公开(公告)号：US4085423A

公开(公告)日：1978-04-18

申请号：US691099

申请日：1976-05-28

申请人： Yoshito Tsunoda ,  Takeshi Maeda ,  Yoshitada Oshida

发明人： Yoshito Tsunoda ,  Takeshi Maeda ,  Yoshitada Oshida

IPC分类号： H04N5/85 ,  G02B27/00 ,  G02B27/09 ,  G11B7/00 ,  G11B7/005 ,  G11B7/09 ,  G11B7/12

CPC分类号： G11B7/0903 ,  G11B7/12

摘要： Information reproducing apparatus for producing information on an optical information recording medium includes a first light source which gives forth a beam of light of a wavelength .lambda..sub.1 and a second light source which gives forth a beam of light of a wavelength .lambda..sub.2 different from the wavelength .lambda..sub.1. An optical element selectively reflects the light of the wavelength .lambda..sub.1 and selectively transmits the light of the wavelength .lambda..sub.2. The first and second light sources, the optical element and the recording medium are positionally arranged so that the light beams from the first and second light sources may be projected on a predetermined position of the recording medium and a substantially identical position to the predetermined position through the optical element, respectively, and the arrangement of these elements is also such that the respective projected light beams may fall on the optical element after being reflected by the recording medium. First and second photodetectors detect light reflected from the optical element and light transmitted light through the same in accordance with the wavelength of the light beams falling on the optical element, respectively, and develop focusing and tracking control signals.

摘要翻译： 用于在光学信息记录介质上产生信息的信息再现装置包括：发出波长为λ1的光束的第一光源和产生波长为λ2的不同波长的光束的第二光源 光学元件选择性地反射波长λ1的光并选择性地透射波长λ2的光。第一和第二光源，光学元件和记录介质被位置地布置成使得来自 第一和第二光源可以分别投影在记录介质的预定位置上，并且通过光学元件分别与预定位置基本相同的位置，并且这些元件的布置也使得各个投影光束可能落在 被记录介质反射后的光学元件。 第一和第二光电检测器分别检测从光学元件反射的光并根据分别落在光学元件上的光束的波长来透过光，并且形成聚焦和跟踪控制信号。

公开(公告)号：US5109374A

公开(公告)日：1992-04-28

申请号：US406519

申请日：1989-09-13

申请人： Yoshito Tsunoda ,  Hiroshi Yasuoka ,  Takeshi Maeda

发明人： Yoshito Tsunoda ,  Hiroshi Yasuoka ,  Takeshi Maeda

IPC分类号： G11B11/10 ,  G11B7/00 ,  G11B7/0025 ,  G11B7/09 ,  G11B7/24 ,  G11B11/105

CPC分类号： G11B11/10584 ,  G11B11/10552 ,  G11B11/10556 ,  G11B11/10576 ,  G11B7/0025 ,  G11B7/24 ,  G11B7/24003

摘要： An optical memory device includes a cylindrically-shaped optical information recording medium and at least one optical head disposed around the information recording medium for irradiating the information recording medium with a light spot for recording or reproduction of information. The optical head has light spot moving means incorporated therein for the irradiation position of the light spot. The recording or reproduction of information is achieved by causing the light spot moving means to perform tracking control so that the light spot follows a desired track in an area within a range of movement of the light spot by the light spot moving means (or an infromation recording zone) in a state in which the relative positional relationship between the optical head and the cylindrically-shaped information recording medium in the direction parallel to the direction of the rotation axis of the information recording medium is fixed, with the optical head being not moved. The device can be constructed so that the position of either the optical head or the cylindrically-shaped information recording medium relative to the other in the direction parallel to the direction of the rotation axis of the information recording medium is mechanically moved, thereby making it possible to cahnge the information recording zone in the range of movement of the light spot by the light spot moving means to another information recording zone.

公开(公告)号：US5084860A

公开(公告)日：1992-01-28

申请号：US551025

申请日：1990-07-11

申请人： Takeshi Maeda ,  Yoshito Tsunoda ,  Kazuo Shigematsu ,  Toshimitsu Kaku

发明人： Takeshi Maeda ,  Yoshito Tsunoda ,  Kazuo Shigematsu ,  Toshimitsu Kaku

IPC分类号： G11B7/007 ,  G11B7/09 ,  G11B7/26 ,  G11B11/105

CPC分类号： G11B7/261 ,  G11B11/10565 ,  G11B11/10578 ,  G11B11/10582 ,  G11B7/0901 ,  G11B7/0938 ,  G11B7/094 ,  G11B7/24082

