公开(公告)号：EP0618569A1

公开(公告)日：1994-10-05

申请号：EP94105187.2

申请日：1994-03-31

Applicant: SONY CORPORATION

Inventor： Miyazono, Shunichi, Sony Corporation

IPC: G11B7/00 ,  G11B7/09

CPC classification number: G11B11/10576 ,  G11B7/005 ,  G11B7/08511 ,  G11B7/0908

Abstract: A focusing servo system comprises a signal generating unit (7), a focusing servo unit (9), a zero crossing detecting unit, a search signal generating unit and a system controller (11). The signal generating unit (7) generates a focus error signal on the basis of the position of an objective lens (3a), through which a light beam is projected on an optical recording medium (1), with respect to a direction perpendicular to the recording surface of the optical recording medium (1) by using the reflected light beam from the recording surface of the optical recording medium (1), a read signal representing information read from the optical recording medium (1) on the basis of the reflected light beam and a focus acquisition enable range signal representing a focus acquisition enable range on the basis of the read signal. The focusing servo unit (9) receives the focus error signal from the signal generating unit (7) and executes a focusing servo control operation for focusing the objective lens (3a) on the basis of the focus error signal. The zero crossing detecting unit receives the focus error signal from the signal generating unit and detects a zero crossing point in the focus error signal. The search signal generating unit generates a down-search signal and an up-search signal respectively for driving the objective lens (3a) for movement toward and away from the recording surface of the optical recording medium (1). The system controller receives the focus acquisition enable range signal from the signal generating unit and a zero crossing detection signal from the zero crossing detecting unit, selectively supplies the search signals generated by the search signal generating means and the focus error signal generated by the signal generating unit (7) to the focusing servo unit, and executes a control operation on the basis of the focus acquisition enable range signal received from the signal generating means (7) and the zero crossing detection signal received from the zero crossing detecting unit to supply the focus error signal provided by the signal generating means instead of the search signal provided by the search signal generating unit in a predetermined time after the start of the movement of the objective lens (3a) away from the recording surface of the optical recording medium (1) during the movement of the objective lens (3a) from its initial position away from the recording surface of the optical recording medium (1).

Abstract translation: 聚焦伺服系统包括：信号生成单元（7），一个聚焦伺服单元（9），一个过零点检测单元，搜索信号发生单元和系统控制器（11）。 所述信号产生单元的物镜（3a）中，通过其的光束被相对于投射到光学记录介质（1）的方向垂直于所述的位置的基础上，（7）基因率的聚焦误差信号 通过使用反射光束从光学记录介质的记录表面的光学记录介质（1）的记录面（1），表示信息的读取信号从光学记录介质读取（1）的反射光的基础上 光束和焦点获取启动表示焦点获取读出信号的基础上使能范围范围信号。 聚焦伺服单元（9）接收来自信号发生单元的聚焦误差信号（7），执行用于聚焦物镜（3a）的聚焦误差信号的基础上，一个聚焦伺服控制操作。 零交叉点检测单元接收来自信号发生单元的聚焦误差信号并检测聚焦误差信号的零交叉点。 搜索信号发生单元基因率下行搜索信号和分别到上行搜索信号，用于从光学记录介质的记录表面驱动物镜（3A），用于运动朝向和离开（1）。 该系统控制器接收到焦点获取启动从信号产生单元，并从零交叉点检测单元的零交叉检测信号范围的信号，选择性地供给由所述搜索信号产生装置，并通过信号产生所产生的聚焦误差信号生成的搜索信号 单元（7）到聚焦伺服单元，并且执行焦点获取的基础上操作的控制使能范围内的信号接收的信号产生装置（7）和从过零接收检测单元，以供给所述零交叉检测信号 由信号产生的提供聚焦误差信号的装置，而不是由搜索信号生成部的物镜（3A）的移动的开始之后的预定时间提供的搜索信号从光学记录介质的记录表面相距（1 ）所述的物镜（3a）中的从其初始位置从理论值的所述记录面的运动期间离开 È光学记录介质（1）。

