventional image and / or audio reproducing apparatus, resulting in better image quality. And / or can reproduce signals with sound quality, generate no noise due to irregular reproduction and modulation, have very little distortion, no ghosts, and random access. There is a trend that is spreading.

In addition, such an optical disk player includes a compact disk player (CDP), a laser disk player (LDP), a compact disk graphic player (CDGP), and a video compact disk player (VCDP: video compact disk player) has been developed and widely used. Also, recently, a digital video disk (DVD) using MPEG-2 moving picture compression technology and a digital video disk player for playing the same have been developed. It can record and play back gigabytes (GB) of data including moving images on a 12cm optical disc such as a CD, and it is also designed to be compatible to play current CDs and VCDs.

On the other hand, in such an optical disc player, optical is used to read data as described above. In order to read data recorded accurately on the optical disc, it is necessary to precisely focus the light on the data surface recorded on the optical disc. That is, it is necessary to follow the focus of the light according to the surface vibration according to the rotation of the optical disk, that is, the vertical movement of the disk.

Therefore, in such an optical disc reproducing apparatus, a focus servo apparatus is adopted to focus the light irrespective of the vertical vibration of the optical disc, which focuses the optical disc used to read data recorded on the optical disc surface. A main unit is an apparatus for accurately reading data recorded on an optical disk by moving an optical pickup unit, that is, an objective lens, up and down according to the movement of the optical disk to focus the light accurately on the surface of the optical disk.

That is, as shown in FIG. 1, the pickup member 14 coupled to the pickup base 12 and mounted thereon with a pickup actuator moves upward or downward to allow pickup of light from the disk D. FIG. .

By the way, when playing a predetermined disc in the optical disc player, a focus error such that focusing cannot be performed by the focus servo as described above may occur.

That is, as shown in FIG. 2, the disk is bent or deformed by a distance Δx such that the pickup member 14 moves up and down in the up or down direction due to disturbance or an internal defect so that focusing cannot be performed. In this case, there is a problem in that the focus servo is not made and a change in the RF (raio frequency) signal level that is reproduced may affect reproduction performance.

Therefore, the present invention has been proposed to solve the above-mentioned conventional problems, and an object of the present invention is to compensate for the disc when the disc is bent or deformed due to disturbance or internal defects during playback, thereby making it possible to compensate for this. The present invention provides a device and method for compensating deviation of a player.

According to a preferred embodiment of the present invention for achieving this object, the present invention provides a disc of an optical disc player for compensating for deviations caused by deformation of a disc caused by disturbance or internal defects when performing playback in an optical disc player. An optical pickup unit comprising: a pickup base, a pickup member, and a pickup actuator, the optical pickup unit configured to perform optical pickup from a disk to convert an optical signal picked up into an electrical signal and output a radio frequency (RF) signal; A focus error detector for detecting and outputting a focus error from the RF signal provided from a pickup unit, a compensator for outputting a compensation signal for focusing according to a focus error signal provided from the focus error detector, and the compensation Driven according to the compensation signal provided from the The pickup driver for focusing the light pickup unit and the focus error signal provided from the focus error detector are compared with a preset reference signal to obtain a deviation signal, and the deviation signal is compared with a preset reference deviation signal. And a pickup base driver for compensating for deviations caused by deformation of the disk by driving the pickup base constituting the optical pickup unit in the up or down direction according to the deviation control unit generating a control signal according to the control signal provided from the deviation control unit. It includes.

According to another preferred embodiment of the present invention for achieving this object, by driving the pickup base constituting the optical pickup unit, the deviation caused by the deformation of the disk caused by the disturbance or the internal defect when the playback is performed in the optical disc player is performed. A disc deviation compensation method of an optical disc player for compensating, comprising the steps of: (a) detecting a focus error caused by executing a focus servo; and (b) presetting a focus error signal detected in the step (a). Detecting the deviation signal in comparison with a reference signal; and (c) comparing the deviation signal detected in the step (b) with a preset reference deviation signal to determine whether the detected deviation signal is outside the control range of the focus servo. And (d) detecting the deviation signal in the step (c). If outside the control range, driving the pickup base in an upward or downward direction to compensate for the deviation caused by the detected deviation signal.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 schematically shows a disc and an optical pickup in an optical disc player.

Fig. 2 is a diagram for explaining the deviation caused by the tilt of the disc in the optical disc player.

Fig. 3 is a block diagram showing a disc deviation compensation device of the optical disc player in the preferred embodiment of the present invention.

4 is a flowchart of a disc deviation compensation method of an optical disc player according to another preferred embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

10: optical pickup section 12: pickup base

14: Pickup member 16: Actuator

20: focus error detection unit 30: compensation unit

40: deviation control unit 60: pickup base drive unit

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

3 is a block diagram of a disc deviation compensator of an optical disc player according to an exemplary embodiment of the present invention.