摘要： A record carrier having a disc-shaped substrate and a recording layer for optically writing information therein is disclosed which includes a guide groove extended in the rotational direction of the record carrier so that a plurality of revolutions of the guide groove are spaced apart from each other in radial directions of the record carrier, and a pit pattern provided between adjacent guide grooves, at positions arranged at intervals in the above rotational direction, for detecting the deviation of a light spot from the center line between adjacent guide grooves. The recording/reproducing operation for this record carrier is performed in such a manner that the first tracking error signal is detected from diffracted light from the guide groove, the second tracking error signal is detected from the pit pattern, and information is recorded in and reproduced from a land formed between adjacent guide grooves in a state that a tracking operation is performed using the first and second tracking error signals. The second tracking error signal detected from the pit pattern is not affected by the tilting of the record carrier and the movement of the light spot. When a tracking signal obtained by adding the first and second tracking error signals to each other, is used in a closed-loop tracking system, a stable tracking operation can be performed. The polarity of the pit pattern is reversed on every track, and hence a polarity pit having a depth of .lambda./4 (where .lambda. indicates the wavelength of a reproducing light beam) is provided in the record carrier, to reverse the polarity of the second tracking signal on every track on the basis of a signal from the polarity pit.

公开(公告)号：US5073880A

公开(公告)日：1991-12-17

申请号：US285584

申请日：1988-12-16

申请人： Takeshi Maeda ,  Yoshito Tsunoda

发明人： Takeshi Maeda ,  Yoshito Tsunoda

IPC分类号： G11B7/09 ,  G11B11/105 ,  G11B21/10

CPC分类号： G11B7/0938 ,  G11B11/10565 ,  G11B11/10578 ,  G11B21/106

摘要： Data recording and/or reproduction on or from a recording medium on which tracking signal detection marks are intermittently provided along each track in a pattern wobbling alternately across the track center line with a very small lateral displacement therefrom, wherein data recording area is defined between the tracking signal detection mark. A servo control system for controlling a write/read light spot so as to follow the track with the aid of a tracking signal obtained by detecting the tracking signal detection marks is provided with a low-pass filter circuit having a cut-off frequency lower than the frequency at which the tracking signal detection marks are detected. A data is recorded or reproduced on or from the recording areas of the recording medium while following the track under the control of the servo system. A blank area where data recording is inhibited is provided between the data recording area and the tracking signal detecting mark (prepit) to suppress interference to the data. A particular access prepit pattern which allows track addresses to be at least approximately detected upon passing of the light spot over the track of the recording medium is previously provided together with synchronizing marks in a synchronizing area.

公开(公告)号：US4855991A

公开(公告)日：1989-08-08

申请号：US10428

申请日：1987-02-03

申请人： Toshimitsu Kaku ,  Yoshito Tsunoda ,  Takeshi Maeda ,  Shigeru Nakamura

发明人： Toshimitsu Kaku ,  Yoshito Tsunoda ,  Takeshi Maeda ,  Shigeru Nakamura

IPC分类号： G11B7/007 ,  G11B7/09 ,  G11B7/095 ,  G11B7/24 ,  G11B27/30

CPC分类号： G11B27/30 ,  G11B20/10203 ,  G11B7/00745 ,  G11B7/09 ,  G11B7/094 ,  G11B7/0956 ,  G11B2220/2537

摘要： An optical disk having a disk-like substrate and a recording layer provided on the substrate. First and second regions are alternately arranged along a rotational direction of the optical disk. The first region includes a pre-formed optically detectable portion having an address area, and the second region has a guide groove serving as an optical guide for a light spot. A track offset detection area is provided for detecting track offset due to inclination of the optical disk and is disposed with respect to the first region and the second region so that the light spot is not affected by the first region and the second region. The track offset detection area is preferably a mirror portion disposed between the first region and the second region.

公开(公告)号：US4293944A

公开(公告)日：1981-10-06

申请号：US810166

申请日：1977-06-27

申请人： Morishi Izumita ,  Takeshi Maeda ,  Yoshito Tsunoda ,  Susumu Sawano

发明人： Morishi Izumita ,  Takeshi Maeda ,  Yoshito Tsunoda ,  Susumu Sawano

IPC分类号： G11B7/0037 ,  G11B7/09 ,  G11B7/095 ,  G11B7/12 ,  G11B17/00

CPC分类号： G11B7/0037 ,  G11B7/0909 ,  G11B7/0953

摘要： Information play-back apparatus comprising a laser source, a recording medium, a photodetector, a first optical system which conducts a laser beam from the laser source to an information track on the recording medium as a read spot, and a second optical system which conducts a reflected laser beam from the information track to the photodetector through an optical element having the unidirectional lens action, said optical element being arranged in a manner to define an angle of about 45 degrees relative to the direction of the information track, and said photodetector having at least four light receiving portions divided symmetrically about two axes such that at least one light receiving portion is in each of the four quadrants formed by two axes, and one of the axes is parallel to the direction of the information track.

