Using Plural Polarized Or Polarizing Optical Elements Patents (Class 369/110.04)
  • Patent number: 11163753
    Abstract: Novel tools and techniques are provided for implementing data storage and/or retrieval, and, more particularly, for implementing data associations. In various embodiments, an associations rules engine might query data aggregation data services to determine whether a first data object (which along with a first relationship rule that indicates a one-to-one relationship between the first data object and a corresponding second data object) is associated with one or more third data objects; might abstract the first data object, the first relationship rule, and the one or more third data objects; might update, in a metadata catalog, a catalog entry corresponding to the first data object with one or more associations among various data objects; and might provide a requesting computing system with access to the catalog entry corresponding to the first data object, the computing system performing one or more computational tasks using the associations stored in the catalog entry.
    Type: Grant
    Filed: November 8, 2018
    Date of Patent: November 2, 2021
    Assignee: CenturyLink Intellectual Property LLC
    Inventor: Ronald A. Lewis
  • Patent number: 11115643
    Abstract: A method for adjusting an optical system, and to an adjustment system for use in an optical system where the adjustment system comprises a predetermined reference object having known visible reference object features, a sensor system, a data evaluation module and an image processor. The data evaluation module receives captured image data and determines at least two visible reference object features of the predetermined reference object arranged in a field of view, and determines position data containing a position deviation of an image of the object to be examined or, in the case of a stereoscopic optical system, of a first and second half-image of the object to be examined. The image processor ascertains an optical distortion of the visible reference object features and sets a corresponding geometric rectification of received image data.
    Type: Grant
    Filed: September 11, 2017
    Date of Patent: September 7, 2021
    Inventor: Holger Muller
  • Patent number: 10942135
    Abstract: A dark field inspection system may include an illumination source to generate an illumination beam, one or more illumination optics to direct the illumination beam to a sample at an off-axis angle along an illumination direction, a detector, one or more collection optics to generate a dark-field image of the sample on the detector based on light collected from the sample in response to the illumination beam, and a radial polarizer located at a pupil plane of the one or more collection optics, where the radial polarizer rejects light with radial polarization with respect to an apex point in the pupil plane corresponding to specular reflection of the illumination beam from the sample.
    Type: Grant
    Filed: September 20, 2019
    Date of Patent: March 9, 2021
    Assignee: KLA Corporation
    Inventors: Jenn-Kuen Leong, Daniel Kavaldjiev, Guoheng Zhao
  • Patent number: 10821892
    Abstract: A notification device for a mobile unit according to an embodiment includes, for example: a storage unit that stores therein first sound data; a sound output control unit that outputs a notification sound based on the first sound data, from a sound output unit provided on the mobile unit; a generation unit that generates second sound data by performing predetermined processing on a location of sound falling, while causing the first sound data to follow a cycle of the notification sound, the predetermined processing being different from processing on a location of sound rising; and a light source drive control unit that causes a light source unit provided on the mobile unit to emit light in accordance with the intensity of a sound expressed by the second sound data.
    Type: Grant
    Filed: September 7, 2017
    Date of Patent: November 3, 2020
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventor: Noboru Nagamine
  • Patent number: 10809193
    Abstract: An inspection apparatus or lithographic apparatus includes an optical system and a detector. The optical system includes a non-linear prismatic optic. The optical system is configured to receive zeroth and first diffraction order beams reflected from a diffraction target and separate first and second polarizations of each diffraction order beam. The detector is configured to simultaneously detect first and second polarizations of each of the zeroth and first diffraction order beams. Based on the detected first and second polarizations of one or more diffraction orders, an operational parameter of a lithographic apparatus can be adjusted to improve accuracy or precision in the lithographic apparatus. The optical system can include a plurality of non-linear prismatic optics. For example, the optical system can include a plurality of Wollaston prisms.
    Type: Grant
    Filed: March 25, 2019
    Date of Patent: October 20, 2020
    Assignees: ASML Netherlands B.V., ASML Holding N.V.
