Patents by Inventor Yasuhiro Okamoto

Yasuhiro Okamoto 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: 20140353720
    Abstract: To provide a semiconductor device having improved characteristics. The semiconductor device has a substrate and thereon a buffer layer, a channel layer, a barrier layer, a trench penetrating therethrough and reaching the inside of the channel layer, a gate electrode placed in the trench via a gate insulating film, and drain and source electrodes on the barrier layer on both sides of the gate electrode. The gate insulating film has a first portion made of a first insulating film and extending from the end portion of the trench to the side of the drain electrode and a second portion made of first and second insulating films and placed on the side of the drain electrode relative to the first portion. The on resistance can be reduced by decreasing the thickness of the first portion at the end portion of the trench on the side of the drain electrode.
    Type: Application
    Filed: May 6, 2014
    Publication date: December 4, 2014
    Applicant: Renesas Electronics Corporation
    Inventors: Takashi Inoue, Tatsuo Nakayama, Yasuhiro Okamoto, Hiroshi Kawaguchi, Toshiyuki Takewaki, Nobuhiro Nagura, Takayuki Nagai, Yoshinao Miura, Hironobu Miyamoto
  • Patent number: 8888685
    Abstract: A medical system includes: an endoscope including an insertion portion that can be inserted into a body cavity of a subject, and an image pickup section provided at a distal end portion of the insertion portion; an exclusion section capable of, when the insertion portion is inserted into the body cavity of the subject, excluding a tissue existing around the distal end portion; a computing section that obtains luminance information relating to a luminance of an image picked up by the image pickup section, and determines whether or not the obtained luminance information meets a predetermined condition; a drive section that if a determination result that the luminance information does not meet the predetermined condition is provided, continues an operation to drive the exclusion section, and if a determination result that the luminance information meets the predetermined condition is provided, stops the operation to drive the exclusion section.
    Type: Grant
    Filed: July 19, 2013
    Date of Patent: November 18, 2014
    Assignee: Olympus Medical Systems Corp.
    Inventors: Yoshitaka Umemoto, Yasuhiro Okamoto
  • Publication number: 20140315024
    Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of the particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. One of specifically disclosed is a method of producing a substantially rectangular cuboid particulate alkali metal niobate represented by MNbO3 (1), wherein M represents one element selected from alkaline metals, including specific four steps. Another one of specifically disclosed is particulate alkali metal niobate represented by the formula (1) having a substantially rectangular cuboid shape, wherein the substantially rectangular cuboid shape has a longest side and a shortest side, the length of the longest side represented by an index Lmax is 0.10 to 25 ?m, and the length of the shortest side represented by an index Lmin is 0.050 to 15 ?m.
    Type: Application
    Filed: February 27, 2014
    Publication date: October 23, 2014
    Applicants: Sakai Chemical Industry Co., Ltd., Fuji Ceramics Corporation, TOHOKU University
    Inventors: Atsushi MURAMATSU, Kiyoshi KANIE, Atsuki TERABE, Yasuhiro OKAMOTO, Hideto MIZUTANI, Satoru SUEDA, Hirofumi TAKAHASHI
  • Publication number: 20140309625
    Abstract: An insertion apparatus according to an aspect of the present invention includes: an insertion portion to be inserted into a subject; a bending operation apparatus to be moved by an operator to input an operation instruction; a bending drive section that generates a drive force based on the movement of the bending operation apparatus; a pulling member to be pulled by the drive force from the bending drive section; a bending portion provided in the insertion portion, the bending portion being connected to the pulling member and being bent upon the pulling member being pulled; and a haptic section that connects the pulling member and the bending operation apparatus via an elastic portion.
    Type: Application
    Filed: May 20, 2014
    Publication date: October 16, 2014
    Applicant: OLYMPUS MEDICAL SYSTEMS CORP.
    Inventors: Yasuhiro OKAMOTO, Hiroki MORIYAMA, Hiroaki MIYOSHI, Yutaka MASAKI
  • Publication number: 20140298932
    Abstract: An endoscope apparatus includes: an insertion portion; an insertion assisting mechanism portion that is provided on an outer circumference of the insertion portion and is rotatable in a first rotational direction, or a second rotational direction that is the opposite direction to the first rotational direction; a drive portion that generates a driving force for causing the insertion assisting mechanism portion to rotate; a drive shaft that can be rotated by a driving force of the drive portion, and with respect to which a torsional rigidity in a fourth rotational direction that is an opposite direction to a third rotational direction is set so as to be higher than a torsional rigidity in the third rotational direction; and a drive mechanism portion that, by means of the drive shaft rotating in the fourth rotational direction, causes the insertion assisting mechanism portion to rotate in the first rotational direction.