摘要翻译： 信息回放装置，包括激光源，记录介质，光电检测器，将来自激光源的激光束传导到作为读取点的记录介质上的信息轨道的第一光学系统，以及第二光学系统， 通过具有单向透镜作用的光学元件从信息轨道到光电检测器的反射激光束，所述光学元件以相对于信息轨道的方向限定约45度的角度的方式布置，并且所述光电检测器具有 至少四个光接收部分围绕两个轴对称地分开，使得至少一个光接收部分在由两个轴形成的四个象限中的每一个中，并且一个轴平行于信息轨道的方向。

公开(公告)号：US4835756A

公开(公告)日：1989-05-30

申请号：US32506

申请日：1987-03-31

申请人： Toshimitsu Kaku ,  Takeshi Maeda ,  Shigeru Nakamura ,  Masaru Ito ,  Kazuo Shigematsu ,  Yoshito Tsunoda

发明人： Toshimitsu Kaku ,  Takeshi Maeda ,  Shigeru Nakamura ,  Masaru Ito ,  Kazuo Shigematsu ,  Yoshito Tsunoda

IPC分类号： G11B7/00 ,  G11B7/005 ,  G11B7/007 ,  G11B7/085 ,  G11B7/09 ,  G11B7/24

CPC分类号： G11B7/0938 ,  G11B7/08505 ,  G11B7/24079 ,  G11B7/24076

摘要： An optical memory apparatus employs an optical disc having a plurality of guide-grooves in spiral and concentrical form and a plurality of flat tracks each arranged between adjacent two of the guide-grooves for recording information thereon, and the depth of the guide-grooves is suitably selected to increase the degree of modulation of a track cross signal, thereby performing a stable cross track counting by the use of the track cross signal and a tracking signal. One feature of the invention relies in that the modulation degree of the track cross signal is in the range between 30 and 60%. A second feature of the invention is that the guide-grooves are formed into a V shape and have an optical depth of .lambda./6 to .lambda./5 (.lambda. is the wavelength of the light used). In accordance with the invention, not ony a stable cross track counting is realized, but also the tracking signal is not practically varied with variations in the depth of the guide-grooves, thereby ensuring a highly accurate and stable tracking control.

摘要翻译： 一种光存储装置采用具有多个螺旋形和同心形状的导向槽的光盘，以及多个平行轨道，每个平行轨迹布置在相邻的两个导槽之间，用于在其上记录信息，并且导向槽的深度为 适当地选择以增加轨道交叉信号的调制度，从而通过使用轨道交叉信号和跟踪信号执行稳定的交叉轨道计数。 本发明的一个特征在于，轨道交叉信号的调制度在30％与60％之间。 本发明的第二个特征是导槽形成为V形，并且具有λ/ 6至λ/ 5的光学深度（λ是所用光的波长）。 根据本发明，不能实现稳定的交叉轨道计数，而且跟踪信号实际上不随着导槽深度的变化而变化，从而确保高精度和稳定的跟踪控制。

公开(公告)号：US4725721A

公开(公告)日：1988-02-16

申请号：US766271

申请日：1985-08-16

申请人： Shigeru Nakamura ,  Yoshito Tsunoda ,  Takeshi Maeda

发明人： Shigeru Nakamura ,  Yoshito Tsunoda ,  Takeshi Maeda

IPC分类号： G02B7/28 ,  G11B7/085 ,  G11B7/09 ,  G11B7/135 ,  G11B7/1374 ,  G11B7/1381

CPC分类号： G11B7/1381 ,  G11B7/08547 ,  G11B7/0908 ,  G11B7/0916 ,  G11B7/1374

摘要： An autofocusing control system makes a position of focusing spot follow for itself a displacement of an information medium. In the autofocusing control system, a single mode semiconductor laser is excited in a multi oscillation mode by returning part of a reflected light beam from the information medium, and a focusing lens having chromatic aberration is used which focuses a laser beam from the semiconductor laser onto a different position along the optical axis of the lens in association with a different laser wavelength.