    Inventors: Marinus Johannes Maria Van Dam, Richard Carl Zimmerman
  • Patent number: 9887585
    Abstract: Disclosed are various embodiments of a guided surface waveguide transmit system. One embodiment of the guided surface waveguide transmit system includes a guided surface waveguide probe configured to transmit a guided surface wave along a lossy conducting medium. The system further includes a controller device configured to receive load status data and signal for the guided surface waveguide probe to adjust transmission of the guided surface wave based at least in part on the load status data.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: February 6, 2018
    Assignee: CPG TECHNOLOGIES, LLC
    Inventors: James F. Corum, Kenneth L. Corum, Joseph F. Pinzone
  • Patent number: 9013965
    Abstract: Provided are an optical pickup device and an optical disk drive including the same. The optical pickup device includes a quarter-wave plate (QWP) that is disposed parallel to an objective lens and a reflection mirror that reflects a beam back onto the QWP after the beam passed through the QWP. The optical pickup device also includes a polarization mirror that is disposed between the objective lens and the QWP, and which reflects the beam which is generated from a light source onto the QWP, and allows the beam reflected by the reflection mirror to pass through to the objective lens.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: April 21, 2015
    Assignee: Toshiba Samsung Storage Technology Korea Corporation
    Inventors: Ji-sun Ahn, Ui-yol Kim
  • Patent number: 8730775
    Abstract: Multi-level recording is quite effective for attaining a larger capacity and a higher transfer rate in the case of an optical disk; however, with conventional technologies, a SIGNAL-TO-NOISE RATIO of a signal deteriorates along with an increase in a multi-level degree, creating a factor for limitations to the multi-level degree. In order to solve problems, when optical information is recorded by use of a standing wave occurring due to interference between two light beams, at least one of the two light beams is modulated in multi-stages. Further, at the time of regeneration, a regeneration reference beam is caused to interfere with respective polarization components of a regeneration beam, the polarization components being orthogonal to each other, thereby concurrently generating not less than three interference beams differing in interference phase from each other before being detected.
    Type: Grant
    Filed: January 6, 2011
    Date of Patent: May 20, 2014
    Assignee: Hitachi Consumer Electronics Co., Ltd.
    Inventor: Hideharu Mikami
  • Patent number: 8509040
    Abstract: An optical pickup device includes a polarization diffraction grating to diverge an optical beam reflected from an optical disc and an optical detector to receive the optical beam diverged by the polarization diffraction grating, a polarization of 0 order diffracted light diffracted through the polarization diffraction grating is substantially perpendicular to that of a +1 order diffracted light diffracted therethrough, and a polarization filter having a plurality of domains is mounted between the polarization diffraction grating and the optical detector.
    Type: Grant
    Filed: April 15, 2010
    Date of Patent: August 13, 2013
    Assignee: Hitachi Media Electronics Co., Ltd.
    Inventor: Kazuyoshi Yamazaki
  • Patent number: 8427921
    Abstract: In the present invention, to improve CD read/write characteristics having poor image height characteristics, a third light emitting source emitting a third laser beam for CD is disposed on an optical axis of an objective lens. Thereby, the third laser beam emitted from the third light emitting source travels along the optical axis of the objective lens, thus generating no coma aberration in the third laser beam. Furthermore, in the present invention, a second light emitting source emitting a second laser beam for DVD and a first light emitting source emitting a first laser beam for BD are disposed across the third light emitting source. Thereby the phase propagation directions of coma aberrations in the first and second laser beams coincide with each other. Adjustment of the coma aberration in one of the laser beams enables the coma aberration in the other laser beam to be adjusted.
    Type: Grant
    Filed: July 10, 2012
    Date of Patent: April 23, 2013
    Assignees: SANYO Electric Co., Ltd., SANYO Optec Design Co., Ltd.
    Inventors: Ryoichi Kawasaki, Tohru Hotta
  • Patent number: 8289819
    Abstract: An information reproducing apparatus has a medium with a linear tracking mark extending in a scanning direction and a linear data mark extending in a direction orthogonal to the scanning direction. A light control unit irradiates the data mark with a first near-field light polarized in the scanning direction and irradiates the tracking mark with a second near-field light polarized in the direction orthogonal to the scanning direction. A detector detects light scattered by the data mark and the tracking mark irradiated with the first near-field light and the second near-field light, respectively. A signal processing unit processes a first output signal from the detector corresponding to the detected light scattered by the data mark and processes a second output signal from the detector corresponding to the detected light scattered by the tracking mark.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: October 16, 2012
    Assignee: Seiko Instruments Inc.
