专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

71. 发明专利

JPH08249748A METHOD AND DEVICE FOR RECORDING/REPRODUCING MAGNETO-OPTICAL INFORMATION 失效
公开(公告)号：JPH08249748A
公开(公告)日：1996-09-27
申请号：JP5594095
申请日：1995-03-15
申请人： HITACHI LTD
发明人： TANAKA YASUTO , KUREBAYASHI MASAAKI , SASAKI TORU , SUZUKI YORIMI , ONISHI KUNIKAZU
IPC分类号： G11B11/10 , G11B11/105
摘要： PURPOSE: To reduce the cross talk and to realize a high density recording by setting the transmission axis of an analyzer so that a difference with two kinds of Kerr rotation angles by signals recorded on adjacent tracks becomes equal. CONSTITUTION: Reflected light 106 from a magneto-optical disk 7 goes to a reflection surface of a second beam splitter 20 through an objective lens 17, a reflection mirror 16, and transmission light 107 and the reflected light 108 are made incident on the analyzers 21 and 22 respectively. Then, they are divided into two luminous flux whose polarization are intersected orthogonally respectively, and the sizes of the Kerr rotation angles are converted into intensity, and a magneto-optical signal recorded on a magneto-optical disk 7 is reproduced by a detection method taking a difference between the signals detected by photodetectors 23, 24, that is, a differential detection method.

72. 发明专利

JPH07261054A OPTICAL TRANSMISSION MODULE AND OPTICAL TRANSMISSION EQUIPMENT USING THE SAME 失效
公开(公告)号：JPH07261054A
公开(公告)日：1995-10-13
申请号：JP4671294
申请日：1994-03-17
申请人： HITACHI LTD
发明人： ONISHI KUNIKAZU , INOUE MASAYUKI
IPC分类号： G02B6/34 , G02B6/293 , G02B6/42 , H01L27/15
摘要： PURPOSE:To provide an optical means for obtaining a practical light utilization efficiency and an optical means for reducing the crosstalk due to stay light as to an optical transmission module which uses a diffraction grating. CONSTITUTION:To obtain a practical light utilization efficiency, the diffraction grating 6 whose diffraction efficiency a diffracted light beam as a received light beam is higher that that to a diffracted light beam as a transmitted light beam and at least >=40% is used. As one means, the diffraction grating 6 which has grating grove 20 formed into a saw-tooth shape so that their groove depth (d) satisfies at least d>=0.3lambda(n0-n1) is used. Here, lambda is the wavelength of the diffracted light beam n0 is the refractive index of the base plate member constituting the diffraction grating 6, and n1 is the refractive index of a peripheral medium brought into contact with the diffraction grating 6.

73. 发明专利

JPH07104154A OPTICAL TRANSMISSION MODULE AND OPTICAL TRANSMITTING DEVICE 失效
公开(公告)号：JPH07104154A
公开(公告)日：1995-04-21
申请号：JP25170093
申请日：1993-10-07
申请人： HITACHI LTD
发明人： ONISHI KUNIKAZU , INOUE MASAYUKI , SUZUKI YOSHIO , FUKUI YUKIO
IPC分类号： G02B6/26 , G02B6/42
摘要： PURPOSE:To provide a two-way optical transmission module which is effective in miniaturizing the device and also reducing the cost by a simple constitution and an optical transmitting device using the module. CONSTITUTION:A light emitting element 1 and a light receiving element 2 are stored in the same package 12, a holographic diffraction grating 6 is installed on the upper, or lower surface of a cover glass 2 arranged on a package opening part. At the time of transmitting, light beams 100 emitted from the light emitting element 1 are transmitted through the diffraction grating 6 and condensed on the end face 5 of an optical fiber 4 by a lens 3. Meanwhile, at the time of receiving, receiving light beams 105 emitted from the end face 5 of the optical fiber 4 reach the diffraction grating 6 through the lens 3, and the beams 105 are diffracted by the diffraction grating 6, and + 1st order diffracted light beams 108 are condensed on the photodetecting surface of the light receiving element 7. Thus, a transmission signal is received from signal light transmitted through the optical fiber 4.

