Olympus Optical Company, Ltd.

Kabushiki Kaisha Toshiba

Mitsubishi Denki Kabushiki Kaisha

Olympus Corporation

Oki Electric Industry Co., Ltd.

Kureha Corporation

Konica Minolta, Inc.

Nordson Corporation

Jx Nippon Oil Energy Corporation

Toshiba Corporation

Nippon Oil Corporation

Cosmo Oil Co., Ltd.

Japan Oil, Gas and Metals National Corporation

Fujitsu Toshiba Mobile Communications Limited

Japan Petroleum Exploration Co., Ltd.

Shinya Takahashi

Yasuo Asakura

Ryohei Sugihara

Satoru Furuta

Akira Tanaka

Tamotsu Koiwai

Yukihiko Sugita

Tatsuya Suzuki

Yoichi Iba

Takashi Honda

Keita Takahashi

Hiroyuki Tokimatsu

Shigeru Kato

Hirohisa Tasaki

Kuniyoshi Marui

Kiyoshi Hattori

Minoru Hara

Shinichi Mihara

Satoshi Miyazaki

Koji Kato

Sumio Kawai

Akira Watanabe

Takeshi Kamigaichi

Takaaki Ishii

Takayuki Tanaka

Takeo Takahashi

Takahiro Amanai

Yuichi Tanaka

Yoshinori Matsuzawa

Hiroshi Terada

Akihiko Hashimoto

Tatsuo Takanashi

Masatoshi Ida

Tatsuo Izumi

Tadashi Yamaura

Kazuyuki Iwasa

Toshifumi Nakano

Masayuki Okura

Munehisa Tomioka

Masami Takase

Nobuyuki Tanaka

Ikuo Kajiyama

Shinnosuke Yoshida

Yuki Hashimoto

Akira Inoue

Kunio Yokoyama

Mitsuhiro Sato

Bunkei Matsuoka

Masaki Nagao

Naohiro Tsuchida

Takaaki Ue

Mitsuru Obata

Kazuhiko Tasaka

Akiyoshi Tochigi

Marie Iwama

Hideshi Iki

Youji Watanabe

Shigeto Hatanaka

Shunji Matsutani

Masaki Tokui

Takashi Sakagawa

Mitsuo Kawazoe

Hitoshi Yoshida

Hidenori Uehara

Yoshiyuki Kitahara

Akira Katoh

Akiko Fujisawa

Masahiro Dai

Eitaro Morita

Kazuya Tsukamoto

Yoshito Kobayashi

Wang Wan

Tadahiro Omata

Toshiharu Watanabe

Hitoshi Takahashi

Tadashi Ushiyama

Kiyoshi Doi

Yoshiharu Asaoka

Aki Shitsukawa

Makoto Oishi

Kouichi Shijima

Yoshihito Bando

Provided is a frac plug or the like capable of being inserted into a borehole to seal the borehole with high strength, and then quickly disassembled and removed, thereby efficiently producing petroleum. A frac plug according to the present embodiment has a member made of a magnesium (Mg) alloy. The member has a multi-phase structure including a first phase, which is a matrix phase, and a second phase present in the first phase. In the multi-phase structure, the second phase is distributed in a substantially striped pattern in the first phase in a first cross section perpendicular to a second direction of the frac plug, and distributed in a substantially mesh-like pattern in the first phase in a second cross section perpendicular to a first direction of the frac plug.

Frac plug and method for manufacturing same, and method for sealing borehole

A downhole tool securing device and a frac plug which are excellent in setting properties and water pressure resistance and have excellent fracturing properties. A downhole tool securing device (slips) of a frac plug according to one embodiment of the present invention includes a button containing a powder metallurgy material and having a compressive elastic modulus of at least 13.5 GPa and a toughness of 0.23 GJ/mor greater and 1.0 GJ/mor less.

Downhole tool securing device and frac plug

In a dart for a downhole device according to the present invention, a ball is formed of a first degradable material having a first degradation rate, a mandrel is formed of a second degradable material having a second degradation rate lower than the first degradation rate, and a sleeve is formed of the second degradable material or a third degradable material having a third degradation rate lower than the second degradation rate.

Dart for downhole device and downhole device

A downhole plug for well completion is provided, which rapidly degrades after hydraulic fracturing, so that the flow path is recovered in a short time. A downhole plug () is provided, which includes: a mandrel () made of a degradable material; and a plurality of peripheral members () made of a degradable material and disposed on an outer peripheral surface of the mandrel (), where at least one of the plurality of peripheral members () includes: a hollow portion () through which a fluid flowing along an axial direction of the mandrel () can pass; or a groove in at least a portion of, a surface serving as an outer surface of the downhole plug (), or a surface in contact with the mandrel ().