    Inventors: Manabu Oumi, Yasuyuki Mitsuoka, Norio Chiba, Nobuyuki Kasama, Kenji Kato, Takashi Niwa
  • Patent number: 8147069
    Abstract: A lighting device, including a first light source emitting light of a first wavelength; a second light source close to the first source, emitting light of a second wavelength in almost a same direction as that of the first source; a third light source located emitting light of a third wavelength in a direction different from that of the first and second sources; a coupling optical system coupling light from the first and second sources; another coupling optical system coupling light from the third source; and a light path synthesizer synthesizing a light path of light from the first, second and third sources, wherein the light path synthesizer includes a first surface reflecting light from the first source and transmitting light from the second and third sources and a second surface unparallel with the first surface, reflecting light from the second source and transmitting light from the third source.
    Type: Grant
    Filed: July 27, 2009
    Date of Patent: April 3, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Manabu Seo, Hiroshi Akiyama, Shigeru Oouchida, Yukiko Hamano, Goichi Akanuma
  • Patent number: 8130622
    Abstract: An optical pickup apparatus includes a light generating unit to generate a light to record or reproduce information, an objective lens to focus the light generated from the light generating unit onto a disk, and a multi-sectional polarizer disposed on a light path between the light generating unit and the objective lens and divided into a plurality of sectors having their individual optical axes.
    Type: Grant
    Filed: April 16, 2010
    Date of Patent: March 6, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Seong-su Park, Soo-han Park, Bong-gi Kim, Ichiro Morishita, Myoung-seok Kim, Jung-woo Hong
  • Patent number: 8023369
    Abstract: Disclosed herein are aspects of optical tape technology, tape manufacturing, and tape usage. Methods and systems of tape technology disclose optical tape media including: configurations, formulations, markings, and structure; optical tape manufacturing methods, systems, and apparatus methods and systems including: curing processes, coating methods, embossing, drums, testing, tracking alignment stamper strip; optical tape methods and systems including: pick up head adapted for the disclosed optical tape; and optical tape uses including optical storage media devices for multimedia applications.
    Type: Grant
    Filed: November 30, 2009
    Date of Patent: September 20, 2011
    Assignee: Oracle America, Inc.
    Inventor: Tzuo-Chang Lee
  • Publication number: 20110170396
    Abstract: In the present invention, to improve CD read/write characteristics having poor image height characteristics, a third light emitting source emitting a third laser beam for CD is disposed on an optical axis of an objective lens. Thereby, the third laser beam emitted from the third light emitting source travels along the optical axis of the objective lens, thus generating no coma aberration in the third laser beam. Furthermore, in the present invention, a second light emitting source emitting a second laser beam for DVD and a first light emitting source emitting a first laser beam for BD are disposed across the third light emitting source. Thereby the phase propagation directions of coma aberrations in the first and second laser beams coincide with each other. Adjustment of the coma aberration in one of the laser beams enables the coma aberration in the other laser beam to be adjusted.
    Type: Application
    Filed: January 7, 2011
    Publication date: July 14, 2011
    Applicants: SANYO Electric Co., Ltd.
    Inventors: Ryoichi KAWASAKI, Tohru Hotta
  • Patent number: 7859977
    Abstract: An optical pick-up including a fold mirror having an achromatic quarter-wave plate coating is provided. To allow the thin film coating to efficiently provide the quarter-wave retardation, the optical pick-up is configured such that the polarization of light incident on the fold mirror is at a predetermined angle. According to one embodiment, the predetermined angle is provided by rotating the light sources. According to another embodiment, the predetermined angle is provided by rotating a plane containing the light sources and the beam combiners. In each embodiment, the beam combiners and the fold mirror are arranged along the same axis to further improve efficiency.