    Type: Application
    Filed: May 14, 2014
    Publication date: October 9, 2014
    Applicant: OLYMPUS MEDICAL SYSTEMS CORP.
    Inventor: Yasuhiro OKAMOTO
  • Patent number: 8853666
    Abstract: In a group III nitride-type field effect transistor, the present invention reduces a leak current component by conduction of residual carriers in a buffer layer, and achieves improvement in a break-down voltage, and enhances a carrier confinement effect (carrier confinement) of a channel to improve pinch-off characteristics (to suppress a short channel effect). For example, when applying the present invention to a GaN-type field effect transistor, besides GaN of a channel layer, a composition-modulated (composition-gradient) AlGaN layer in which aluminum composition reduces toward a top gradually or stepwise is used as a buffer layer (hetero buffer).
    Type: Grant
    Filed: October 25, 2006
    Date of Patent: October 7, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Takashi Inoue, Tatsuo Nakayama, Yuji Ando, Yasuhiro Murase, Kazuki Ota, Hironobu Miyamoto, Katsumi Yamanoguchi, Naotaka Kuroda, Akio Wakejima, Yasuhiro Okamoto
  • Publication number: 20140264274
    Abstract: To improve performance of a semiconductor device. For example, on the assumption that a superlattice layer is inserted between a buffer layer and a channel layer, a concentration of acceptors introduced into nitride semiconductor layers forming a part of the superlattice layer is higher than a concentration of acceptors introduced into nitride semiconductor layers forming the other part of the superlattice layer. That is, the concentration of acceptors introduced into the nitride semiconductor layers having a small band gap is higher than the concentration of acceptors introduced into the nitride semiconductor layers having a large band gap.
    Type: Application
    Filed: March 5, 2014
    Publication date: September 18, 2014
    Applicant: Renesas Electronics Corporation
    Inventors: Tatsuo NAKAYAMA, Hironobu MIYAMOTO, Yasuhiro OKAMOTO, Ryohei NEGA, Masaaki KANAZAWA, Takashi INOUE
  • Publication number: 20140239311
    Abstract: A semiconductor device includes a buffer layer, a channel layer and a barrier layer formed over a substrate, a trench penetrating through the barrier layer to reach the middle of the channel layer, and a gate electrode disposed inside the trench via a gate insulating film. The channel layer contains n-type impurities, and a region of the channel layer positioned on a buffer layer side has an n-type impurity concentration larger than a region of the channel layer positioned on a barrier layer side, and the buffer layer is made of nitride semiconductor having a band gap wider than that of the channel layer. The channel layer is made of GaN and the buffer layer is made of AlGaN. The channel layer has a channel lower layer containing n-type impurities at an intermediate concentration and a main channel layer formed thereon and containing n-type impurities at a low concentration.
    Type: Application
    Filed: February 24, 2014
    Publication date: August 28, 2014
    Applicant: Renesas Electronics Corporation
    Inventors: Tohru Kawai, Takashi Inoue, Tatsuo Nakayama, Yasuhiro Okamoto, Hironobu Miyamoto
  • Publication number: 20140209980
    Abstract: A method for manufacturing a semiconductor device includes forming a buffer layer made of a nitride semiconductor, forming a channel layer made of a nitride semiconductor over the buffer layer, forming a barrier layer made of a nitride semiconductor over the channel layer, forming a cap layer made of a nitride semiconductor over the barrier layer, forming a gate insulating film so as to in contact with the cap layer; and forming a gate electrode over the gate insulating film, wherein compression strains are generated at an interface between the cap layer and the barrier layer and an interface between the channel layer and the buffer layer and a tensile strain is generated at an interface between the barrier layer and the channel layer by controlling compositions of the cap layer, the barrier layer, the channel layer, and the buffer layer.
    Type: Application
    Filed: March 28, 2014
    Publication date: July 31, 2014
    Applicant: Renesas Electronics Corporation
    Inventors: Takashi INOUE, Tatsuo NAKAYAMA, Yasuhiro OKAMOTO, Hironobu MIYAMOTO
  • Publication number: 20140190305
    Abstract: An introducing device system includes: an insertion portion; a bending portion which is provided at the insertion portion; an operation portion through which an input operation is performed for bending the bending portion; a pulling member connected to the bending portion and pulled in accordance with the operation through the operation portion; a detection section that detects a moving state of the pulling member; a driving unit that rotationally drives; a driving force transmitting unit including an inner circumferential surface configured to be able to contact an outer circumferential surface of the driving unit, and an outer circumference on which the pulling member is wound, the driving force transmitting unit being reduced in diameter in accordance with pulling of the pulling member; and a driving unit control section controls the driving unit when the moving state detected by the detection section is different from a state determined in advance.
