Patents by Inventor Yukio Takasaki

Yukio Takasaki 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: 5384597
    Abstract: An image pickup tube is provided with the third electrode to control the potential of the region which is not scanned by an electron beam in the image pickup tube target section including a target electrode and a photo-conductive film. A method for operating this image pickup tube is also disclosed. Thus, undesired image phenomena which are generated when the image pickup tube is used with a relatively high target voltage, e.g., image distortion, shading, a waterfall phenomenon and image inversion phenomenon can be suppressed, thereby realizing a high sensitivity image pickup tube.
    Type: Grant
    Filed: May 16, 1991
    Date of Patent: January 24, 1995
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Kenji Sameshima, Tatsuo Makishima, Tadaaki Hirai, Yukio Takasaki, Misao Kubota, Kenkichi Tanioka, Keiichi Shidara
  • Patent number: 5233265
    Abstract: A photoconductive device having a photoconductive layer which includes an amorphous semiconductor layer capable of charge multiplication in at least a part thereof is disclosed. The method of operating such a photoconductive device is also disclosed. By using the avalanche effect of the amorphous semiconductor layer, it is possible to realize a highly sensitive photoconductive device while maintaining low lag property. In one aspect of the present invention, the amorphous semiconductor layer is amorphous Se. In another aspect of the present invention, the amorphous semiconductor layer is composed mainly of tetrahedral elements including at least an element of hydrogen or halogens. When using the amorphous semiconductor layer composed mainly of tetrahedral elements, the charge multiplication effect is produced mainly in the interior of the amorphous semiconductor, and thus it is possible to obtain a thermally stable photoconductive device having a high sensitivity while keeping a good photoresponse.
    Type: Grant
    Filed: August 1, 1990
    Date of Patent: August 3, 1993
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Yukio Takasaki, Kazutaka Tsuji, Tatsuo Makishima, Tadaaki Hirai, Sachio Ishioka, Tatsuro Kawamura, Keiichi Shidara, Eikyu Hiruma, Kenkichi Tanioka, Junichi Yamazaki, Kenji Sameshima, Hirokazu Matsubara, Kazuhisa Taketoshi, Mitsuo Kosugi, Shiro Suzuki, Takashi Yamashita, Masaaki Aiba, Yoshizumi Ikeda, Tsuyoshi Uda, Naohiro Goto, Yasuhiko Nonaka, Eisuke Inoue, Hirofumi Ogawa
  • Patent number: 5218264
    Abstract: An image pick-up apparatus is disclosed which includes a target portion having a photoconductive film on a substrate and a target electrode and reads video information converted into an electric signal in the photoconductive film by an electron beam. An insulating region is provided for the target portion such that carrier generated in an ineffective scanned region (a target region corresponding to an area not scanned by the electron beam) does not appear on a surface of the target portion.
    Type: Grant
    Filed: January 31, 1990
    Date of Patent: June 8, 1993
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Tadaaki Hirai, Hirofumi Ogawa, Kenji Sameshima, Yukio Takasaki, Takaaki Unnai, Junichi Yamazaki, Misao Kubota, Kenkichi Tanioka, Eikyu Hiruma
  • Patent number: 5196702
    Abstract: An optically reading type photo-sensor for reading out an information signal of a signal light with a signal reading light includes a first photoconductor (101) and a second photoconductor (102) interposed between two electrodes (104 and 105); an intermediate region (103) disposed between those two photoconductors for storing and recombining carriers; and an optical source (107) for emitting a signal reading light for uninformalizing the potential in said second photoconductor (102), whereby a successive signal reading can be accomplished without any special preparations for the incidence of the signal light. The photo-sensor can be applied to a variety of imaging devices.
    Type: Grant
    Filed: December 11, 1991
    Date of Patent: March 23, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Kazutaka Tsuji, Tadaaki Hirai, Yukio Takasaki, Haruo Itoh, Tetshuhiko Takahashi, Kenichi Okajima
  • Patent number: 5101255
    Abstract: Disclosed is a photoelectric conversion device which comprises: a photoconductive layer made of amorphous semiconductor material which shows charge multiplication and which converts photo signals into electric signals; and a substrate having electric circuits or the like (for example switching elements) for reading the electric signals. The amorphous semiconductor material used according to the invention shows the charge multiplication action under predetermined intensity of electric field so that a high sensitive photoelectric conversion device having a gain which is not smaller than 1 is realized.
