Patents by Inventor Tatsuhiro Kobayashi

Tatsuhiro Kobayashi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7440370
    Abstract: A method for determining a read power of a laser beam includes a step of setting a power of a laser beam to a recommended recording power Pw? and forming a recording mark train including at least one of a recording mark having a length shorter than a resolution limit and a blank region having a length shorter than the resolution limit in an optical recording disc, thereby recording test data therein. The method also includes a step of setting the power of the laser beam to a recommended read power Pr? and reproducing the test data recorded in the optical recording disc, a step of judging whether or not signal characteristics of a reproduced signal obtained by reproducing the test data satisfies reference conditions, and determining an optimum read power of the laser beam based on the result of the judgment.
    Type: Grant
    Filed: August 30, 2004
    Date of Patent: October 21, 2008
    Assignee: TDK Corporation
    Inventors: Masashi Kuwahara, Takayuki Shima, Junji Tominaga, Takashi Kikukawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi
  • Publication number: 20080158718
    Abstract: A magnetic recording medium enhances the quality of a reproducing signal. The magnetic recording medium has a servo pattern formed in a servo pattern area on at least one surface of a disk-shaped substrate by a concave/convex pattern having convex portions (recording areas) and concave portions (non-recording areas), and a data track pattern formed by the concave/convex pattern in a data recording area on the at least one surface of the disk-shaped substrate. In a state where recording data is not recorded in the data recording area, the convex portions in the servo pattern area are DC-magnetized, and the convex portions in the data recording area are AC-magnetized.
    Type: Application
    Filed: December 27, 2007
    Publication date: July 3, 2008
    Applicant: TDK Corporation
    Inventors: Tatsuhiro KOBAYASHI, Makoto MORIYA
  • Patent number: 7394744
    Abstract: A reproduction apparatus is capable of reproducing information recorded on information recording media including at least a super RENS recording medium. The reproduction apparatus includes: an optical head that receives laser light that has been reflected or transmitted by the information recording medium and photoelectrically converts the laser light to an electric signal; a signal processing circuit that extracts an AC component from the electric signal and attenuates the AC component by a predetermined attenuation; an amplitude controlling circuit that controls an amplitude of an electric signal outputted from the signal processing circuit so as to become a predetermined amplitude; and a reproduction circuit that reproduces information recorded on the medium based on an electric signal outputted from the amplitude controlling circuit. An information recording medium testing apparatus includes the reproduction apparatus and a test information generating circuit that generates test information.
    Type: Grant
    Filed: April 7, 2005
    Date of Patent: July 1, 2008
    Assignee: TDK Corporation
    Inventors: Takashi Kikukawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi
  • Publication number: 20070274185
    Abstract: An optical disc has a data management area in a region on a radially inward side. Management information is recorded in the data management area as recording marks and spaces. The optical disc also has a data recording area on the outside of the data management area. Data to be read is recoded in the data recording area as recording marks and spaces. The information readout density of the data recording area is higher than that of the data management area. The read power of a readout laser beam during readout can be set smaller in the data management area than in the data recording area. In this manner, the read stability is significantly increased without reducing the information readout density.
    Type: Application
    Filed: May 14, 2007
    Publication date: November 29, 2007
    Applicant: TDK CORPORATION
    Inventors: Takashi Kikukawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi, Tsutomu Aoyama
  • Publication number: 20070247990
    Abstract: A method for determining recording laser power on a super-resolution optical recording medium, on which information is recorded on a super-resolution optical recording medium by irradiating a laser beam modulated into a recording pulse train according to recording data to thereby form a recording mark train including recording marks and spaces smaller than the resolution limit of a reproduction optical system and recording marks and spaces equal to or larger than the resolution limit, is provided. At the time of recording, the method determines a minimum value and a maximum value of recordable laser powers determined by test-writing before recording, and determines a maximum value of a recordable range of laser power by adding to the minimum value one-third of a difference between the maximum value of the recordable laser powers and the minimum value. The method determines an optimal range of recording laser power from the minimum value of recordable laser powers to the maximum value of the recordable range.