    Type: Grant
    Filed: August 22, 2007
    Date of Patent: December 28, 2010
    Assignee: JDS Uniphase Corporation
    Inventors: Kim Leong Tan, Karen Denise Hendrix
  • Publication number: 20100097901
    Abstract: In a particular embodiment, an optical transducer includes at least three optically conductive blades arranged symmetrically about a center gap. The optical transducer is adapted to receive polarized light from a light source and to focus the polarized light onto a recording medium while conserving polarization of the polarized light.
    Type: Application
    Filed: October 16, 2008
    Publication date: April 22, 2010
    Applicant: Seagate Technology LLC
    Inventors: William Albert Challener, Julius Kurt Hohlfeld, Adnan Rebei
  • Patent number: 7639588
    Abstract: The amount of reflected light from an adjacent layer in a multilayer optical disc is reduced by means of a combination of half-wave plates having different optical axes and a flat mirror. The polarization direction of the reflected light from a target layer is changed without changing the polarization direction of reflected light from the adjacent layer so as to detect a signal from the target layer alone. Because no stray light is introduced into the tracking error signal or focus signal, the laser light irradiated position can be controlled with high accuracy. This makes it possible to accurately determine the laser irradiated position during reading and writing, thereby enhancing signal quality. Because no reflected light from the adjacent layer is introduced into the data signal, a data signal with reduced error can be obtained.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: December 29, 2009
    Assignee: Hitachi Media Electronics Co., Ltd.
    Inventors: Shigeharu Kimura, Takeshi Shimano
  • Patent number: 7525880
    Abstract: An information reproducing apparatus has a light source for generating linearly polarized light, a medium having linear marks disposed in overlapping relation to one another, and an optical head disposed between the light source and the medium and having a fine aperture. A polarized light control portion in the light source controls the linearly polarized light to pass through the fine aperture of the optical head to generate near-field light having a preselected polarization direction and to irradiate the linear marks of the medium with the near-field light so that the preselected polarization direction of the near-field light is orthogonal to a longitudinal axis of each of the linear marks. A detector detects light scattered by the linear mark irradiated with the near-field light.
    Type: Grant
    Filed: October 15, 1999
    Date of Patent: April 28, 2009
    Assignee: Seiko Instruments Inc.
    Inventors: Manabu Oumi, Yasuyuki Mitsuoka, Norio Chiba, Nobuyuki Kasama, Kenji Kato, Takashi Niwa
  • Publication number: 20090016192
    Abstract: The invention provides reference patterns marked on a non-data side of an optical disc. When the optical disc, according to the invention, is installed within an optical information recording apparatus, the reference patterns enable an optical pick-up unit of the optical information recording apparatus to register at at least one reference radial position on the no-data side of the optical disc. The at least one reference radial position is for assisting the optical pick-up unit to record a label on the non-data side of the optical disc.
    Type: Application
    Filed: July 10, 2007
    Publication date: January 15, 2009
    Inventors: William Wang, Jerome Wu, Hank Yang, Lester Chen, Tzu-Pang Chiang, Ta-Yuan Lee
  • Patent number: 7417936
    Abstract: An optical pickup includes a laser light source, an objective lens which focuses light emitted from the laser light source on an optical information storing medium, an optical path changer which changes a proceeding path of the light emitted from the laser light source, a polarization changer which changes the polarization of an incident light to make the polarization of light reflected by the optical information storing medium and reentering the laser light source different from that of the light emitted from the laser light source, so that noise generated due to interference by the light reflected by the optical information storing medium and reentering the laser light source is reduced, and a photodetector which receives incident light reflected by the optical information storing medium and sequentially passing through the objective lens and the optical path changer and detects an information signal and/or an error signal.