74. 发明专利

JPH06231504A OPTICAL DISK AND OPTICAL DISK DEVICE USING THE SAME, AND DATA DEVICE USING THE OPTICAL DISK DEVICE 失效
公开(公告)号：JPH06231504A
公开(公告)日：1994-08-19
申请号：JP13216893
申请日：1993-06-02
申请人： HITACHI LTD
发明人： NAKAJIMA JUNJI , SASAKI TORU , ONISHI KUNIKAZU , SUZUKI YOSHIO , KUREBAYASHI MASAAKI , MIYAMOTO MAKOTO
IPC分类号： G11B7/00 , G11B7/0045 , G11B7/005 , G11B7/135 , G11B7/24 , G11B11/10 , G11B11/105 , G11B13/00
摘要： PURPOSE:To obtain an optical disk which can make a light spot serving for reproduction of signals smaller than the actual light spot, and eventually improve the resolution when the signals are reproduced and has a light controlling layer with reversibly stable and good repeatability. CONSTITUTION:Phase pits 134 corresponding to data signals are formed on a transparent substrate 101. A light controlling layer 102 having magnetic films 102a, 102b changing the reflectivity or polarizing characteristic reversibly in accordance with the temperature or intensity of the magnetic field is provided over the pits 13. The optical disk is thus constituted. When data is to be reproduced, a laser light 2 is cast from the side of the transparent substrate 101 and moreover an initial magnetic field Hint is impressed at a position prior to the casting position.

75. 发明专利

JPH06162527A OPTICAL HEAD AND OPTICAL INFORMATION DEVICE USING IT 失效
公开(公告)号：JPH06162527A
公开(公告)日：1994-06-10
申请号：JP31460092
申请日：1992-11-25
申请人： HITACHI LTD
发明人： SASAKI TORU , INOUE MASAYUKI , SHIMANO TAKESHI , KITADA YASUO , ONISHI KUNIKAZU
IPC分类号： G11B7/09 , G11B7/135
摘要： PURPOSE:To obtain an optical head by which a focus error signal on an astigma tism method and a tracking error signal on a push/pull method are detected in one lot by means of one optical system without deteriorating magneto-optical signals, also by which the adjustment of the tracking error signal is made in dependently from the focus error signal, and further by which the mixing of a track crossing signal into the focus error signal is reduced. CONSTITUTION:The device is provided with, between a beam splitter 4 by which a servo signal is separated from a magneto-optical signal and a photodetector 30 for servo signal, a belt-like area without grating, a diffraction grating 27 which is provided with two grating areas having mutually different grating lines across the belt-like area, a detecting lens 29 and a cylinder lens 40. Also, the diffracted rays of the diffraction grating including 0th-order diffracted light (direct transmitted light) are guided to the photodetector 30, the focus error signal by the astigmatism method is detected by means of the 0th-order diffracted light, and the tracking error signal is detected by means of a + or -1st- order diffracted light.

76. 发明专利

JPH06139622A OPTICAL INFORMATION CARRIER AND REPRODUCING METHOD FOR OPTICAL SIGNAL 失效
公开(公告)号：JPH06139622A
公开(公告)日：1994-05-20
申请号：JP28770292
申请日：1992-10-26
申请人： HITACHI LTD
发明人： NAKAJIMA JUNJI , SASAKI TORU , ONISHI KUNIKAZU , SUZUKI YOSHIO , KUREBAYASHI MASAAKI , MIYAMOTO MAKOTO
IPC分类号： G11B7/00 , G11B7/005 , G11B7/24
摘要： PURPOSE:To obtain an optical information carrier recording phase pits beyond the conventional reproducing solution and an optical signal reproducing method for the same. CONSTITUTION:As an optical information carrier, a first phase pit row with a depth d1 and a second phase pit row with a depth d2 are provided. By irradiating the optical information carrier with a light spot of a first wavelength lambda1 and a light spot of a second wavelength lambda2, d1 is set to an odd number multiple of lambda1/4 and a natural number multiple of lambda2/2 and d2 is set to a natural number multiple of lambda1/2 and an odd number multiple of lambda2/4. Since only the first phase pit is detected in the first spot and only the second phase pit is detected in the second spot, the row interval of the pit row is made an half of the spot diameter.

77. 发明专利

JPH06131698A OPTICAL DISK AND OPTICAL SIGNAL RECORDING AND REPRODUCING DEVICE USING THE SAME 失效
公开(公告)号：JPH06131698A
公开(公告)日：1994-05-13
申请号：JP27967392
申请日：1992-10-19
申请人： HITACHI LTD
发明人： ONISHI KUNIKAZU , NAKAJIMA JUNJI , SASAKI TORU , MIYAMOTO MAKOTO , KUREBAYASHI MASAAKI , SUZUKI YOSHIO
IPC分类号： G11B7/00 , G11B7/004 , G11B7/24
摘要： PURPOSE:To detect the focusing and tracking control signals of a light spot for reproduction use and simultaneously to improve optical resolution substantially in an optical disk device. CONSTITUTION:A high temperature or high light intensity area 101a to decrease reflectivity is formed in the light spot 101 by providing a light control layer on the phase pit 50 of an optical disk, and resolution can be improved by decreasing the light spot substantially. Since the light spot 101 goes to an area with high reflectivity uniformly by defocusing, the focusing and tracking control signals of the light spot for reproduction can be detected.