公开(公告)号：EP0304932B1

公开(公告)日：1994-02-16

申请号：EP88113952.1

申请日：1988-08-26

Applicant: FUJITSU LIMITED

Inventor： Yanagi, Shigenori FUJITSU LIMITED ,  Sasaki, Masateru FUJITSU LIMITED ,  Minami, Akira FUJITSU LIMITED ,  Iwamoto, Toshitaka FUJITSU LIMITED ,  Tanaka, Shigeyoshi FUJITSU LIMITED

IPC: G11B7/09 ,  G11B7/085

CPC classification number: G11B7/0945 ,  G11B7/08511 ,  G11B7/0908 ,  G11B7/094

公开(公告)号：EP0284377B1

公开(公告)日：1993-10-27

申请号：EP88302578.5

申请日：1988-03-24

Applicant: SONY CORPORATION

Inventor： Wachi, Shigeaki c/o Sony Corporation ,  Kumagai, Eiji c/o Sony Corporation

IPC: G11B7/09 ,  G11B7/08

CPC classification number: G11B7/08511

公开(公告)号：EP0539019A1

公开(公告)日：1993-04-28

申请号：EP92308504.7

申请日：1992-09-17

Applicant: SONY CORPORATION

Inventor： Wachi, Shigeaki

IPC: G11B7/09

CPC classification number: G11B7/08511 ,  G11B7/0909

Abstract: A focus servo device for use in an optical disk apparatus. The device comprises a reproducer for irradiating a light beam emitted from a light source to an optical disk through an objective lens, and detecting an RF signal from a focus error signal on the basis of the return light beam reflected from the optical disk; a maximum-minimum detector for detecting the maximum and the minimum of the RF signal obtained from the reproducer; and a control signal generator for generating a focus servo signal obtained from the reproducer and also with the maximum and the minimum of the RF signal detected by the maximum-minimum detector. Since the focus servo lock-in control is performed in conformity with the detected maximum and minimum values of the reproduced RF signal, the apparatus is capable of recording information on and/or reproducing the same from any optical disk regardless of the kind thereof.

Abstract translation: 一种用于光盘装置的聚焦伺服装置。 该装置包括：再现器，用于通过物镜将从光源发射的光束照射到光盘，并且基于从光盘反射的返回光束从聚焦误差信号中检测RF信号; 最大值 - 最小值检测器，用于检测从再现器获得的RF信号的最大值和最小值; 以及控制信号发生器，用于产生从再现器获得的聚焦伺服信号，并且还产生由最大值 - 最小值检测器检测到的RF信号的最大值和最小值。 由于聚焦伺服锁定控制是根据检测到的再现RF信号的最大值和最小值执行的，所以该设备能够在任何光盘上记录和/或再现信息，而不管其类型如何。

公开(公告)号：EP0520559A3

公开(公告)日：1993-04-28

申请号：EP92201794.2

申请日：1992-06-19

Applicant: Philips Electronics N.V.

Inventor： Leenknegt, George Alois Leonie

IPC: G11B7/09

CPC classification number: G11B7/08511 ,  G11B7/0916

Abstract: A radiation source (1) in an optical detection arrangement generates a beam (2). The beam (2) is focused on a plane (5) of a medium (6) by means of an optical system (3,4). With the aid of a focus actuator (8) a focal point (9) of the beam (2) may be moved relative to the plane (5). A focus detection unit (7) derives a focus error signal (FE) which, within a predetermined focus range (B), is indicative of the distance (dl) between the focal point (9) and the plane (5). Furthermore, the focus detection unit (7) generates a focus condition signal (CA) denoting that the focal point (9) is positioned outside said focus range (B). A control circuit (33) derives a control signal (FA) for the actuator (8) from the focus error signal (FE) so as to keep the focal point (9) substantially in the plane (5). The detection arrangement further includes a signal generator (44,41,50,51) responsive to the focus position signal (CA), for generating a substitute control signal (FA) varying with time for the focus actuator (8) so as to bring the focal point (9) back to the focus range (B) if the focus position signal (CA) denotes that the focal point (9) has transgressed the focus range (B). Generating the substitute control signal (FA) is commenced in a direction depending on the sign of the focus error (FE) at the instant the focal point (9) departs from the focus range. When a control circuit is used comprising an integrator (41) for generating a control signal (FA) in response to the integrated value of the focus error signal (FE), the integrated value at the output of the integrator (41) is pre-eminently suitable for use as an initial value of the substitute signal (FA).