    Type: Grant
    Filed: November 12, 2003
    Date of Patent: August 26, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ki-bok Kim, No-jun Kwak, Jong-ryull Kim
  • Patent number: 7224661
    Abstract: As a ½ wave plate constituted by laminating two wave plates, a wave plate where temperature dependence of a phase difference is reduced is provided. In a wave plate constituted by laminating a first wave plate having a phase difference ?1 (deg.) and an optical axis azimuth ?1 (deg.), and a second wave plate having a phase difference ?2 (deg.) and an optical axis azimuth ?2 (deg.), the phase difference ?1 (deg.) of the first wave plate and the phase difference ?2 (deg.) of the second wave plate are set to 360n+180 (n=0, 1, 2 . . . ), and an angle formed by polarization planes of incident light and emitted light is ? (deg.). In this case, the first wave plate and the second wave plate are laminated so as to satisfy ?1=(90+?/2)/2 and ?2=?1+90+?/2.
    Type: Grant
    Filed: April 20, 2004
    Date of Patent: May 29, 2007
    Assignee: Toyo Communication Equipment Co., Ltd.
    Inventor: Masayuki Ooto
  • Patent number: 7016290
    Abstract: In an optical information medium comprising an information recording layer having a mark train of marks and spaces, the mark train is read out by scanning it with a laser beam and detecting a light intensity change pattern of reflected laser beam. Provided that the reflected laser beam includes polarized light components which define an angle ? with the mark train, a polarized light component giving ?=0 is x0 component, and a polarized light component giving ?=90° is y0 component, the mark train is read out utilizing at least a light intensity change of x0 component. When pits or recorded marks having a size approximate to or below the resolution limit are read out, the present invention allows high read outputs to be obtained and prevents omission of readout signals.
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: March 21, 2006
    Assignees: TDK Corporation, National Institute of Advanced Industrial Science and Technology
    Inventors: Takashi Nakano, Hisako Fukuda, Junji Tominaga, Nobufumi Atoda, Takashi Kikukawa
  • Patent number: 6940801
    Abstract: An optical recording medium, an optical recording and reproducing method, and an apparatus that can record and reproduce multilevel information at a high density and with a high S/N ratio. Recording light emitted from a light source is collimated by a collimation lens and introduced into a polarization rotary device. Recording light transmitted by the polarization rotary device is focused by an objective lens onto an optical recording medium. In response, a photo-induced birefringence is recorded on the optical recording medium. Multilevel recording is performed by controlling a voltage applied to the polarization rotary device to change a polarization angle ? of recording light. Reproduction is performed by detecting light reflected from the optical recording medium with an analyzer and a detector.
    Type: Grant
    Filed: October 29, 1998
    Date of Patent: September 6, 2005
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Tsutomu Ishii, Katsunori Kawano, Kazuo Baba, Kiichi Ueyanagi
  • Patent number: 6920101
    Abstract: An optical disk device has an aperture of an objective lens in an incoming path of a beam from a semiconductor laser to an optical disk formed larger than an aperture in a return path from the optical disk or an aperture is varied in recording and in reproduction. This configuration improves recording/reproducing ability since light is focused on an optical disk with high numerical aperture. In addition, since reflected light from the optical disk is detected with low numerical aperture, margins for tilt and defocus are not reduced. Furthermore, since unnecessary signal components contained in the reflected light can be eliminated, a S/N (signal-to-noise ratio) of an information signal also increases. Thus, a high-performance optical disk device can be obtained. Alternatively, by varying the aperture of an objective lens in recording and in reproduction, an optical disk device in which recording density and recording quality are increased without deteriorating reproduction quality can be obtained.
    Type: Grant
    Filed: July 10, 2003
    Date of Patent: July 19, 2005
    Assignee: Matsushita Electric Industrial, Co., Ltd.
    Inventors: Youichi Saitoh, Junichi Asada, Yuichi Takahashi, Seiji Nishiwaki, Kenji Nagashima, Kazuo Momoo, Junji Nagaoka
  • Publication number: 20040228256
    Abstract: A pickup for a magneto-optical recording medium is provided, which improves quality of reproduced signals by eliminating a phase difference between the polarizations and is capable of coping with magneto-optical recording media of different recording/reproducing systems. A return light beam of light reflected by a magneto-optical recording medium is polarized and separated into ± first-order diffracted lights through a light-branching diffraction element provided between a light source and an objective lens. The ± first-order diffracted lights are compensated for their phases through first and second phase compensation elements so that there is no phase difference between the polarizations, and are, further, polarized and separated through the first and second polarization/separation elements, and are received by first and second light detectors.