78. 发明专利

JPH05135399A OPTICAL HEAD 失效
公开(公告)号：JPH05135399A
公开(公告)日：1993-06-01
申请号：JP29547291
申请日：1991-11-12
申请人： HITACHI LTD
发明人： SASAKI TORU , ONISHI KUNIKAZU , INOUE MASAYUKI , SAITO AKIRA , KITADA YASUO
IPC分类号： G02B7/18 , G02B7/182 , G11B7/135
摘要： PURPOSE:To miniaturize the constitution and to make the cost low by constituting a beam shaping prism with a reflection type and a transmission type beam shaping prisms having the same incident planes and the same light-emitting surfaces, making an angle between an incident optical axis and a light-emitting optical axis a right angle and selecting an optical constant so as to cancel and correct a color aberration each other. CONSTITUTION:A luminous flux 2 outgoing from a semiconductor laser element 1 is made a parallel luminous flux 4 by a collimate lens 3 and incident on the incident plane 13a of the first reflection type beam shaping prism 13. The luminous flux 15 refracted on the surface 13a is reflected from the reflection surface 13b and becomes the luminous fluxes 16, 17 and refracted on the incident plane 14a of a second transmission type beam shaping prism 14 and becomes the luminous fluxes 18, 19 and is emitted from the light-emitting surface 14b. The angle between the optical axis 4a of the luminous flux 4 and the optical axis 19a of the luminous flux 19 is made 90 degree and the optical constant is set so as to cancel the color aberration by the fluctuation of the wavelength of the prisms 13, 14 and to correct it. Thus, the luminous flux is deflected 90 degree without using a reflection mirror, etc., and an optical head is miniaturized and made a low cost.

79. 发明专利

JPH0581696A MULTIBEAM SEPARATION LIGHT HEAD DEVICE 失效
公开(公告)号：JPH0581696A
公开(公告)日：1993-04-02
申请号：JP24107491
申请日：1991-09-20
申请人： HITACHI LTD
发明人： INOUE MASAYUKI , SASAKI TORU , ONISHI KUNIKAZU
IPC分类号： G11B7/135
摘要： PURPOSE:To simply control incident light quantity fluctuation on an objective lens by configuring plural luminous fluxes from a fixed optical system to cross on the objective lens respectively while a moving optical system is located within a required region. CONSTITUTION:Optical axes of two or plural number of laser parallel luminous fluxes from semiconductor laser 1 and 5 of a fixed optical system 30 are tilted for a minute angle with respect to each other in an opposite direction so that these parallel luminous fluxes are crossed each other on a lens 13 so long as a moving optical system 20, which has a mirror 12 and the objective lens 13, is located between the inner and outer peripherals of an optical disk 14. And the portion, in which two or plural number of parallel luminous fluxes are overlapped, is fully made larger than the effective diameter of the lens 13 so that the motion of the lens 13 does not practically fluctuate the light quantity incident on the lens 13. As a result, a multibeam separation light head device, which simply controls incident light quantity fluctuation on an objective lens, is provided.

80. 发明专利

JPH04289530A OPTICAL DEVICE 失效
公开(公告)号：JPH04289530A
公开(公告)日：1992-10-14
申请号：JP5430691
申请日：1991-03-19
申请人： HITACHI LTD
发明人： ONISHI KUNIKAZU , IMADA RITSUO , SASAKI TORU , INOUE MASAYUKI
IPC分类号： G02B7/28 , G11B7/135
摘要： PURPOSE:To allow positions in the optical-axis direction of respective condensed light spots to coincide with each other by using a normal lens including the chromatic aberration to correct the relative positional deviation in the opticalaxis direction of condensed light spots due to the chromatic aberration at the time of condensing plural laser light different in wavelength by one objective lens. CONSTITUTION:The laser luminous flux from a semiconductor laser element 1a is converted to a luminous flux of parallel rays by a collimator lens 2a and is made incident on a converging lens 50 through a beam shaping prism 3 and a beam splitter 4a and is converted to a convergent luminous flux 101a which has the condensed light spot in a prescribed position on the optical axis. The laser luminous flux from a laser element 1b is made incident on a diverging lens 51 and is converted to a divergent luminous flux having a virtual light emission point in a prescribed position on the optical axis. The convergent luminous flux 101a and the divergent luminous flux 101b are allowed to pass the same optical path through a wavelength selecting prism 5 and are reflected by a turning-up mirror 6 and are condensed on the recording face of an optical disk 8 by an objective lens 7, and condensed light spots 102a and 102b coincide with each other.

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式