公开(公告)号：EP0532246A3

公开(公告)日：1993-04-21

申请号：EP92308084.0

申请日：1992-09-07

Applicant: International Business Machines Corporation

Inventor： Dente, James John ,  Fennema, Alan August

IPC: G11B7/09 ,  G02B7/04

CPC classification number: G11B7/08511 ,  G11B7/0908

Abstract: In a focus acquire system on an optical disk recorder, a focus error signal FES 33 has a peak amplitude of 34 at the start of a linear region 38 within which occurs a desired focus position 99. The FES 33 is modified to produce a modified FES 105 which has a peak amplitude 106 occurring closer to the desired focus position 99 than the occurrence of peak amplitude 34 of the FES. The FES 33 is differentiated to produce a differentiated FES 100. The differentiated FES 100 is then subtracted from FES 33 to produce the modified FES 105. The modified FES 105 is compared with a threshold 109 and a near-focus position is detected upon agreement at point 110. This narrows the area 107 within which in-focus position is to be found.

公开(公告)号：EP0520559A2

公开(公告)日：1992-12-30

申请号：EP92201794.2

申请日：1992-06-19

Applicant: Philips Electronics N.V.

Inventor： Leenknegt, George Alois Leonie

IPC: G11B7/09

CPC classification number: G11B7/08511 ,  G11B7/0916

Abstract: A radiation source (1) in an optical detection arrangement generates a beam (2). The beam (2) is focused on a plane (5) of a medium (6) by means of an optical system (3,4). With the aid of a focus actuator (8) a focal point (9) of the beam (2) may be moved relative to the plane (5). A focus detection unit (7) derives a focus error signal (FE) which, within a predetermined focus range (B), is indicative of the distance (dl) between the focal point (9) and the plane (5). Furthermore, the focus detection unit (7) generates a focus condition signal (CA) denoting that the focal point (9) is positioned outside said focus range (B). A control circuit (33) derives a control signal (FA) for the actuator (8) from the focus error signal (FE) so as to keep the focal point (9) substantially in the plane (5). The detection arrangement further includes a signal generator (44,41,50,51) responsive to the focus position signal (CA), for generating a substitute control signal (FA) varying with time for the focus actuator (8) so as to bring the focal point (9) back to the focus range (B) if the focus position signal (CA) denotes that the focal point (9) has transgressed the focus range (B). Generating the substitute control signal (FA) is commenced in a direction depending on the sign of the focus error (FE) at the instant the focal point (9) departs from the focus range. When a control circuit is used comprising an integrator (41) for generating a control signal (FA) in response to the integrated value of the focus error signal (FE), the integrated value at the output of the integrator (41) is pre-eminently suitable for use as an initial value of the substitute signal (FA).

Abstract translation: 光学检测装置中的辐射源（1）产生光束（2）。 光束（2）通过光学系统（3,4）聚焦在介质（6）的平面（5）上。 借助聚焦致动器（8），光束（2）的焦点（9）可以相对于平面（5）移动。 焦点检测单元（7）导出在预定焦点范围（B）内指示焦点（9）和平面（5）之间的距离（d1）的焦点误差信号（FE）。 此外，焦点检测单元（7）产生表示焦点（9）位于所述焦点范围（B）之外的焦点条件信号（CA）。 控制电路（33）从聚焦误差信号（FE）导出用于致动器（8）的控制信号（FA），从而将焦点（9）基本保持在平面（5）中。 该检测装置进一步包括响应聚焦位置信号（CA）的信号发生器（44,41,50,51），用于产生随聚焦致动器（8）随时间变化的替代控制信号（FA），以便使聚焦致动器 如果焦点位置信号（CA）表示焦点（9）超过聚焦范围（B），则焦点（9）返回焦点范围（B）。 生成替代控制信号（FA）的方向取决于焦点（9）离开聚焦范围时刻的聚焦误差（FE）的符号。 当使用包括用于响应聚焦误差信号（FE）的积分值产生控制信号（FA）的积分器（41）的控制电路时，积分器（41）输出端的积分值被预先存储， 非常适合用作替代信号（FA）的初始值。