    Type: Application
    Filed: May 14, 2004
    Publication date: November 18, 2004
    Inventors: Tetsuo Ueyama, Kohji Minami, Tomoyuki Miyake, Yasuo Nakata
  • Publication number: 20040202089
    Abstract: An optical pick-up device includes a light source (2), a polarized light beam converter (4), a splitter (6), a collimating lens (7), and a photo-detector (9). A linear polarized light beam with a first type of polarized component and a second type of polarized component is emitted from the light source, and passes through the polarized light beam converter. The first type of polarized component is converted into the second type of polarized component by the polarized light beam converter. Then part of the light beam with the second type of polarized component passes through the splitter and is focused onto an optical disc (8) by the collimating lens. The optical disc reflects the light beam that contains recorded information read from the optical disc. The reflected light beam passes back through the collimating lens, is reflected by the splitter, and is received by the photo-detector.
    Type: Application
    Filed: April 9, 2004
    Publication date: October 14, 2004
    Inventor: Jyh-Chain Lin
  • Patent number: 6804185
    Abstract: A variable optical unit is provided with at least two phase-shift regions for providing light with phase differences. Phase-shift amount of the phase-shift region is adjusted by the applied voltage in accordance with birefringence of an information medium. A light beam emitted from a light source is incident on the variable optical unit through a collimator lens and a beam splitter. The light beam is polarized in accordance with the aforementioned phase-shift amount of the variable optical unit and converged by an objective lens to radiate the information medium. The reflected light polarized due to the effect of the birefringence of the information medium is polarized again according to the phase-shift amount of the variable optical unit. The reflected light is thereby polarized in the direction in which the beam splitter can reflect the reflected light and then the reflected light reflected by the beam splitter is detected by the condenser lens and an optical detector.
    Type: Grant
    Filed: December 18, 2000
    Date of Patent: October 12, 2004
    Assignee: Pioneer Corporation
    Inventors: Ikuya Kikuchi, Takanori Maeda, Mitsuru Sato, Masayuki Iwasaki
  • Patent number: 6801491
    Abstract: A focus error detecting apparatus and a focus error detecting method of an optical pickup in which the system is not easily influenced by track transversal noises and an optical disc thickness error and which can be used together with a 3-beam system or a DPD system. The return light from an optical disc is divided to a first optical path and a second optical path by a hologram device, a predetermined astigmatism is applied to the light on each divided optical path, the light is received and detected by a first detector and a second detector, and a focusing error signal is obtained by predetermined arithmetic operations.
    Type: Grant
    Filed: February 23, 2000
    Date of Patent: October 5, 2004
    Assignee: Pioneer Corporation
    Inventors: Masakazu Ogasawara, Takuma Yanagisawa, Sakashi Ohtaki
  • Publication number: 20030223345
    Abstract: An optical disk apparatus includes a light source for emitting light in a prescribed wavelength range, an objective lens system for causing the light emitted from the light source to be focused onto a storage disk, and a reproduction signal system for causing return light from the storage disk to be conduced to a detector. The light emitted from the light source has a direction of polarization parallel to a recoding track of the storage disk. The objective lens system has transmission factors for s-polarized light and p-polarized light that are defined relative to the objective lens system. The transmission factor for s-polarized light is greater than the transmission factor for p-polarized light.
    Type: Application
    Filed: November 13, 2002
    Publication date: December 4, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Kazushi Uno, Koichi Tezuka
  • Publication number: 20030156525
    Abstract: The above-discussed and other problems and deficiencies of the prior art are overcome or alleviated by the several methods and apparatus of the present invention for a block-by-block data retrieval method and system, wherein the data is stored in a multiple layer polarization selective, wavelength selective, or a combination of polarization selective and wavelength selective films.
