Optical head with built-in semiconductor laser, objective lens and 1/4
wavelength plate
    3.
    发明授权
    Optical head with built-in semiconductor laser, objective lens and 1/4 wavelength plate 失效
    光头采用内置半导体激光器,物镜和+ E,fra 1/4 + EE波长板

    公开(公告)号:US5555232A

    公开(公告)日:1996-09-10

    申请号:US336782

    申请日:1994-11-09

    摘要: An optical head has a semiconductor laser for emitting light, a collimator lens for converting the light from the laser into a parallel light beam, a semiconductor substrate for reflecting the light beam, and an objective lens for focussing the light beam reflected from the substrate on the optical disk. A 1/4 wavelength plate is situated between the substrate and the objective lens. A beam splitter which transmits the light from the laser and reflects the light returning from the disk is provided between the collimator lens and the substrate. Following the beam splitter, a collective lens, a cylindrical lens and an optical detector are arranged in this order on an optical path for the returning light. A light receiving element for outputting a signal corresponding to the intensity of the light received is formed on the semiconductor substrate, and a polarizing film is formed on the surface thereof.

    摘要翻译: 光头具有用于发射光的半导体激光器,用于将来自激光的光转换为平行光束的准直透镜,用于反射光束的半导体基板和用于将从基板反射的光束聚焦的物镜 光盘。 A + E,fra 1/4 + EE波片位于基片和物镜之间。 在准直透镜和基板之间设置有从激光器透射光并反射从光盘返回的光的分束器。 在分束器之后,在用于返回光的光路上依次布置集体透镜,柱面透镜和光学检测器。 在半导体衬底上形成用于输出与所接收的光的强度相对应的信号的光接收元件,并且在其表面上形成偏振膜。

    Apparatus for detecting unused sector on record medium
    4.
    发明授权
    Apparatus for detecting unused sector on record medium 失效
    用于检测记录介质上未使用扇区的装置

    公开(公告)号:US5202877A

    公开(公告)日:1993-04-13

    申请号:US619918

    申请日:1990-11-30

    申请人: Tsuneo Yanagida

    发明人: Tsuneo Yanagida

    摘要: An apparatus for detecting unused sectors in an optical disk or opto-magnetic disk including an envelope detection circuit for detecting an envelope of a read signal to derive an envelope detection signal when data is recorded in a data area of sector. Sector mark and address marks recorded in an identification area are detected to derive sector mark detection signal is generated and address mark detection signals, and an interpolated mark signal corresponding to a synchronizing signal recorded in the data area in accordance with the sector mark detection signal and address mark detection signals. When the envelope detection signal is not produced, the generation of the interpolated mark signal is inhibited. Thus when the synchronizing signal is not detected in the data area and the generation of the interpolated signal is inhibited, the relevant sector is detected as the unused sector.

    摘要翻译: 一种用于检测光盘或光磁盘中的未使用扇区的装置,包括用于在数据被记录在扇区的数据区域中时检测读信号的包络以导出包络检测信号的包络检测电路。 检测记录在识别区域中的扇区标记和地址标记,以产生扇区标记检测信号和地址标记检测信号,以及与根据扇区标记检测信号记录在数据区域中的同步信号相对应的内插标记信号,以及 地址标记检测信号。 当不产生包络检测信号时,内插标记信号的产生被禁止。 因此,当在数据区域中未检测到同步信号并且内插信号的产生被禁止时,相关扇区被检测为未使用的扇区。

    Bias-Magnetic field generating system of photo-magnetic recording device
    6.
    发明授权
    Bias-Magnetic field generating system of photo-magnetic recording device 失效
    光磁记录装置的偏磁场产生系统

    公开(公告)号:US5159584A

    公开(公告)日:1992-10-27

    申请号:US762788

    申请日:1991-09-19

    IPC分类号: G11B11/105

    摘要: A photo-magnetic (magneto-optic) recording device having recording medium in the form of a rotating magnetic disc having magnetic characteristics in a direction perpendicular to its surface has a pickup head (7) disposed on one side of the disc and movable radially of the disc to scan selected areas of the disc. On the side of the disc opposite to that on which the pickup head is located, there are provided a plurality of coils (8) generating a bias-magnetic field applied to the disc. The coils are disposed in overlapping arrangement with their centers disposed on a line extending radially of the disc. The coils are energized by electric circuitry which comprises means for sensing the position of the pickup head and energizing a respective coil located in position to apply a bias-magnetic to the area of the disc scanned by the pickup head.

