KR100595502B1 - Sensing and compensating method for twist of disc - Google Patents

Sensing and compensating method for twist of disc Download PDF

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Publication number
KR100595502B1
KR100595502B1 KR1019990060915A KR19990060915A KR100595502B1 KR 100595502 B1 KR100595502 B1 KR 100595502B1 KR 1019990060915 A KR1019990060915 A KR 1019990060915A KR 19990060915 A KR19990060915 A KR 19990060915A KR 100595502 B1 KR100595502 B1 KR 100595502B1
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South Korea
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disk
high frequency
frequency signal
driving voltage
focusing
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KR1019990060915A
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Korean (ko)
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KR20010057473A (en
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허삼성
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엘지전자 주식회사
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    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
    • G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
    • G11B7/095—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following specially adapted for discs, e.g. for compensation of eccentricity or wobble
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
    • G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
    • G11B7/0908—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following for focusing only
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
    • G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
    • G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
    • G11B7/0941—Methods and circuits for servo gain or phase compensation during operation

Abstract

본 발명은 디스크의 면진 판단 및 보상 방법에 관한 것으로, 종래 기술에 있어서 로딩된 디스크를 재생시 동일한 이상 현상을 보이면 면진 디스크인지에 대한 구분할 방법이 없어 기록 및 재생 특성이 나쁘며, 이에 동일한 필터이득값으로 필터링시 면진 디스크의 경우 데이터를 기록한 후 이를 재생시 내주와 외주의 포커싱에서 신호 성분에 큰 차이가 발생함으로써, 제어 대역이 높아 노이즈의 발생이 심한 문제점이 있었다. 따라서, 본 발명은 상기와 같은 종래의 문제점을 해결하기 위하여 창안한 것으로, 디스크의 내주와 외주를 동일한 포커스 구동 전압으로 포커싱시 출력되는 고주파 신호의 진폭 변화량에 따라 면진 디스크인지의 여부을 판단하여 면진 디스크이면 내주와 외주의 필터이득값을 서로 다르게 설정하여 면진을 보상함으로써, 노이즈의 발생을 최소화하여 기록 및 재생 특성을 향상시키는 효과가 있다.The present invention relates to a disk isolation determination and compensation method, and in the prior art, if there is an abnormality when playing a loaded disk, there is no method of distinguishing whether the disk is a isolation disk, and the recording and reproduction characteristics are poor. In the case of filtering the filter, when the data is recorded, a large difference occurs in the signal components in the focusing of the inner and outer circumferences when the data is recorded and then reproduced. Accordingly, the present invention has been devised to solve the above-mentioned conventional problems, and it is judged whether or not the base isolation disk according to the amplitude change amount of the high frequency signal outputted when focusing the inner and outer circumference of the disc with the same focus driving voltage. By setting the filter gain values of the inner and outer circumferences differently, the rear face compensation is compensated for, thereby minimizing the occurrence of noise and improving recording and reproduction characteristics.

Description

디스크의 면진 판단 및 보상 방법{SENSING AND COMPENSATING METHOD FOR TWIST OF DISC}SENSING AND COMPENSATING METHOD FOR TWIST OF DISC}

도 1은 본 발명 면진 디스크 판단 동작을 보인 흐름도.1 is a flow chart showing the operation of the present invention isolating disk determination.

도 2는 도 1에서 면진 디스크에서 내주와 외주의 시간에 따른 포커스 구동 전압, 포커스 에러 전압 및 고주파 신호를 보인 도.FIG. 2 is a view illustrating a focus driving voltage, a focus error voltage, and a high frequency signal according to time of the inner and outer circumferences of the isolation disk in FIG.

도 3은 본 발명 면진 디스크 보상 동작을 보인 흐름도.3 is a flow chart showing the present invention isolation disk compensation operation.

도 4는 도 3에서 면진 디스크에서 내주와 외주에 따른 필터이득값의 관계를 보인 도.4 is a view showing the relationship between the filter gain value according to the inner circumference and the outer circumference in the base isolation disk in FIG.