Degradable downhole plug

A head-mounted display device is provided, the head-mounted display device including: a display element; a light guide prism that includes an incident surface through which image light from the display element enters and that guides the image light to user's eyes; and a housing that contains the display element and the light guide prism; and support unit that fixes the housing to user's head. The light guide prism is partially covered by and contained in the housing. A portion of side surface of the light guide prism covered by the housing is formed with a first groove, and portion of side surface of the light guide prism exposed outside the housing is formed with a second groove. Depth of the first groove measured from the side surface is greater than that of the second groove.

Head-mounted display device

The method for cleaning a reactor of the present invention comprises passing a solvent through a wax-fraction hydrocracking apparatus which is charged with a catalyst and to which supply of a wax fraction is stopped, wherein the solvent comprising at least one oil selected from a group consisting of hydrocarbon and vegetable oils, and having a sulfur content of less than 5 ppm and being in a liquid state at 15&#xb0; C.

Method for washing reactor

An inkjet printing apparatus includes an ink tank, a print head, an ink flow passage, a degassing device, a circulation flow passage and a circulation pump. The print head discharges ink supplied from the ink tank through the ink flow passage. The degassing device is disposed midway in the ink flow passage and removes air from the ink. The circulation flow passage has two ends respectively connected to two sides of the degassing device. The circulation pump is disposed midway in the circulation flow passage and returns the ink flowing out of the degassing device to a position to flow in the degassing device. The ink flow passage between an outflow port from the circulation flow passage and an inflow port thereto and the circulation flow passage are formed such that the ink is movable at approximately a constant speed.

Inkjet printing apparatus

A first light blocking portion and a second light blocking portion are formed in at least one of the side surfaces of a light guide prism. The first light blocking portion and the second light blocking portion are arranged so that a shaded area and an invisible area overlap each other at least partly and cover an inter-groove area between the first light blocking portion and the second light blocking portion, where the shaded area is an area shadowed from image light due to the first light blocking portion, and the invisible area is an area invisible during virtual image observation by the observer due to the second light blocking portion.

Virtual image observation optical system and light guide prism

A light guide prism for guiding image light from a display device to an observer's eye and displaying a virtual image of the display device in the observer's field of view includes at least four sides disposed to surround an optical path of image light incident from one end, a reflecting surface configured to reflect the image light guided by the at least four sides, and an emission surface configured to emit the image light reflected at the reflecting surface towards the observer's eye. At least one groove in a V-shape is formed on each of the at least four sides. As a result, a light guide prism that reduces stray light and ghost light occurring due to reflection at inner surfaces and an image display apparatus using this light guide prism can be provided.

Light guide prism and image display apparatus

Provided is a light guide prism including: an incident surface on which image light from a display device is incident; one or more reflection surfaces which reflect the image light incident thereon, the reflection surfaces including at least an emission side reflection surface; and an emission surface forming an acute angle with the emission side reflection surface and emitting the image light reflected by the emission side reflection surface, toward an eyeball of an observer. In one aspect, the light guide prism includes a prism tip disposed as protruding from an end of the emission side reflection surface and from an end of the emission surface, in a direction in which a width between the emission side reflection surface and the emission surface narrows. Further provided is an image display apparatus including: a display device which emits image light; the light guide prism; and a support.

Light-guiding prism and image display apparatus

Inkjet recording apparatus includes recording headhaving a plurality of nozzles N, first ink storage section, supply passageconnecting recording headand section, electromagnetic valvethat opens or closes section, second ink storage section, pump Pthat supplies the ink in sectionto section, an electromagnetic valvethat opens or closes the second storage ink section, recovery passagethat connects the recording headand the second storage section, and electromagnetic valvesandwhich open or close the recovery passage. Control unitallows ink inside the recording headto reflow to the second ink storage sectionby operating the pump Pin a state in which the electromagnetic valvesandare closed and the electromagnetic valveis opened.

Inkjet recording apparatus and recording head maintenance method

Provided is a light guide prism including: an incident surface; one or more reflection surfaces, the reflection surfaces including at least an emission side reflection surface; and an emission surface, in which the light guide prism has a tip face positioned between the emission side reflection surface and the emission surface, the tip face most protruding from an end of the emission side reflection surface and from an end of the emission surface in a direction in which a width between the emission side reflection surface and the emission surface narrows, the tip face being a curved face. Further provided is an image display apparatus including: a display device; the light guide prism; and a support.

Head mounted display prism

A noise reduction device comprises a SN ratio obtaining unit configured to obtain a SN ratio as a function of an estimated noise spectrum and an arithmetic product of an averaged power spectrum of the input signal and noise likeliness signal, and an output signal obtaining unit configured to obtain a output signal whose noise is reduced based on the input signal and the SN ratio obtained by the SN ratio obtaining unit.

Noise reduction device and noise reduction method

Growing community of inventors

Tokyo, Japan

Shinya Takahashi