As shown in FIG. 3, the disc deviation compensating apparatus of the optical disc player according to the present invention comprises a pickup base 12, a pickup member 14, and a pickup actuator 16 to perform optical pickup from the disc D. The optical pickup unit 10 converts the picked optical signal into an electrical signal and outputs the RF signal as a radio frequency (RF) signal, and compares the level of the RF signal provided from the optical pickup unit 10 with a reference RF level. A focus error detector 20 for detecting and outputting a focus error, and a compensator for outputting a compensation signal for focusing in the optical pickup unit 10 according to the focus error signal provided from the focus error detector 20 ( 30 and a pickup driver 40 for driving the optical pickup unit 10 to be focused according to the compensation signal provided from the compensation unit 30 and the focus error detector 20. The deviation control unit 50 and the deviation control unit 50 are provided from the deviation control unit 50 and the deviation control unit 50 to obtain a deviation signal by comparing the signal error signal with a preset reference signal, and generate a control signal according to the deviation signal with a preset reference deviation signal. And a pickup base driver 60 for compensating for variations due to deformation of the disk by driving the pickup base 12 constituting the optical pickup unit 10 in the up or down direction in accordance with a control signal.

The optical pickup section 10 includes a pickup base 12, a pickup member 14, and a pickup actuator 16, which performs optical pickup from the disk D, converts the picked optical signal into an electrical signal, and converts the RF signal into an RF signal. The signal is output to the focus error detector 20 as a radio frequency signal.

In addition, the focus error detection unit 20 compares the static pressure level of the RF signal provided from the optical pickup unit 10 with a reference RF voltage level, detects a focus error according to the difference, and outputs it to the compensation unit 30.

The compensator 30 outputs a compensation signal for focusing in the optical pickup unit 10 to the pickup driver 40 according to the focus error signal provided from the focus error detector 20.

In addition, the pickup driver 40 is driven according to the compensation signal provided from the compensation unit 30 to drive the optical pickup unit 10 in the direction of reducing the focus error so that the optical pickup unit 10 performs focusing. .

Meanwhile, the deviation controller 50 compares the focus error signal provided from the focus error detector 20 with a preset reference signal, obtains a deviation signal corresponding to the difference, and compares the deviation signal with a preset reference deviation signal, eg, For example, when the disc is deformed in the up and down direction, the maximum value of the controllable range, i.e., the maximum value of the focus servo, is out of the range of the maximum control value, that is, the focus control range. In this case, the control signal is provided to the pickup base driver 60.

Accordingly, the pickup base driver 60 drives the pickup base 12 constituting the optical pickup unit 10 in the up or down direction in accordance with a control signal provided from the deviation controller 50 to deform the warpage of the disk. By compensating for the deviation caused by the focus servo smoothly.

4 is a flowchart of a disc deviation compensation method of an optical disc player according to another preferred embodiment of the present invention.

When the focus servo is executed in step S10, a focus error according to the focus servo is detected in step S20.

In operation S30, the focus error signal detected in operation S20 is compared with a preset reference signal to detect the deviation signal, and the operation proceeds to operation S40.

Then, in step S40, the deviation signal detected in step S30 is compared with the preset reference deviation signal to determine whether the deviation signal detected in step S30 is out of the control range of the focus servo. In other words, when the disc is deformed in the up and down directions, the maximum value range in the up and down directions that can be controlled is preset as a reference deviation signal, and this signal is compared with the detected deviation signal to control the focus servo control range. If the deviation value detected in step S40 is not within the range of the preset reference signal, the flow returns, and if so, the flow proceeds to step S50.

If the deviation signal detected in step S40 proceeds to step S50 outside the control range by the focus servo, that is, the range of the preset reference signal, in step S50, the pickup base is detected by driving the pickup base upward or downward. Compensate for deviations caused by deviation signals.

As described above, the present invention has an effect of smoothly performing the focus servo by compensating for the deviation caused by the deformation of the disk.

Claims (2)

In the disc deviation compensating device of an optical disc player for compensating for the deviation caused by the deformation of the disc (D) which occurs due to disturbance or internal defects when performing playback on the optical disc player, A pickup base 12, a pickup member 14, and a pickup actuator 16, which performs optical pickup from the disk D, converts the picked optical signal into an electrical signal and outputs it as an RF (radio frequency) signal. A pickup section 10; A focus error detector 20 for detecting and outputting a focus error from the RF signal provided from the optical pickup unit 10; A compensator (30) for outputting a compensation signal for focusing according to a focus error signal provided from the focus error detector (20); A pickup driver 40 for driving focusing of the optical pickup unit 10 according to a compensation signal provided from the compensation unit 30; Deviation control unit 50 that compares the focus error signal provided from the focus error detection unit 20 with a preset reference signal to obtain a deviation signal, and compares the deviation signal with a preset reference deviation signal to generate a control signal accordingly. )Wow; Compensating for the deviation due to deformation of the disk D by driving the pickup base 12 constituting the optical pickup unit 10 in the up or down direction in accordance with a control signal provided from the deviation controller 50. Disc deviation compensation device of the optical disc player comprising a pickup base drive (60). Optical disc player for compensating for deviations due to deformation of the disc D caused by disturbance or internal defects when the playback is performed in the optical disc player by driving the pickup base 12 constituting the optical pickup section 10. In the disk deviation compensation method of (A) detecting a focus error caused by executing the focus servo; (B) comparing the focus error signal detected in step (a) with a preset reference signal and detecting the deviation signal; (C) comparing the deviation signal detected in step (b) with a preset reference deviation signal to determine whether the detected deviation signal is out of a control servo control range; (D) if the detected deviation signal is out of the control range by the focus servo in step (c), driving the pickup base upward or downward to compensate for the deviation caused by the detected deviation signal; Disk deviation compensation method of an optical disk player.