본 발명은 디스크의 면진 판단 및 보상 방법에 관한 것으로, 특히 디스크의 면진을 판단하여 보상함에 있어서 디스크의 내주와 외주의 고주파 신호의 진폭 변화량을 통해 면진 디스크 여부를 판단하여 서로 다른 필터이득값으로 이를 보상하도록 한 디스크의 면진 판단 및 보상 방법에 관한 것이다.The present invention relates to a disk isolation judgment and compensation method, and in particular, in determining and compensating the disk isolation, it is determined whether the disk is isolated through the amplitude variation of the high frequency signals of the inner and outer disks of the disk, and the filter gain value is determined by different filter gain values. The present invention relates to the determination of the base isolation and the compensation method of a disk.

일반적으로 로딩되는 디스크가 외주와 내주의 높이차가 없는 정상적인 디스크의 경우, 내주에서 초점이 맞춰진 포커싱 구동 전압을 이용하여 내주와 외주를 포커싱하여도 각각 포커스 에러 전압이 거의 발생하지 않는다.In general, in the case of a normal disk in which the loaded disc does not have a height difference between the outer circumference and the inner circumference, the focus error voltage hardly occurs even when the inner and outer circumferences are focused using the focusing driving voltage focused on the inner circumference.

그러나, 상기 외주와 내주의 높이차가 있는 면진 디스크의 경우, 상기 내주에서 초점이 맞춰진 포커싱 구동 전압을 이용하여 상기 내주의 포커싱 구동 전압으로 포커싱후, 동일한 포커싱 구동 전압으로 외주에서 포커싱시 포커스 에러 전압이 발생하게 된다.However, in the case of a base isolation disk having a height difference between the outer circumference and the inner circumference, the focus error voltage when focusing at the outer circumference with the same focusing driving voltage after focusing with the focusing driving voltage of the inner circumference using the focusing driving voltage focused on the inner circumference. Will occur.

이에 이를 재생하여 상기 포커스 에러 문제가 발생하는 경우, 포커스 서보를 설계시 하나의 디스크에 대해서 내외주에 관계없이 에러가 가장 클 때의 경우에 대비하여 설정된 필터이득값을 이용하여 보상하였다.When the focus error problem occurs by reproducing it, the design of the focus servo is compensated by using the set filter gain value in case of the largest error regardless of the inner and outer circumferences of the focus servo.

그러나, 상기와 같이 종래의 기술에 있어서 로딩된 디스크를 재생시 동일한 이상 현상을 보이면 면진 디스크인지에 대한 구분할 방법이 없어 기록 및 재생 특성이 나쁘며, 이에 동일한 필터이득값으로 필터링시 면진 디스크의 경우 데이터를 기록한 후 이를 재생시 내주와 외주의 포커싱에서 신호 성분에 큰 차이가 발생함으로써, 제어 대역이 높아 노이즈의 발생이 심한 문제점이 있었다.However, in the related art, when the loaded disc shows the same abnormal phenomenon when playing the loaded disc, there is no method of distinguishing whether the disc is a disc isolated and the recording and reproduction characteristics are poor. After recording the audio signal, a large difference occurs in the signal components in the focusing of the inner and outer circumferences during the playback.

따라서, 본 발명은 상기와 같은 종래의 문제점을 해결하기 위하여 창안한 것으로, 디스크의 내주와 외주의 고주파 신호의 진폭 변화량을 통해 면진 디스크인지의 여부를 판단하여 외주를 내주의 필터이득값보다 큰 필터이득값으로 보상하도록 한 디스크의 면진 판단 및 보상 방법을 제공함에 그 목적이 있다.Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and it is determined whether the disk is an isolated base by the amplitude change amount of the high frequency signal of the inner and outer circumferences of the disk, and the outer circumference is larger than the filter gain value of the inner circumference. It is an object of the present invention to provide a method for judging and isolating a disk to compensate with a gain value.