    Type: Grant
    Filed: July 24, 1989
    Date of Patent: March 31, 1992
    Inventors: Sachio Ishioka, Yukio Takasaki, Tadaaki Hirai, Kazutaka Tsuji, Tatsuo Makishima, Yasuhiko Nonaka, Tatsuro Kawamura, Takashi Yamashita, Kazuhisa Taketoshi, Keiichi Shidara, Fumihiko Ando, Kenkichi Tanioka
  • Patent number: 5023896
    Abstract: An X-ray television apparatus applies an X-ray to an object to be inspected, converts the X-ray projection image of the object into an optical image by a fluorescent screen or an X-ray image intensifier, picks up the optical image by a TV camera, displays the video signal obtained by a TV monitor for fluoroscopic monitoring, and records radiograph of the object by using the video signal. Avalanche multiplication is caused on the photoconductive layer of the image pick-up tube of the TV camera so as to enable monitoring or imaging with high sensitivity at a low X-ray dose rate.
    Type: Grant
    Filed: May 25, 1989
    Date of Patent: June 11, 1991
    Assignee: Hitachi-Medical Corporation
    Inventors: Hisatake Yokouchi, Yukio Takasaki, Tadaaki Hirai, Kouichi Koike, Masayuki Tsuneoka, Yoichi Onodera, Takakazu Funo
  • Patent number: 4980736
    Abstract: A photoelectric conversion device using an amorphous material composed mainly of tetrahedral elements including at least an element of hydrogen and halogens as semiconductor material is disclosed. When a strong electric field is applied to a layer formed by using this amorphous semiconductor, a charge multiplication effect is produced mainly in the interior of the amorphous semiconductor and thus it is possible to obtain a thermally stable photoelectric conversion device having a high sensitivity while keeping a good photoresponse.
    Type: Grant
    Filed: February 16, 1988
    Date of Patent: December 25, 1990
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Yukio Takasaki, Kazutaka Tsuji, Tatsuo Makishima, Tadaaki Hirai, Sachio Ishioka, Tatsuro Kawamura, Keiichi Shidara, Eikyu Hiruma, Kenkichi Tanioka, Junichi Yamazaki, Kenji Sameshima, Hirokazu Matsubara, Kazuhisa Taketoshi
  • Patent number: 4952839
    Abstract: A photoconductive device having a photoconductive layer which includes an amorphous semiconductor layer capable of charge multiplication in at least a part thereof is disclosed. The method of operating such a photoconductive device is also disclosed. By using the avalanche effect of the amorphous semiconductor layer, it is possible to realize a highly sensitive photoconductive device while maintaining low lag property.
    Type: Grant
    Filed: October 12, 1989
    Date of Patent: August 28, 1990
    Assignees: Hitachi, Ltd, Nippon Hoso Kyokai
    Inventors: Kenkichi Tanioka, Mitsuo Kosugi, Junichi Yamazaki, Keiichi Shidara, Kazuhisa Taketoshi, Tatsuro Kawamura, Eikyuu Hiruma, Shiro Suzuki, Takashi Yamashita, Masaaki Aiba, Yochizumi Ikeda, Tadaaki Hirai, Yukio Takasaki, Sachio Ishioka, Tatsuo Makishima, Kenji Sameshima, Tsuyoshi Uda, Naohiro Goto, Yasuhiko Nonaka, Eisuke Inoue, Kazutaka Tsuji, Hirofumi Ogawa
  • Patent number: 4900975
    Abstract: A target of an image pickup tube is formed by laminating at least a transparent conductive film, an amorphous layer consisting essentially of silicon, and an amorphous layer consisting essentially of selenium in the above order on a light-transmitting substrate.
    Type: Grant
    Filed: June 29, 1987
    Date of Patent: February 13, 1990
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Yasuharu Shimomoto, Sachio Ishioka, Yukio Takasaki, Tadaaki Hirai, Kazutaka Tsuji, Tatsuo Makishima, Hirokazu Matsubara, Kenji Sameshima, Junichi Yamazaki, Kenkichi Tanioka, Mitsuo Kosugi, Keiichi Shidara, Tatsuro Kawamura, Eikyuu Hiruma, Takashi Yamashita
  • Patent number: 4888521
    Abstract: A photoconductive device having a photoconductive layer which includes an amorphous semiconductor layer capable of charge multiplication in at least a part thereof is disclosed. The method of operating such a photoconductive device is also disclosed. By using the avalanche effect of the amorphous semiconductor layer, it is possible to realize a highly sensitive photoconductive device while maintaining low lag property.