    Type: Application
    Filed: January 29, 2014
    Publication date: July 10, 2014
    Applicant: OLYMPUS MEDICAL SYSTEMS CORP.
    Inventor: Yasuhiro OKAMOTO
  • Patent number: 8772785
    Abstract: A semiconductor device includes semiconductor layers, an anode electrode, and a cathode electrode. The semiconductor layers include a composition change layer, the anode electrode is electrically connected to one of principal surfaces of the composition change layer through a formation of a Schottky junction between the anode electrode and a part of the semiconductor layers, the cathode electrode is electrically connected to the other of the principal surfaces of the composition change layer through a formation of a junction between the cathode electrode and another part of the semiconductor layers, the anode electrode and the cathode electrode are capable of applying a voltage to the composition change layer in a direction perpendicular to the principal surface.
    Type: Grant
    Filed: November 26, 2009
    Date of Patent: July 8, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Yasuhiro Okamoto, Hironobu Miyamoto, Yuji Ando, Tatsuo Nakayama, Takashi Inoue, Kazuki Ota, Kazuomi Endo
  • Patent number: 8771618
    Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of the particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. One of specifically disclosed is a method of producing a substantially rectangular cuboid particulate alkali metal niobate represented by MNbO3 (1), wherein M represents one element selected from alkaline metals, including specific four steps. Another one of specifically disclosed is particulate alkali metal niobate represented by the formula (1) having a substantially rectangular cuboid shape, wherein the substantially rectangular cuboid shape has a longest side and a shortest side, the length of the longest side represented by an index Lmax is 0.10 to 25 ?m, and the length of the shortest side represented by an index Lmin is 0.050 to 15 ?m.
    Type: Grant
    Filed: April 5, 2010
    Date of Patent: July 8, 2014
    Assignees: Sakai Chemical Industry Co., Ltd., TOHOKU University, Fuji Ceramics Corporation
    Inventors: Atsushi Muramatsu, Kiyoshi Kanie, Atsuki Terabe, Yasuhiro Okamoto, Hideto Mizutani, Satoru Sueda, Hirofumi Takahashi
  • Publication number: 20140180008
    Abstract: An insertion portion, a function portion, an operation portion, a universal cord, a connection connector, a drive member that generates a drive force for causing the function portion to act, a connection portion that is provided at the connection connector and has the drive member connected thereto, and a drive force transmitting member that is inserted through the universal cord, and transmits the drive force generated by the drive member connected to the connection portion to the function portion are included.
    Type: Application
    Filed: January 10, 2014
    Publication date: June 26, 2014
    Applicant: OLYMPUS MEDICAL SYSTEMS CORP.
    Inventor: Yasuhiro OKAMOTO
  • Publication number: 20140171741
    Abstract: An insertion portion, a bending portion, a joystick, a pulling wire, a pulley, a C-shaped ring, and an end portion of a cutout portion that is provided at the C-shaped ring, and removes wear debris that is scraped from the pulley with contact of the C-shaped ring to the pulley from the pulley are provided.
    Type: Application
    Filed: January 28, 2014
    Publication date: June 19, 2014
    Applicant: OLYMPUS MEDICAL SYSTEMS CORP.
    Inventor: Yasuhiro OKAMOTO
  • Publication number: 20140135580
    Abstract: An insertion device sets engage range which it prescribed in return power to the neutral position by elastic force of the spring and rotation resistance force by the slide power by elastic member for dial portion performing curving operation of a curving portion. If a rotary angle is beyond an engage range, the dial part lets a rotary point of view to order return in an engage range and, if there is a rotary angle in an engage range, the dial part keeps a target part in an observation field of vision.
    Type: Application
    Filed: October 23, 2013
    Publication date: May 15, 2014
    Applicant: OLYMPUS MEDICAL SYSTEMS CORP.