상기와 같은 목적을 달성하기 위한 본 발명은 디스크의 내주에서 포커스 온되는 포커스 구동 전압을 검출한 뒤, 그 전압으로 포커싱시의 고주파 신호를 검출하는 제1 단계와; 상기 제1 단계의 동작이 완료되면, 디스크의 외주로 이동하여 상기 검출된 포커스 구동 전압으로 포커싱하며, 그 때의 고주파 신호를 검출하는 제2 단계와; 상기 제2 단계의 동작이 완료되면, 상기 디스크의 외주와 내주에서 검출된 고주파 신호의 진폭 변화량에 의해 면진 디스크인지의 여부를 판단하는 제3 단계로 이루어진 것을 특징으로 한다.The present invention for achieving the above object is a first step of detecting a focus driving voltage focused on the inner circumference of the disk, and then detecting a high frequency signal at the time of focusing with the voltage; A second step of moving to the outer periphery of the disk to focus on the detected focus driving voltage when the operation of the first step is completed, and detecting a high frequency signal at that time; When the operation of the second step is completed, it is characterized in that it comprises a third step of determining whether or not the base isolation disk by the amplitude change amount of the high frequency signal detected in the outer and inner circumference of the disk.

그리고, 본 발명은 면진 디스크인지 판단하여 아니면 내주와 외주의 필터이득값을 동일하게 설정후 종료하고, 면진 디스크이면 내주의 필터이득값보다 외주의 필터이득값을 높게 설정후 종료하는 단계로 이루어진 것을 특징으로 한다.Then, the present invention is to determine whether or not the base of the outer filter and the outer peripheral filter gain value is set to the same, if the base disk is set to the filter gain value of the outer peripheral than the filter gain value of the inner peripheral end of the step consisting of It features.

이하, 본 발명에 따른 일실시예에 대한 동작과 작용효과를 첨부한 도 1 내지 도 4를 참조하여 상세히 설명하면 다음과 같다.Hereinafter, with reference to Figures 1 to 4 attached to the operation and effect for one embodiment according to the present invention will be described in detail.

우선, 도 2의 (a)와 같은 면진 디스크가 로딩된 경우, 상기 디스크가 면진 디스크인지 판단하기 위하여 상기 디스크의 내주에서 포커스 구동 전압을 도 2의 (b)와 같이 인가하면, 그때의 포커스 에러 전압이 도 2의 (c)와 같이 0가 되는 지점에서의 포커스 구동 전압을 검출한 뒤, 상기 포커스 구동 전압으로 포커싱하여 그 때의 고주파 신호를 검출한다.(S1)First, when the isolating disk as shown in FIG. 2 (a) is loaded, if a focus driving voltage is applied as shown in FIG. After detecting the focus driving voltage at the point where the voltage becomes zero as shown in FIG. 2C, the focus driving voltage is detected and the high frequency signal is detected at that time (S1).

그리고, 상기 디스크의 외주로 이동하여 도 2의 (d)와 같이 검출된 상기 포커스 구동 전압을 포커싱하여 그때의 고주파 신호를 도 2의 (e)와 같이 검출한다.(S2)Then, it moves to the outer periphery of the disk, focuses the focus driving voltage detected as shown in FIG. 2 (d), and detects the high frequency signal at that time as shown in FIG.

그리고, 상기 디스크상 내주의 고주파 신호와 외주의 고주파 신호의 진폭 변화를 통해 외주 고주파 신호의 진폭변화가 내주 고주파 신호의 진폭변화보다 30%이상 차가 있는지 판단한다.(S3)Then, it is determined whether the amplitude change of the outer high frequency signal is 30% or more different from the amplitude change of the inner high frequency signal by changing the amplitude of the inner frequency high frequency signal and the outer frequency high frequency signal on the disk (S3).