    Type: Application
    Filed: April 6, 2007
    Publication date: October 25, 2007
    Applicant: TDK CORPORATION
    Inventors: Tatsuhiro Kobayashi, Takashi Kikukawa, Narutoshi Fukuzawa
  • Publication number: 20070247988
    Abstract: A method and apparatus for measuring the read stability of an optical disc are provided. Specifically, readout of the optical disc is repeated at each of at least two read laser beams powers being different from each other. A graph is drawn in which the inverses of the read powers are plotted on a horizontal axis and in which on a vertical axis is plotted the logarithm of a repeated readout number for each of the read powers. Here, the repeated readout number is the number of repetitions of the readout when a characteristic value for the number of repetitions of the readout varies and reaches a predetermined value. The read stability of the optical disc is evaluated by using the gradient of the graph.
    Type: Application
    Filed: April 20, 2007
    Publication date: October 25, 2007
    Applicant: TDK CORPORATION
    Inventors: Takashi Kikukawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi
  • Patent number: 7277852
    Abstract: A playlist generating method for generating a playlist of content from received broadcasted data is provided. The playlist generating method includes the steps of: extracting features of broadcast content beforehand, storing the features in a content feature file, and storing information relating to the broadcast content in a content information DB; extracting features from the received data, and storing the features in a data feature file; searching for broadcast content of a predetermined kind by comparing data in the content feature file and data in the data feature file; when a name of the predetermined kind of content is determined, storing data corresponding to the broadcast content of the predetermined kind in a search result file; generating a playlist for the broadcast content of the predetermined kind from the search result file and the content information DB.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: October 2, 2007
    Assignee: NTT Communications Corporation
    Inventors: Miwako Iyoku, Tatsuhiro Kobayashi
  • Publication number: 20070195673
    Abstract: A method for recording information on a super-resolution optical recording medium is directed to a reproducing laser beam which moves during the reproduction of the super-resolution optical recording medium from a recording mark/space train smaller than the resolution limit to a recording mark, or mark/space train larger than or equal to the resolution limit. A pulse train employed by the method for forming a recording mark larger than or equal to the resolution limit immediately after a smaller space than the resolution limit of a reproduction optical system includes at least a first ON pulse T1 of recording power followed by a first OFF pulse and second ON pulses T21 and T22 in that order. The first OFF pulse includes an OFF pulse Pc of cooling power and an OFF pulse Pm of middle power in that order.
    Type: Application
    Filed: February 13, 2007
    Publication date: August 23, 2007
    Applicant: TDK CORPORATION
    Inventors: Tatsuhiro Kobayashi, Takashi Kikukawa, Narutoshi Fukuzawa
  • Publication number: 20070183289
    Abstract: When a recording mark and a space, each having a size depending on a modulation code corresponding to information to be recorded, are formed in a super-resolution optical recording medium which has at least a substrate and a recording layer, a super-resolution layer, and a light transmitting layer on the substrate, a space shorter than at least the resolution limit of a reproducing optical system is formed so that the space has a crescent shape when plan view from top surface and a convex section when viewed in a direction normal to a track, thereby allowing high carrier-to-noise ratio (CNR) recording of information.
    Type: Application
    Filed: January 30, 2007
    Publication date: August 9, 2007
    Applicant: TDK CORPORATION
    Inventors: Narutoshi Fukuzawa, Takashi Kikukawa, Tatsuhiro Kobayashi
  • Publication number: 20070177473
    Abstract: A method of optimizing a writing condition of an optical recording medium, including writing test pattern data with the writing condition on the optical recording medium, comparing an error pattern binary signal detected by reproducing the written test pattern data with a correct pattern binary signal of the test pattern data, and determining an optimum writing condition of the optical recording medium based on a result of the comparison.
    Type: Application
    Filed: December 19, 2006
    Publication date: August 2, 2007
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Jae-cheol Bae, In-oh Hwang, Kyung-geun Lee, Hui Zhao, Narutoshi Fukuzawa, Takashi Kikukawa, Tatsuhiro Kobayashi
  • Publication number: 20070140083
    Abstract: A method of determining an optimum reproduction condition of a first mark recorded on an optical recording medium that is smaller than a resolution of a pickup to reproduce the first mark. The method includes obtaining an optimum reproduction condition of a second mark having a length which closely approximates the resolution of the pickup, and determining the optimum reproduction condition of the first mark using the obtained optimum reproduction condition of the second mark.