    Type: Application
    Filed: November 15, 2002
    Publication date: August 21, 2003
    Inventors: Bunsen Fan, Sadeg M. Faris
  • Patent number: 6594042
    Abstract: An optical element that receives a first incident light and a second incident light through a main surface and allowing the first and second incident lights to be transmitted therethrough, the first and second incident lights being linearly polarized lights having substantially orthogonal polarizing directions and having different wavelengths &lgr;1 and &lgr;2 respectively, the optical element receiving a first reflected light and a second reflected light generated when the first and second incident lights are reflected from a reflector through the other face, and allowing the first and second reflected lights to be transmitted therethrough again, the optical element has a polarizing hologram that allows the first incident light, the second incident light, and the second reflected light to be transmitted therethrough upon receiving these lights and that diffracts the first reflected light upon receiving this light; and at least one wavelength plate that varies at least one of polarizing states of all of the f
    Type: Grant
    Filed: December 12, 2001
    Date of Patent: July 15, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Junichi Asada, Seiji Nishiwaki, Youichi Saitoh
  • Publication number: 20030107977
    Abstract: In an optical information medium comprising an information recording layer having a mark train of marks and spaces, the mark train is read out by scanning it with a laser beam and detecting a light intensity change pattern of reflected laser beam. Provided that the reflected laser beam includes polarized light components which define an angle &thgr; with the mark train, a polarized light component giving &thgr;=0 is x0 component, and a polarized light component giving &thgr;=90° is y0 component, the mark train is read out utilizing at least a light intensity change of x0 component. When pits or recorded marks having a size approximate to or below the resolution limit are read out, the present invention allows high read outputs to be obtained and prevents omission of readout signals.
    Type: Application
    Filed: October 15, 2002
    Publication date: June 12, 2003
    Applicants: TDK CORPORATION, National Inst. of Advanced Ind. Science and Tech.
    Inventors: Takashi Nakano, Hisako Fukuda, Junji Tominaga, Nobufumi Atoda, Takashi Kikukawa
  • Patent number: 6512733
    Abstract: The present invention provides an optical recording method, optical recording apparatus, optical reading method, and optical reading apparatus which are capable of high density recording an d high speed recording, and high speed reading. In recording, a recording light comprising a plurality of polarization distributions corresponding to the data information; is generated, and irradiated onto an optical recording medium to thereby record a plurality of polarization distributions of the recording light on the optical recording medium as photo-induced birefringence. In reading, a reading light having a uniform polarization distribution is irradiated onto the recording medium in which the data information has been recorded previously, and the polarization distribution of the transmitted light or reflected light in the optical recording medium is read as the polarization distribution of the reproducing light.
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: January 28, 2003
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Katsunori Kawano, Tsutomu Ishii, Kazuo Baba
  • Patent number: 6504811
    Abstract: An optical information storage unit for reproducing information recorded on lands and grooves of a magneto-optical recording medium by means of a reflected light obtained from a luminous flux which has been emitted from a light source, irradiated onto the recording medium and reflected from the recording medium. The optical information storage unit includes a first wave plate on which the reflected light from the magneto-optical recording medium is incident; a diffraction grating on which the light having been transmitted through the first wave plate is incident; a second wave plate on which the light having been transmitted through the diffraction grating is incident; and a polarization detecting unit on which the light having been transmitted through the second wave plate is incident.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: January 7, 2003
    Assignee: Fujitsu Limited
    Inventor: Yasuaki Morimoto
  • Patent number: 6278681
    Abstract: There is provided an optical head including a laser diode chip, a lens for focusing lights onto an object, an optical separator for separating lights reflected from the object, from an optical axis of a light directing towards the lens from the laser diode chip, and a photodiode chip receiving lights having been separated from the optical axis by the optical separator. The optical separator is defined by first and second sidewalls, and first to fourth outer surfaces, and has first and second inner planes both being inclined relative to the first outer surface. A light enters the first outer surface, passes through the first and second inner planes, leaves the optical separator at the third outer surface, and is focused onto the object by the lens. The light having been reflected by the object enters the third outer surface, and is reflected at the second inner plane by the remaining half.
    Type: Grant
    Filed: March 22, 1999
    Date of Patent: August 21, 2001
    Assignee: NEC Corporation
    Inventor: Tsuyoshi Nagano