이때, 상기 진폭변화가 30%이상이면, 상기 로딩된 디스크를 면진 디스크로 판단하고(S4), 30%이하이면 정상적인 디스크로 판단한다.(S5)At this time, if the amplitude change is more than 30%, the loaded disk is determined as an isolating disk (S4), if less than 30% is determined to be a normal disk (S5).

이때, 상기 로딩된 디스크가 도 2의 (a)와 같이 면진 디스크이므로 상기 내주와 외부의 진폭 변화가 30%이상 발생하며, 상기 면진 디스크의 외주가 내주보다 포커스 에러 신호가 도 4와 같이 크므로, 상대적으로 외주의 에러 신호가 내주의 에러 신호보다 크다.In this case, since the loaded disk is an isolating disk as shown in FIG. 2A, the amplitude change of the inner and outer disks is more than 30%, and the outer error of the isolating disk is larger than the inner circumference, so the focus error signal is larger than that of the inner disk. In other words, the error signal of the outer circumference is larger than that of the inner circumference.

따라서, 상기에서 면진 디스크로 판단된 경우에는 도 3의 흐름도에서와 같이, 내주의 필터이득값(filter gain Ⅰ)보다 외주의 필터이득값 (filter gain Ⅱ)을 크게 설정하여 상대적으로 내주의 에러 신호보다 큰 외주의 에러 신호를 효과적으로 제거한다.(S8)(S9)Accordingly, when it is determined that the base isolation disk is the above, as shown in the flowchart of FIG. 3, the outer gain filter gain value (filter gain II) is set larger than the inner filter gain value (filter gain I). Efficiently removes a larger outer error signal (S8) (S9).

그러나, 상기 로딩된 디스크가 면진 디스크가 아니고 정상적인 디스크인 경우, 종 래와 동일하게 내주와 외주의 필터이득값을 동일하게 설정한다.(S7)However, when the loaded disk is not a base disk but a normal disk, the filter gain values of the inner and outer circumferences are set to be the same as in the conventional case (S7).

상기에서 상세히 설명한 바와 같이, 본 발명은 디스크의 내주와 외주를 동일한 포커스 구동 전압으로 포커싱시 출력되는 고주파 신호의 진폭 변화량에 따라 면진 디스크의 여부을 판단하여 면진 디스크이면 내주와 외주의 필터이득값을 서로 다르게 설정하여 면진을 보상함으로써, 노이즈의 발생을 최소화하여 기록 및 재생 특성을 향상시키는 효과가 있다. As described in detail above, in the present invention, the filter gain values of the inner circumference and the outer circumference of the inner circumference and the outer circumference are determined by determining whether the isolating disk is based on the amplitude variation of the high frequency signal outputted when focusing the inner and outer circumferences of the disk with the same focus driving voltage. By setting differently to compensate for isolation, there is an effect of minimizing occurrence of noise to improve recording and reproduction characteristics.

Claims (3)

