Patents by Inventor Hideaki Oba

Hideaki Oba 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).

  • Publication number: 20100014394
    Abstract: A recording method including: recording on a write-once-read-many optical medium capable of recording and reproducing with a blue laser by CAV, ZCLV, or PCAV, wherein a laser emission pattern including a recording pulse comprises two or more different levels of recording power, and a laser emission time standardized by the laser emission pattern and reference clock is fixed regardless of a recording linear velocity.
    Type: Application
    Filed: August 30, 2007
    Publication date: January 21, 2010
    Applicant: RICOH COMPANY, LTD.
    Inventors: Masayuki Fujiwara, Noboru Sasa, Yoshitaka Hayashi, Toshishige Fujii, Katsuyuki Yamada, Masaki Kato, Shinya Narumi, Hideaki Oba, Hiroyoshi Sekiguchi, Toshihide Sasaki
  • Patent number: 4891305
    Abstract: This invention relate to an optical information recording medium, characterized by having an organic thin film recording layer containing at least one of compounds expressed by the general formula (I), (II), (III) and (IV): ##STR1## (wherein in the above formulas, A, B, D and E represent a substituted or non-substituted aryl group; R.sub.1 to R.sub.8 may be the same or different and represent hydrogen atom, halogen atom or alkyl group; Y represents a divalent residue having atomic groups necessary for forming a five-membered ring or six-membered ring; m, n and l represents 0, 1 or 2; ans X.sup.
    Type: Grant
    Filed: July 7, 1988
    Date of Patent: January 2, 1990
    Assignee: Ricoh Co., Ltd.
    Inventors: Hideaki Oba, Tsutomu Sato, Masaakira Umehara, Yutaka Ueda, Tetsu Yamamuro, Michiharu Abe
  • Patent number: 4767693
    Abstract: This invention provides an optical information recording medium that has, on a substrate, a recording layer containing a cyanine dye represented by the general formula: ##STR1## (wherein, R.sub.1, R.sub.2 and R.sub.3 may be the same or different and each stands for a substituted or unsubstituted alkyl group; X stands for a perhalogenate ion, a toluenesulfonate ion or an alkylsulfate ion; n stands for an integrer of 0 or 1-3; a first halogen atom is present in at least one of each 4, 6 and 7-positions of the indole and indolenine rings; a second halogen atom may be present in each 5-position of said rings; and at lest one group consisting of alkyl, alkoxy, hydroxy, carboxy, allyl and alkylcarbonyl may be present in at least one of each 4, 5, 6 and 7-positions of said rings.) and, if necessary, a transition metal complex or a salt of said complex with a cation.
    Type: Grant
    Filed: October 2, 1987
    Date of Patent: August 30, 1988
    Assignee: Ricoh Co., Ltd.
    Inventors: Hideaki Oba, Yutaka Ueda, Tsutomu Sato, Masaakira Umehara, Michiharu Abe, Hitoshi Funakoshi, Seiko Kobayashi
  • Patent number: 4758499
    Abstract: This invention relates to an optical information recording medium, characterized by having an organic thin film recording layer containing at least one of triaryl methane type coloring matters expressed by the general formula (1), (2) or (3): ##STR1## (wherein, in the above formulas (1) and (2), Ar.sub.1, Ar.sub.2 and Ar.sub.3 may be the same or different and represent a substituted or non-substituted arylene group, at least one pair of optical two nitrogen atoms bonded with said arylene groups being connected by an atomic chain having at least ten carbon atoms in total number in the shortest way; R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6 and R.sub.
    Type: Grant
    Filed: September 5, 1986
    Date of Patent: July 19, 1988
    Assignee: Ricoh Co., Ltd.
    Inventors: Michiharu Abe, Tsutomu Sato, Hideaki Oba, Masaakira Umehara, Yutaka Ueda, Tetsu Yamamuro
  • Patent number: 4752554
    Abstract: The present invention relates to an optical information recording medium comprising a substrate, recording layer and protective layer, characterized in that said protective layer comprises, as the main components, a high molecular compound and at least one of record-promoting agents selected from the group of (a) explosive material, (b) plasticizer, (c) organic low molecular compound having a melting point not higher than 140.degree. C., and (d) light-absorbing material.
    Type: Grant
    Filed: June 2, 1986
    Date of Patent: June 21, 1988
    Assignee: Ricoh Co., Ltd.
    Inventors: Tsutomu Sato, Hideaki Oba
  • Patent number: 4714667
    Abstract: The present invention relates to an optical information recording medium comprising a recording layer applied directly on a substrate or applied on a substrate by intervening an underlayer therebetween, and further comprising a protective layer on said recording layer if necessary, characterized in that said recording layer contains at least one of the compounds expressed by the following general formula (I) or (II): ##STR1## (wherein in the above formulas, X.sub.1 to X.sub.3 represent O, S or Se; A.sup.- represents an anion; l, m or n represents 0 or 1; R.sub.4 represents a substituted or non-substituted aryl group or heterocyclic group; R.sub.3, R.sub.5, R.sub.6, R.sub.9, R.sub.10 and R.sub.11 represent hydrogen or an alkyl group; R.sub.1, R.sub.2, R.sub.7, R.sub.8, R.sub.12, and R.sub.13 represent hydrogen or a substituted or non-substituted alkyl, aryl or styryl group; Z.sub.1, Z.sub.3 and Z.sub.