    Type: Application
    Filed: December 19, 2006
    Publication date: June 21, 2007
    Applicants: Sansung Electronics Co., Ltd., TDK Corporation
    Inventors: Jae-cheol Bae, Joo-ho Kim, In-oh Hwang, Hyun-soo Park, Narutoshi Fukuzawa, Takashi Kikukawa, Tatsuhiro Kobayashi
  • Publication number: 20070140094
    Abstract: An optical disk primarily includes a recording layer and a viscosity-variable material layer. When a laser beam is irradiated to reproduce a record written on the recording layer, part of the crystalline thin layer of the viscosity-variable material layer is softened to vary the optical constant of the softened region. Consequently, a plane having discontinuous optical constants is produced at the boundary between the softened region and the other region, so that a ring-shaped specific region is produced in a light spot. The ring-shaped specific region allows record patterns smaller than or equal to the resolution limit to be reproduced with the same signal intensity as that of the other record patterns larger than the resolution limit.
    Type: Application
    Filed: August 7, 2006
    Publication date: June 21, 2007
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Takayuki SHIMA, Junji TOMINAGA, Takashi NAKANO, Takashi KIKUKAWA, Narutoshi FUKUZAWA, Tatsuhiro KOBAYASHI, Joo-ho KIM, In-oh HWANG
  • Publication number: 20070140087
    Abstract: A super-resolution optical recording medium has at least a recording layer and a super resolution layer on a substrate. A recording mark with the size of a resolution limit or less and a space with the size of the resolution limit or less are formed in the super-resolution optical recording medium by adjusting the intensity of a laser for recording or an emission pattern of the laser for recording such that at least the recoding mark with the size of the resolution limit or less out of recording marks in a modulation code is formed into a concave section with respect to a not-recorded section.
    Type: Application
    Filed: December 8, 2006
    Publication date: June 21, 2007
    Applicant: TDK CORPORATION
    Inventors: Narutoshi Fukuzawa, Takashi Kikukawa, Tatsuhiro Kobayashi
  • Publication number: 20070098946
    Abstract: It is an object of the present invention to provide an optical recording disc which can record data constituted by a recording mark train including recording marks and blank regions neighboring recording marks therein and reproduce the data therefrom even in the case where the lengths of a recording mark and a blank region between neighboring recording marks are shorter than the resolution limit, thereby markedly increasing the storage capacity thereof and can improve a C/N ratio of a reproduced signal and the reproduction durability thereof.
    Type: Application
    Filed: June 30, 2004
    Publication date: May 3, 2007
    Applicant: TDK CORPORATION
    Inventors: Takashi Kikukawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi
  • Publication number: 20070081443
    Abstract: A super-resolution optical recording medium has at least a recording layer and a super resolution layer on a substrate. In the recording layer, a minimum recording mark is formed with spaces within a beam spot of a laser beam in recording. The minimum recording mark has a size of a resolution limit of a reproduction optical system or less, and can be reproduced by the reproduction optical system due to the existence of the super solution layer. The minimum recording mark in an AFM image takes the shape of a convex arc on a leading edge thereof and the shape of a concave arc on a trailing edge thereof (the AFM image is a plan view which can be observed on a surface when the light transmission layer is removed), and spaces have the similar shape to these.
    Type: Application
    Filed: October 3, 2006
    Publication date: April 12, 2007
    Applicant: TDK CORPORATION
    Inventors: Takashi Kikukawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi
  • Publication number: 20070064568
    Abstract: A method for recording information on an optical recording medium in which a laser beam modulated into one or a plurality of write pulses with one or a plurality of write powers in accordance with target data to be written is projected onto a recording layer of the optical recording medium to form a record mark. During recording the information on the optical recording medium, a data level and a weight index are assigned to each channel bit in reference data trains before and after the target data. Recording compensation of the target data is carried out in accordance with the sum totals of the products of the data level and the weight index in the reference data trains, so that it is possible to easily carry out high a real recording by writing fine mark/space trains.