    Type: Grant
    Filed: July 2, 1987
    Date of Patent: December 19, 1989
    Assignees: Hitachi Ltd., Nippon Hoso Kyokai
    Inventors: Kenkichi Tanioka, Keiichi Shidara, Tatsuro Kawamura, Junichi Yamazaki, Eikyuu Hiruma, Kazuhisa Taketoshi, Shiro Suzuki, Takashi Yamashita, Mitsuo Kosugi, Yochizumi Ikeda, Masaaki Aiba, Tadaaki Hirai, Yukio Takasaki, Sachio Ishioka, Tatsuo Makishima, Kenji Sameshima, Tsuyoshi Uda, Naohiro Goto, Yasuhiko Nonaka, Eisuke Inoue, Kazutaka Tsuji, Hirofumi Ogawa
  • Patent number: 4866332
    Abstract: A target of an image pickup tube, having a transparent substrate, a transparent conductive film, a p-type photoconductive film made mainly from amorphous Se, and an n-type conductive film capable of forming a rectifying contact at the interface with the p-type photoconductive film, using the rectifying contact as a reverse bias, characterized in that the p-type photoconductive film containing at least a region having more than 35%, and to 60% by weight of Te in the film thickness direction, and at least a region containing 0.005 to 5% by weight of at least a material capable of forming shallow levels in the amorphous Se in the film thickness direction, has good after-image characteristics even if operated at a high temperature.
    Type: Grant
    Filed: February 19, 1987
    Date of Patent: September 12, 1989
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Yukio Takasaki, Tatsuo Makishima, Kazutaka Tsuji, Tadaaki Hirai, Eisuke Inoue, Yasuhiko Nonaka, Naohiro Goto, Masanao Yamamoto, Keiichi Shidara, Kenkichi Tanioka, Takashi Yamashita, Tatsuro Kawamura, Eikyuu Hiruma, Shirou Suzuki, Masaaki Aiba
  • Patent number: 4860093
    Abstract: The present invention relates to a method and an apparatus for driving image pick-up tubes in, particular, a color television camera or the like having more than one image pick-up tube and in particular to a method and an apparatus for driving image pick-up tubes in which the potentials of the cathode electrodes of the respective image pick-up tubes are set to the same common potential, the potential of the target electrode of at least one of the image pick-up tubes is set substantially to earth potential, target drive potentials are individually applied to the target electrodes of the other image pick-up tubes, and the target potential of each image pick-up tube is set to a value near the earth potential, so that a high S/N ratio is obtained. The driving appartatus can be miniaturized and easily driven. According to the invention, a capacitor, such as a chip capcitor or the like, with a low withstanding voltage can be used in a first-stage amplifier to amplify the video signal from the target electrode.
    Type: Grant
    Filed: January 13, 1988
    Date of Patent: August 22, 1989
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Takashi Yamashita, Keiichi Shidara, Masaaki Aiba, Yukio Takasaki, Tadaaki Hirai
  • Patent number: 4829345
    Abstract: Within an electronic device having a plurality of circuit parts (such as a three-dimensional device), a light transmission system which transfers signals between the circuit parts by the use of light is provided.The light transmission system is formed of a light emitting source which emits light having a desired wavelength, a photoelectric conversion portion which absorbs the light and converts it into an electric signal, and a light traveling path which conveys the light emitted from the light emitting source to the photoelectric conversion portion.Further, each of the light emitting source, the light traveling path and the photoelectric conversion portion is formed of a superlattice structure in which a plurality of materials of unequal energy gaps are layered.
    Type: Grant
    Filed: April 29, 1986
    Date of Patent: May 9, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Sachio Ishioka, Kazutaka Tsuji, Yukio Takasaki, Yasuharu Shimomoto, Hirokazu Matsubara, Tadaaki Hirai
  • Patent number: 4636682
    Abstract: A high velocity electron beam scanning negatively charge biased image pickup tube has a target which includes at least a transparent conductive layer, a photoconductor layer and a layer for secondary electron emission on a light-transmissive insulating substrate, and in which the transparent conductive layer is arranged on a light incidence side, the photoconductor layer being made of amorphous silicon.
    Type: Grant
    Filed: May 5, 1983
    Date of Patent: January 13, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Chushirou Kusano, Sachio Ishioka, Yoshinori Imamura, Yukio Takasaki, Hirofumi Ogawa, Tatsuo Makishima, Tadaaki Hirai
  • Patent number: 4626885
    Abstract: A photosensor including a transparent electrode for transmitting incident light and a photoconductive layer receiving light from the transparent electrode for performing photoelectric conversion, is disclosed in which the photoconductive layer is made of amorphous silicon, the amorphous silicon contains 5 to 30 atomic percent hydrogen and is doped with at least one selected from elements belonging to the groups II and III in such a manner that a region remote from the transparent electrode is higher in the concentration of the selected element than another region proximate to the transparent electrode, and a voltage is applied across the photoconductive layer so that a surface of the photoconductive layer facing the transparent electrode is at a positive potential with respect to another surface of the photoconductive layer opposite to the surface facing the transparent electrode.
