公开(公告)号：US5235591A

公开(公告)日：1993-08-10

申请号：US641309

申请日：1991-01-15

申请人： Shigeru Nakamura ,  Eiichi Seya ,  Seiichi Mita ,  Masuo Kasai ,  Masahiro Ojima ,  Hiroshi Yasuoka ,  Motoyasu Terao ,  Yoshinori Miyamura ,  Takeshi Nakao ,  Kiyoshi Matsumoto ,  Yoshihiro Hamakawa

发明人： Shigeru Nakamura ,  Eiichi Seya ,  Seiichi Mita ,  Masuo Kasai ,  Masahiro Ojima ,  Hiroshi Yasuoka ,  Motoyasu Terao ,  Yoshinori Miyamura ,  Takeshi Nakao ,  Kiyoshi Matsumoto ,  Yoshihiro Hamakawa

IPC分类号： G11B7/12 ,  G11B7/14 ,  G11B33/14

CPC分类号： G11B7/14 ,  G11B33/14 ,  G11B7/122

摘要： A separation type optical head according to the present invention includes at least a light source portion for emitting collimated beams, a focusing device (a focusing lens) for focusing the collimated beams onto an information recording surface of an optical disc medium, a focal point control mechanism for the position of the spot on the information recording surface, and a photo-detection portion for receiving beams reflected by the information recording surface. The structure is divided into a fixed portion including the light source portion and the photo-detection portion and a movable portion including the focusing device (focusing lens) and the focal point control mechanism. At least the movable portion of the separation type optical head is movably accommodated n a frame (sealing case) for the optical head so as to prevent irregular vibrations of the movable portion due to high speed air flows or turbulence. Furthermore, a focal point control mechanism of an air float type may be employed in the movable portion of the separation type optical head so as to actively utilize the high speed air flow generated due to the rotation of the disc medium to perform a rough adjustment of the focal point of the focusing device.

摘要翻译： 根据本发明的分离型光学头至少包括用于发射准直光束的光源部分，用于将准直光束聚焦到光盘介质的信息记录表面上的聚焦装置（聚焦透镜），焦点控制 在信息记录表面上的位置的机构，以及用于接收由信息记录表面反射的光束的光检测部分。 该结构被分为包括光源部分和光检测部分的固定部分和包括聚焦装置（聚焦透镜）和焦点控制机构的可动部分。 至少分离型光学头的可移动部分可移动地容纳在用于光学头的框架（密封壳体）中，以防止由于高速空气流动或湍流引起的可移动部分的不规则振动。 此外，可以在分离型光学头的可动部分中采用气浮式的焦点控制机构，以便主动地利用由于盘介质的旋转而产生的高速气流来进行粗略调整 聚焦装置的焦点。

公开(公告)号：US4084181A

公开(公告)日：1978-04-11

申请号：US761120

申请日：1977-01-21

申请人： Seiichi Mita ,  Hiroshi Kuroda ,  Hisashi Nakamura

发明人： Seiichi Mita ,  Hiroshi Kuroda ,  Hisashi Nakamura

IPC分类号： G11B20/02 ,  H04N9/64 ,  H04N9/81 ,  H04N11/10 ,  H04N9/32 ,  H04N7/08

CPC分类号： H04N11/10 ,  H04N9/64 ,  H04N9/81

摘要： A color television signal processing apparatus is provided for reproducing a chrominance signal from a color television signal transmitted or recorded in such a manner that the chrominance signal is compressed in time scale and that the compressed chrominance signal is superposed on the horizontal blanking period signal of the color television signal in a time division manner. This apparatus includes a circuit for generating a clock pulse used for expanding the time scale of the compressed chrominance signal comprising a signal generator driven by a sample pulse derived from a reference signal in a color television signal and producing low and high frequency signals, a reset pulse generating circuit which compares a reference reset pulse derived from the reference signal with a comparison reset pulse generated from selfoscillating circuit, and a clock pulse generator driven by the output signals of the signal generator and the reset pulse generator. In this way, a correct clock pulse which may be used for expanding the compressed chrominance signal is obtained even when the reference signal in the color television signal temporarily disappears.