    Type: Application
    Filed: September 18, 2006
    Publication date: March 22, 2007
    Applicant: TDK CORPORATION
    Inventors: Narutoshi Fukuzawa, Takashi Kikukawa, Tatsuhiro Kobayashi
  • Publication number: 20070030795
    Abstract: An optical recording medium 10 according to the present invention includes a supporting substrate 11 on which a groove 11a is formed, a light transmitting layer 12, a noble metal oxide layer 23 provided between the supporting substrate 11 and the light transmitting layer 12, wherein a depth of the groove 11a is set in excess of ?/8 n but 60 nm or less, where n is a refractive index of the light transmitting layer 12 with respect to a light whose wavelength is ?. Thus, the good signal characteristics, especially a push-pull signal with an enough amplitude, can be obtained when the super-resolution recording and super-resolution reading are carried out by irradiating the laser beam onto the noble metal oxide layer 23. Also, since the depth of the groove is set to 60 nm or less, a grave difficulty never arises in producing a stamper used to manufacture the substrate.
    Type: Application
    Filed: September 1, 2004
    Publication date: February 8, 2007
    Inventors: Takashi Kikuawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi
  • Publication number: 20070030776
    Abstract: A super-resolution information recording medium, a recording/reproducing apparatus, and a recording/reproducing method uses an information recording medium provides a super-resolution effect by fluid bubbles. The fluid bubbles are formed in at least a portion of the medium by a light beam radiated to reproduce a signal from the information recording medium. Accordingly, the super-resolution information recording medium has improved optical characteristics, so that better recording/reproduction is possible.
    Type: Application
    Filed: August 7, 2006
    Publication date: February 8, 2007
    Applicants: Samsung Electronics Co., Ltd., National Institute of Advanced Industrial Science and Technology
    Inventors: Joo-ho Kim, In-oh Hwang, Narutoshi Fukuzawa, Junji Tominaga, Takashi Kikukawa, Tatsuhiro Kobayashi, Takashi Nakano, Takayuki Shima
  • Publication number: 20060280895
    Abstract: An optical recording medium 10 is provided with a supporting substrate 11 and a light-transmitting layer 12, and further has between the light-transmitting layer 12 and the supporting substrate 11 a dielectric layer 31, a noble-metal oxide layer 23, a dielectric layer 32, a light absorption layer 22 and a dielectric layer 33. The second dielectric layer 32 contains as a main component ZnS or a mixture of ZnS and SiO2, and therein the proportion of ZnS to the sum of ZnS and SiO2 is set at a value from 60 mole % to 100 mole %. Since the material of the second dielectric layer 32 has both high hardness and elasticity, and high thermal conductivity besides, excellent balance of thermal conductivity with layer hardness can be achieved and makes it possible to form fine recording marks in true shapes.
    Type: Application
    Filed: August 12, 2004
    Publication date: December 14, 2006
    Applicant: TDK CORPORAION
    Inventors: Takashi Kikukawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi
  • Publication number: 20060280896
    Abstract: A supporting substrate 11 and a light-transmitting layer 12, and further between the light-transmitting layer and the supporting substrate 11 a dielectric layer 31, a noble metal oxide layer 23, a dielectric layer 32, a light absorption layer 22 and a dielectric layer 33 in this arranging order when viewed from the light-transmitting layer side are provided. The light absorption layer 22 contains as a main component a material that can be represented by (SbaTe1?a)1?bMAb (wherein MA is an element other than antimony (Sb) and tellurium (Te), 0<a<1 and 0?b<1), and besides, that is different from an intermetallic compound represented by {(GeTe)c(Sb2Te3)1?c)}dMB1?d (wherein MB is an element other than antimony (Sb), tellurium (Te) and germanium (Ge), c is ?, ½ or ?, and 0<d?1).
    Type: Application
    Filed: August 12, 2004
    Publication date: December 14, 2006
    Applicant: TDK Corp.
    Inventors: Takashi Kikukawa, Narutoshi Fukuzawa, Tatsuhiro Kobayashi