    Inventors: Keijiro OMOTO, Hiroki MORIYAMA, Yasuhiro OKAMOTO
  • Patent number: 8716835
    Abstract: A bipolar transistor is provided with an emitter layer, a base layer and a collector layer. The emitter layer is formed above a substrate and is an n-type conductive layer including a first nitride semiconductor. The base layer is formed on the emitter layer and is a p-type conductive including a second nitride semiconductor. The collector layer is formed on the base layer and includes a third nitride semiconductor. The collector layer, the base layer and the emitter layer are formed such that a crystal growth direction to the substrate surface is parallel to a substrate direction of [000-1]. The third nitride semiconductor contains InycAlxcGa1-xc-ycN (0•xc•1, 0•yc•1, 0<xc+yc•1). The a-axis length on the side of a surface in the third nitride semiconductor is shorter than the a-axis length on the side of the substrate.
    Type: Grant
    Filed: October 16, 2009
    Date of Patent: May 6, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Yuji Ando, Hironobu Miyamoto, Tatsuo Nakayama, Yasuhiro Okamoto, Takashi Inoue, Kazuki Ota
  • Patent number: 8716755
    Abstract: Compression strains are generated at an interface between the cap layer and the barrier layer and an interface between the channel layer and the buffer layer and a tensile strain is generated at an interface between the barrier layer and the channel layer. Therefore, negative charge is higher than positive charge at the interface between the cap layer and the barrier layer and the interface between the channel layer and the buffer layer, while positive charge is higher than negative charge at the interface between the barrier layer and the channel. The channel layer has a stacked layer structure of a first layer, a second layer, and a third layer. The second layer has a higher electron affinity than those of the first layer and the third layer.
    Type: Grant
    Filed: July 19, 2012
    Date of Patent: May 6, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Takashi Inoue, Tatsuo Nakayama, Yasuhiro Okamoto, Hironobu Miyamoto
  • Publication number: 20140121462
    Abstract: The endoscope includes a drive section which bends and drives a bending portion, a C ring-shaped member which frictionally engages with a pulley and has a notch portion at a portion, an operation input member which performs bending operation, an operation input-side pulling member which is wound around the C ring-shaped member and extending toward the operation input member and is coupled to the operation input member such that a wrap distance, over which the operation input-side pulling member wraps around the C ring-shaped member across the notch portion, decreases with increase in the amount of operation of the operation input member, and a bending portion-side pulling member which is wound around the C ring-shaped member and extending toward the bending portion and is coupled to the bending portion so as not to wrap around the C ring-shaped member across the notch portion.
    Type: Application
    Filed: October 25, 2013
    Publication date: May 1, 2014
    Applicant: OLYMPUS MEDICAL SYSTEMS CORP.
    Inventor: Yasuhiro OKAMOTO
  • Publication number: 20140103246
    Abstract: Disclosed are a method of producing fine particulate alkali metal niobate in a liquid phase system, wherein the size and shape of particles of the fine particulate alkali metal niobate can be controlled; and fine particulate alkali metal niobate having a controlled shape and size. Specifically disclosed are a method of producing particulate sodium-potassium niobate represented by the formula (1): NaxK(1-x)NbO3 (1), the method including four specific steps, wherein a high-concentration alkaline solution containing Na+ ion and K+ ion is used as an alkaline solution; and particulate sodium-potassium niobate having a controlled shape and size.
    Type: Application
    Filed: December 19, 2013
    Publication date: April 17, 2014
    Applicants: Sakai Chemical Industry Co., Ltd., Fuji Ceramics Corporation, TOHOKU University
    Inventors: Atsushi MURAMATSU, Kiyoshi KANIE, Atsuki TERABE, Yasuhiro OKAMOTO, Hideto MIZUTANI, Satoru SUEDA, Hirofumi TAKAHASHI
  • Publication number: 20140084300
    Abstract: A field effect transistor includes a substrate and a semiconductor layer provided on the substrate, wherein the semiconductor layer includes a lower barrier layer provided on the substrate, Ga-face grown, lattice relaxed, and having a composition In1-zAlzN (0?z?1), a channel layer having a composition of: AlxGa1-xN (0?x?1) or InyGa1-yN (0?y?1). Or GaN provided on and lattice-matched to the lower barrier layer, a source electrode and a drain electrode having ohmic contact to an upper part of the semiconductor layers, disposed spaced to each other, and a gate electrode arranged via a gate insulating film in a region lying between the source electrode and the drain electrode.
    Type: Application
    Filed: May 15, 2012
    Publication date: March 27, 2014
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventors: Yasuhiro Okamoto, Yuji Ando, Tatsuo Nakayama, Takashi Inoue, Kazuki Ota