公开(公告)号：EP0432658A2

公开(公告)日：1991-06-19

申请号：EP90123530.9

申请日：1986-02-21

Applicant: Deutsche Thomson-Brandt GmbH

Inventor： Baas, Dieter ,  Kurz, Arthur ,  Füldner, Friedrich

IPC: G11B7/09 ,  G11B7/085

CPC classification number: G11B7/0945 ,  G11B7/08511 ,  G11B7/0909 ,  G11B7/094

Abstract: Bei einem Verfahren zum Fokussieren eines Lichtstrahls wird der Lichtstrahl mittels eines optischen Systems auf einen optischen Aufzeichnungsträger fokussiert. Das optische System besteht aus einer Lichtquelle und einem mittels eines Stellgliedes SG beweg­baren Objektivs 20. Der Aufzeichnungsträger reflektiert den Lichtstrahl auf eine Anzahl von Photoelementen A, B, C und D. Aus deren Ausgangsspannungen wird durch Subtraktion und Additi­on ein erstes Steuersignal gewonnen, das über einen Regelver­stärker RV dem Stellglied SG zugeführt wird, so daß ein Regel­kreis gebildet wird. Bei wechselspannungsmäßig offenem, gleich­spannungsmäßig jedoch geschlossenem Regelkreis wird dem Stell­glied SG eine zweite Steuerspannung U s zugeführt und verändert. Wenn der Lichtstrahl auf den Aufzeichnungsträger fokussiert ist, wird der Regelkreis wieder vollständig geschlossen. Der zu diesem Zeitpunkt angenommene Wert der zweiten Steuerspannung U s wird beibehalten und liegt als Vorspannung am Stellglied SG an.

Abstract translation: 在聚焦点到达之后，调节电路闭合，并且在焦点处检测到的脉冲调制值被存储。 由脉冲调制电压产生的控制电压（Us）用作致动器（4）的偏移电压。 控制电压（Us）由交流分量叠加。

公开(公告)号：EP0404449A2

公开(公告)日：1990-12-27

申请号：EP90306531.6

申请日：1990-06-15

Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.

Inventor： Yamada, Shinichi ,  Moriya, Mitsuro ,  Yamaguchi, Hiroyuki

IPC: G11B7/085 ,  G11B7/09

CPC classification number: G11B7/08529 ,  G11B7/08511

Abstract: A data-track search apparatus is provided with a tracking error detection unit for detecting a positioning error between a light beam on a record carrier and a track, a moving unit for moving the light beam on the record carrier in a direction traversing the tracks on the record carrier, a focusing control failure detection unit for detecting a focusing control failure, and a control unit for controlling the moving unit in response to an output signal from the tracking error detection unit during the search for an aimed track. The control unit regulates the moving unit so as not to accelerate but to decelerate the latter in the event of the focusing control failure.

Abstract translation: 数据轨道搜索装置设有跟踪误差检测单元，用于检测记录载体上的光束与轨道之间的定位误差;移动单元，用于沿着穿过轨道的方向在记录载体上移动光束; 记录载体，用于检测聚焦控制故障的聚焦控制故障检测单元，以及用于在搜索目标轨迹期间响应于来自跟踪误差检测单元的输出信号来控制移动单元的控制单元。 控制单元调节移动单元，以便在聚焦控制失败的情况下不加速而减速。

公开(公告)号：EP0004476B1

公开(公告)日：1985-10-30

申请号：EP79300489.6

申请日：1979-03-27

Applicant: DISCOVISION ASSOCIATES

Inventor： Ceshkovsky, Ludwig ,  Dakin, Wayne Ray

IPC: G11B7/08 ,  H04N5/76

CPC classification number: G11B7/12 ,  G11B7/005 ,  G11B7/08 ,  G11B7/08511 ,  G11B7/09 ,  G11B7/0908 ,  G11B7/0941 ,  G11B19/28 ,  G11B21/10