摘要翻译： 自动对焦控制系统使得聚焦点的位置本身跟随信息介质的位移。 在自动对焦控制系统中，通过使来自信息介质的一部分反射光束返回到多重振荡模式中，单模半导体激光器被激发，并且使用具有色差的聚焦透镜，其将来自半导体激光器的激光束聚焦到 与不同激光波长相关联的沿着透镜的光轴的不同位置。

公开(公告)号：US4949331A

公开(公告)日：1990-08-14

申请号：US875442

申请日：1986-06-17

申请人： Takeshi Maeda ,  Yoshito Tsunoda ,  Kazuo Shigematsu ,  Toshimitsu Kaku

发明人： Takeshi Maeda ,  Yoshito Tsunoda ,  Kazuo Shigematsu ,  Toshimitsu Kaku

IPC分类号： G11B7/007 ,  G11B7/09 ,  G11B7/26 ,  G11B11/105

CPC分类号： G11B7/261 ,  G11B11/10565 ,  G11B11/10578 ,  G11B11/10582 ,  G11B7/0901 ,  G11B7/0938 ,  G11B7/094 ,  G11B7/24082

摘要： A record carrier having a disc-shaped substrate and a recording layer for optically writing information therein is disclosed which includes a guide groove extended in the rotational direction of the record carrier so that a plurality of revolutions of the guide groove are spaced apart from each other in radial directions of the record carrier, and a pit pattern provided between adjacent guide grooves, at positions arranged at intervals in the above rotational direction, for detecting the deviation of a light spot from the center line between adjacent guide grooves. The recording/reproducing operation for this record carrier is performed in such a manner that the first tracking error signal is detected from diffracted light from the guide groove, the second tracking error signal is detected from the pit pattern, and information is recorded in and reproduced from a land formed between adjacent guide grooves in a state that a tracking operation is performed using the first and second tracking error signals. The second tracking error signal detected from the pit pattern is not affected by the tilting of the record carrier and the movement of the light spot. When a tracking signal obtained by adding the first and second tracking error signals to each other, is used in a closed-loop tracking system, a stable tracking operation can be performed. The polarity of the pit pattern is reversed on every track, and hence a polarity pit having a depth of .lambda./4 (where .lambda. indicates the wavelength of a reproducing light beam) is provided in the record carrier, to reverse the polarity of the second tracking signal on every track on the basis of a signal from the polarity pit.

摘要翻译： 公开了一种具有盘形基板和用于在其中光学地写入信息的记录层的记录载体，其包括沿着记录载体的旋转方向延伸的引导槽，使得引导槽的多个转动彼此间隔开 在记录载体的径向方向上设置的凹坑图案，以及设置在相邻引导槽之间的位置，在沿上述旋转方向间隔设置的位置处，用于检测光点与相邻引导槽之间的中心线的偏离。 该记录载体的记录/再现操作以从导槽的衍射光检测第一跟踪误差信号，从凹坑图案检测第二跟踪误差信号并将信息记录并再现 在使用第一和第二跟踪误差信号执行跟踪操作的状态下从形成在相邻引导槽之间的区域。 从凹坑图案检测到的第二跟踪误差信号不受记录载体的倾斜和光点的移动的影响。 当在闭环跟踪系统中使用通过将第一和第二跟踪误差信号彼此相加而获得的跟踪信号时，可以执行稳定的跟踪操作。 凹坑图案的极性在每个轨道上反转，因此在记录载体中提供具有λ/ 4深度（其中λ表示再现光束的波长）的极性凹坑，以反转第二 基于来自极性凹坑的信号在每个轨道上跟踪信号。

公开(公告)号：US4802153A

公开(公告)日：1989-01-31

申请号：US842200

申请日：1986-03-21

申请人： Keiji Kataoka ,  Takeshi Maeda ,  Yoshito Tsunoda

发明人： Keiji Kataoka ,  Takeshi Maeda ,  Yoshito Tsunoda

IPC分类号： G11B7/085 ,  G11B7/09 ,  G11B7/12

CPC分类号： G11B7/08558 ,  G11B7/08511 ,  G11B7/08552 ,  G11B7/1245

摘要： Accessing method and an apparatus therefor in an optical disc apparatus having an acousto-optic light deflector for deflecting a light spot to a different address or different track on an optical disc are disclosed. An auto-focus signal is held at a constant level for a predetermined period when the acousto-optic light deflector deflects the light spot. Thus, an affect caused by coexistence of a plurality of acoustic frequencies in the acoustic-optic device is eliminated and fast light accessing is attained.

摘要翻译： 公开了具有用于将光点偏转到光盘上的不同地址或不同轨道的声光偏转器的光盘装置中的访问方法及其装置。 当声光偏转器偏转光斑时，自动对焦信号被保持在一定的时间段上。 因此，消除了在声光装置中多个声频共存引起的影响，并且实现了快速的光访问。