    摘要翻译: 具有在与其表面垂直的方向上具有磁特性的旋转磁盘形式的记录介质的光磁(磁光)记录装置具有设置在盘的一侧上的拾取头, 光盘扫描光盘的选定区域。 在盘的与拾取头所在位置相反的一侧,设置有产生施加到盘的偏磁场的多个线圈(8)。 线圈以重叠的布置布置,其中心设置在盘的径向延伸的线上。 线圈由电路供电,该电路包括用于感测拾取头的位置并激励位于适当位置的相应线圈的装置,以将偏磁施加到由拾取头扫描的盘的区域。

    Sector mark detecting apparatus in optical disc apparatus
    7.
    发明授权
    Sector mark detecting apparatus in optical disc apparatus 失效
    光盘装置中的扇区标记检测装置

    公开(公告)号:US5083303A

    公开(公告)日:1992-01-21

    申请号:US343654

    申请日:1989-04-27

    IPC分类号: G11B7/085 G11B20/12 G11B27/30

    摘要: Based on an output signal of a sector mark reading circuit reading a sector mark signal representing a sector mark area, the interval in which the next sector mark signal is to be detected is anticipated, and a quasi-sector mark is generated at a time when the next sector mark is to be detected in each sector. Even if the sector mark reading fails, the sector mark will be able to be output at an accurate timing. Also, if the read sector mark signal, which is mis-detected or not, is determined, a highly reliable sector mark signal may be produced.

    摘要翻译: 基于读取表示扇区标记区域的扇区标记信号的扇区标记读取电路的输出信号,预期下一个扇区标记信号将被检测的间隔,并且产生准扇区标记, 将在每个扇区中检测下一扇区标记。 即使扇区标记读取失败,扇区标记将能够以准确的时序输出。 此外,如果确定了未被检测到的读扇区标记信号,则可以产生高度可靠的扇区标记信号。

    Method and apparatus for detecting track crossings on an optical disc
    8.
    发明授权
    Method and apparatus for detecting track crossings on an optical disc 失效
    用于检测光盘上的轨道交叉的方法和装置

    公开(公告)号:US4757487A

    公开(公告)日:1988-07-12

    申请号:US734774

    申请日:1985-05-16

    摘要: In a method of detecting track crossings on an optical disc, a light source irradiates a light beam onto an optical disc having guide tracks in the form of a recess and the light beam is reflected and diffracted into a zero order light beam and positive and negative primary light beams. The light beams are defocused so as to produce interference patterns between the zero light beam and the positive and negative primary light beams. The interference patterns are detected by a four split light detector disposed between two parts of a two split detector. The outputs of the detectors are fed to an adder and to a subtractor for producing a sum signal and a difference signal respectively. The sum signal and difference signal are fed to a phase detector. Defocusing of the light beams is effected by a focusing coil to which is fed the amplified output of an adder of a reference signal controlled by a control circuit.

    摘要翻译: 在一种检测光盘上的轨道交叉的方法中,光源将光束照射到具有凹陷形式的导轨的光盘上,并且光束被反射并衍射成零级光束,并且正和负 主光束。 光束散焦,从而产生零光束与正,负主光束之间的干涉图案。 干涉图案由设置在两个分离检测器的两个部分之间的四个分开的光检测器检测。 检测器的输出被馈送到加法器和减法器,用于分别产生和信号和差分信号。 和信号和差分信号被馈送到相位检测器。 光束的散焦通过聚焦线圈实现,聚焦线圈馈送由控制电路控制的参考信号的加法器的放大输出。

    Method of processing information signal with respect to opto-magnetic
record medium
    9.
    发明授权
    Method of processing information signal with respect to opto-magnetic record medium 失效
    相对于光磁记录介质处理信息信号的方法

    公开(公告)号:US4472748A

    公开(公告)日:1984-09-18

    申请号:US336319

    申请日:1981-12-31

    IPC分类号: G11B5/02 G11B11/10 G11B11/105

    CPC分类号: G11B11/10517 G11B11/10536

    摘要: In a method of recording an information signal in an opto-magnetic record disc which has an easily magnetizable axis perpendicular to its surface, a constant erasing light beam and a modulated recording light beam are focussed by a single objective lens on adjacent tracks and an external magnetic field is applied to the record medium. The erasing and recording operations can be carried out at the same time by inverting the polarity of the external magnetic field track by track.

    摘要翻译: 在将信息信号记录在具有与其表面垂直的易磁化轴的光磁记录盘中的方法中,恒定的擦除光束和调制的记录光束被相邻轨道上的单个物镜聚焦,外部 磁场被施加到记录介质上。 擦除和记录操作可以通过使轨道上的外部磁场轨迹的极性反转来同时进行。