    Type: Grant
    Filed: December 12, 1985
    Date of Patent: December 22, 1987
    Assignee: Ricoh Co., Ltd.
    Inventors: Tsutomu Sato, Masaakira Umehara, Michiharu Abe, Hideaki Oba, Yutaka Ueda
  • Patent number: 4696892
    Abstract: This invention relates to an optical information recording medium, characterized in that on a substrate there is applied a coloring matter film chemically inert to said substrate, said coloring matter film having an extinction coefficient of at least 1.
    Type: Grant
    Filed: February 27, 1985
    Date of Patent: September 29, 1987
    Assignee: Ricoh Co., Ltd.
    Inventors: Michiharu Abe, Masaakira Umehara, Tsutomu Sato, Hideaki Oba, Yutaka Ueda, Makoto Kunikane
  • Patent number: 4656121
    Abstract: This invention relates to an optical information recording medium having an organic thin film recording layer, and optionally having an underlayer and/or protective layer, characterized in that at least one of said recording layer, underlayer and protective layer contains a compound expressed by the general formula (1), ##STR1## wherein R represents hydrogen or a lower alkyl group; X represents acid anion; m represents 0, 1 or 2; and A represents ##STR2## (n being 1 or 2) or ##STR3## (when m is 2); all the aromatic rings optionally having a substituent selected from the group of a lower alkyl group, lower alkoxy group, halogen and hydroxyl group.
    Type: Grant
    Filed: February 6, 1985
    Date of Patent: April 7, 1987
    Assignee: Ricoh Co., Ltd.
    Inventors: Tsutomu Sato, Masaakira Umehara, Michiharu Abe, Hideaki Oba, Yutaka Ueda
  • Patent number: 4652514
    Abstract: An optical information recording medium which comprises the provision of a thin film (recording layer) formed of a cyanine coloring matter and a transition metal complex being superior in long wavelength range light absorbability to said coloring matter on a transparent or opaque substrate and which permits writing and reading by using laser beam.
    Type: Grant
    Filed: September 20, 1984
    Date of Patent: March 24, 1987
    Assignee: Ricoh Co., Ltd.
    Inventors: Michiharu Abe, Hideaki Oba
  • Patent number: 4600625
    Abstract: An optical information recording medium being capable of writing and reading with laser beam which comprises forming, on a transparent or opaque substrate, a thin film (recording layer) containing a cyanine coloring matter represented by the general formula: ##STR1## (wherein, R.sup.1, R.sup.2 and R.sup.3 may be the same or different, and each stands for C.sub.1 -C.sub.6 alkyl; X stands for halogen, perhalogenate, boron tetrafluoride, toluenesulfonic acid or alkylsulfonic acid; A stands for a benzene ring or a naphthyl ring and a substituent such as alkyl, alkoxy, hydroxy, carboxyl, halogen, allyl or alkylcarboxyl may be or may be not present on each ring; and n is an integer of 1-3.).
    Type: Grant
    Filed: September 18, 1984
    Date of Patent: July 15, 1986
    Assignee: Ricoh Co., Ltd.
    Inventors: Michiharu Abe, Hideaki Oba
  • Patent number: 4477555
    Abstract: An optical information recording medium comprising a substrate and a recording layer superimposed on said substrate, said recording layer comprising a reflective layer in which metal particles with a particle diameter of 1500.ANG. or less have been distributed closely and a light absorptive layer in which metal compounds and a very small amount of metal particles with a particle diameter of 200-2000.ANG. have been dispersed unformly or substantially uniformly in the volume ratio of 1-30% in a resin.
    Type: Grant
    Filed: July 28, 1982
    Date of Patent: October 16, 1984
    Assignee: Ricoh Co., Ltd.
    Inventors: Hideaki Oba, Makoto Kunikane, Masaakira Umehara, Kiyoshi Tanikawa, Michiharu Abe
  • Patent number: 4465767
    Abstract: An optical information recording medium comprising a substrate and a recording layer superimposed on said substrate, said recording layer being comprised of a reflective layer which contains metal particles having a particle diameter of 1500 .ANG. or less and in which said metal particles have been distributed closely and a light absorptive layer containing a coloring matter.
    Type: Grant
    Filed: September 27, 1982
    Date of Patent: August 14, 1984
    Assignee: Ricoh Company, Ltd.
    Inventors: Hideaki Oba, Masaakira Umehara