디스크의 내주에서 포커스 온되는 포커스 구동 전압을 검출한 뒤, 그 전압으로 포커싱시의 고주파 신호를 검출하는 제1 단계와; 상기 제1 단계의 동작이 완료되면, 디스크의 외주로 이동하여 상기 검출된 포커스 구동 전압으로 포커싱하며, 그 때의 고주파 신호를 검출하는 제2 단계와; 상기 제2 단계의 동작이 완료되면, 상기 디스크의 외주와 내주에서 검출된 고주파 신호의 진폭 변화량에 의해 면진 디스크인지의 여부를 판단하는 제3 단계로 이루어진 것을 특징으로 하는 디스크의 면진 판단 방법.Detecting a focus driving voltage focused on the inner circumference of the disk, and detecting a high frequency signal at the time of focusing with the voltage; A second step of moving to the outer periphery of the disk to focus on the detected focus driving voltage when the operation of the first step is completed, and detecting a high frequency signal at that time; And a third step of determining whether or not it is an isolating disk based on the amplitude change amount of the high frequency signal detected at the outer and inner circumferences of the disk when the operation of the second step is completed. 제1항에 있어서, 상기 면진 디스크인지의 여부 판단은 내주의 고주파 신호의 진폭 변화에 비해 외주의 고주파 신호의 진폭 변화가 30%이상인지 판단하는 제1 과정과; 상기 제1 과정의 판단결과 외주의 진폭 변화가 30%이상 이면 면진 디스크로 판단하고, 작으면 정상적인 디스크로 판단하는 제2 과정으로 이루어진 것을 특징으로 하는 디스크의 면진 판단 방법.The method of claim 1, wherein the determination of whether the isolation disk is performed comprises: a first step of determining whether an amplitude change of the high frequency signal of the outer periphery is greater than or equal to 30% compared to a change in the amplitude of the high frequency signal of the inner ring; And a second process of judging that the amplitude of the outer circumference is more than 30% as a result of the judging of the first process, and judging that it is a base disk if the amplitude of the outer periphery is more than 30%. 디스크의 내주에서 포커스 온되는 포커스 구동 전압을 검출한 뒤, 그 전압으로 포커싱시의 고주파 신호를 검출하는 제1 단계와; 상기 제1 단계의 동작이 완료되면, 디스크의 외주로 이동하여 상기 검출된 포커스 구동 전압으로 포커싱하며, 그 때의 고주파 신호를 검출하는 제2 단계와; 상기 제2 단계의 동작이 완료되면, 상기 디스크의 외주와 내주에서 검출된 고주파 신호의 진폭 변화량에 의해 면진 디스크인지의 여부를 판단하는 제3 단계와; 상기 제3 단계의 판단결과 면진 디스크가 아니면 내주와 외주의 필터이득값을 동일하게 설정후 종료하고, 면진 디스크이면 내주의 필터이득값보다 외주의 필터이득값을 높게 설정후 종료하는 제4 단계로 이루어진 것을 특징으로 하는 디스크의 면진 보상 방법.Detecting a focus driving voltage focused on the inner circumference of the disk, and detecting a high frequency signal at the time of focusing with the voltage; A second step of moving to the outer periphery of the disk to focus on the detected focus driving voltage when the operation of the first step is completed, and detecting a high frequency signal at that time; When the operation of the second step is completed, determining whether or not it is an isolating disk based on the amplitude change amount of the high frequency signal detected at the outer and inner circumferences of the disk; As a result of the determination in the third step, if it is not an isolating disk, the filter gain values of the inner and outer lines are set to be the same, and if it is an isolating disk, the filter gain is set higher than the filter gain of the inner line. Isolation of the disk, characterized in that made.
KR1019990060915A 1999-12-23 1999-12-23 Sensing and compensating method for twist of disc KR100595502B1 (en)

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Cited By (1)

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Publication number Priority date Publication date Assignee Title
KR20150137423A (en) 2014-05-29 2015-12-09 한국과학기술원 Modeling method of sequivalent model for isolated structures

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JPS60121555A (en) * 1983-12-02 1985-06-29 Matsushita Electric Ind Co Ltd Shape estimating method of optical information record reproducing carrier
JPH0652565A (en) * 1992-07-31 1994-02-25 Sony Corp Recording and/or reproducing device for disk-shaped recording medium
JPH1083549A (en) * 1996-09-05 1998-03-31 Sanyo Electric Co Ltd Tilt control method for disk player

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60121555A (en) * 1983-12-02 1985-06-29 Matsushita Electric Ind Co Ltd Shape estimating method of optical information record reproducing carrier
JPH0652565A (en) * 1992-07-31 1994-02-25 Sony Corp Recording and/or reproducing device for disk-shaped recording medium
JPH1083549A (en) * 1996-09-05 1998-03-31 Sanyo Electric Co Ltd Tilt control method for disk player

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20150137423A (en) 2014-05-29 2015-12-09 한국과학기술원 Modeling method of sequivalent model for isolated structures

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