    Type: Grant
    Filed: July 29, 1983
    Date of Patent: December 2, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Sachio Ishioka, Yoshinori Imamura, Tsuyoshi Uda, Yukio Takasaki, Chushirou Kusano, Hirofumi Ogawa, Tatsuo Makishima, Tadaaki Hirai
  • Patent number: 4617248
    Abstract: A structure of a photoconductive film related to a target of an image pickup tube of the photo conductivity type is disclosed. This photoconductive film is formed from mainly Se and Te is added in a central part thereof. Further, As, which is considered to form a deep trap level which captures electrons in Se and GaF.sub.3, etc. which form negative space charges by capturing electrons in Se are added in the region adjacent to the region where Te exists. In addition, a thickness of film in the region where GaF.sub.3, etc. exists is selected to be thinner (not smaller than 20 .ANG. and not larger than 90 .ANG.) than a value which has been adopted so far.
    Type: Grant
    Filed: May 20, 1985
    Date of Patent: October 14, 1986
    Assignees: Nippon Hoso Kyokai, Hitachi, Ltd.
    Inventors: Kenkichi Tanioka, Keiichi Shidara, Takao Kuriyama, Yukio Takasaki, Tadaaki Hirai, Yasuhiko Nonaka, Eisuke Inoue
  • Patent number: 4556817
    Abstract: An image pickup tube of high velocity electron beam scanning and negatively charging system having a target including, on a transparent substrate, at least a transparent conductive film, a photoconductive layer, a layer for emitting secondary electrons, and stripe electrodes. The transparent substrate may be made of amorphous silicon.
    Type: Grant
    Filed: November 2, 1983
    Date of Patent: December 3, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Chushirou Kusano, Sachio Ishioka, Yoshinori Imamura, Yukio Takasaki, Hirofumi Ogawa, Tatsuo Makishima, Tadaaki Hirai, Eiichi Maruyama
  • Patent number: 4556816
    Abstract: Disclosed is a photoelectric device having at least a signal electrode, and an amorphous photoconductor layer whose principal constituent is silicon and which contains hydrogen as an indispensable constituent element, the amorphous photoconductor layer being disposed in adjacency to the signal electrode, characterized by comprising a thin layer interposed between the signal electrode and the amorphous photoconductor layer, the thin layer being made of an inorganic material whose principal constituent is at least one compound selected from the group consisting of oxides of at least one element selected from the group that consists of Si, Ti, Al, Mg, Ba, Ta, Bi, V, Ni, Th, Fe, La, Be, Sc and Co, nitrides of at least one element selected from the group that consists of Ga, Si, Mg, Te, Hf, Zr, Nb and B, and halides of at least one element selected from the group that consists of Na, Mg, Li, Ba, Ca and K.
    Type: Grant
    Filed: July 5, 1983
    Date of Patent: December 3, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Yoshinori Imamura, Saburo Ataka, Yukio Takasaki, Yasuo Tanaka, Tadaaki Hirai, Eiichi Maruyama
  • Patent number: 4554478
    Abstract: In a photoelectric conversion element including at least a first electrode and a photoconductive layer having an amorphous material whose indispensable constituent is silicon and which contains hydrogen as an essential constituent element on a predetermined substrate, the present invention discloses a photoelectric conversion element wherein said layer of the amorphous material is disposed on said first electrode via a light transmitting or light semi-transmitting metallic layer for adhesion with respect to said amorphous material. As said metallic layer for adhesion, preferred is a layer consisting of at least one metal selected from the group consisting of Ta, Cr, W, Nd, Mo, V and Ti. Thus, adhesion between said substrate and said amorphous material can be improved.
    Type: Grant
    Filed: May 25, 1983
    Date of Patent: November 19, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Yasuharu Shimomoto, Yasuo Tanaka, Yukio Takasaki, Sachio Ishioka, Toshihisa Tsukada, Toru Baji
  • Patent number: 4463279
    Abstract: A photoconductive film comprising a photo-conductive layer which is mainly made of selenium and a region added with tellurium in a direction of the thickness of the layer, wherein at least either one of a portion in a direction of hole flow of said region added with tellurium and a portion in the hole flow of another region which is located adjacent to said region added with tellurium is doped with at least one member selected from the group consisting of an oxide, a fluoride and elements which belong to the group II, III and VII, which are capable of forming a negative space charge in selenium, at a concentration in a range of 10 ppm to 1% by weight on an average. Typical examples of such oxide, fluoride and element include CuO, In.sub.2 O.sub.3, SeO.sub.2, V.sub.2 O.sub.5, MoO.sub.3, WO.sub.3, GaF.sub.2 InF.sub.3, Zn, Ga, In, Cl, I, Br and the like. The after image characteristic ascribable to incident light of high intensity can be significantly improved.
    Type: Grant
    Filed: May 21, 1982
    Date of Patent: July 31, 1984
    Assignees: Hitachi, Ltd., Nippon Hoso Kyokai
    Inventors: Keiichi Shidara, Kenkichi Tanioka, Teruo Uchida, Chushirou Kusano, Yukio Takasaki, Yasuhiko Nonaka, Eisuke Inoue