Patents by Inventor Tadashi Koyama
Tadashi Koyama 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).
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Patent number: 6291797Abstract: In a laser processing method for accurately forming a convexo-concave structure on the surface of a glass substrate, a periodic optical intensity distribution of a laser beam is obtained by an interference between diffracted light beams of +1 degree and −1 degree emitted from a phase mask, onto which the laser beam is irradiated, in the vicinity of the emission side of the phase mask, and a glass substrate, on which a thin film is formed, is set in the area where the periodic optical intensity distribution is provided. As a result, the thin film is evaporated or ablated depending on the periodic optical intensity, thereby a diffraction grating, which has the same period as that of the varying optical intensity, is formed on the glass substrate.Type: GrantFiled: June 4, 1999Date of Patent: September 18, 2001Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Tadashi Koyama, Keiji Tsunetomo
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Patent number: 6285037Abstract: In a method for detecting liquid drops adhering upon a front windshield with superior sensitivity but without obstructing drivers, a light beam emitted from a light emitting element 4 is guided into a light guiding body 7, and after undergoing total internal reflection within light guiding body 7, it is guided into a front windshield G. The light guided into the front windshield G is received by a light receiving element 5 after repeated total internal reflections within the front windshield G. In this instance, when raindrops adhere on the outside surface of the front windshield G and the adhering points are at the total internal reflection points of the light mentioned above, then the light beam guided into the front windshield G passes through and goes out from the windshield G without undergoing total internal reflection therein.Type: GrantFiled: August 20, 1999Date of Patent: September 4, 2001Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Tadashi Koyama, Shuhei Tanaka, Keiji Tsunetomo
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Publication number: 20010012865Abstract: The invention relates to a flame-retardant thermoplastic resin composition having incorporated therein a trace of stabilized red phosphorus, which achieves both improvement of heat resistance and flame retardation without using chlorine nor bromine and also possesses long-term heat stability and smells little. The composition comprises (A) 50 to 95 parts by weight of a polycarbonate resin and (B) 5 to 50 parts by weight of a thermoplastic polyester resin, contains (C) 0.1 to 5 parts by weight, per 100 parts by weight of the total amount of (A) and (B), of coated stabilized red phosphorus and preferably contains (D) 0.1 to 100 parts by weight, per 100 parts by weight of the total amount of (A) and (B), of a silicate compound.Type: ApplicationFiled: October 6, 1998Publication date: August 9, 2001Applicant: KANEKA CORPORATIONInventors: KAZUAKI MATSUMOTO, TADASHI KOYAMA, YOSHITAKA ONO, KATSUTOYO FUJITA, YOICHI OHARA, KAZUSHI HIROBE
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Patent number: 6262389Abstract: A sheet of silicate glass having a thickness of 2 mm and composed mainly of SiO2, and containing Al2O3, B2O3, Na2O, F, etc., is immersed in a molten salt comprising a mixture of 50 mol % of silver nitrate and 50 mol % of sodium nitrate. Na ions in the surface of the glass are eluted, diffusing Ag ions in the molten salt into the glass. When a laser beam is applied to the glass substrate thus formed, the glass substrate is evaporated or ablated progressively from its surface. The glass substrate is processed to a smooth finish without causing cracking or breakage.Type: GrantFiled: September 22, 1998Date of Patent: July 17, 2001Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Tadashi Koyama, Keiji Tsunetomo
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Patent number: 6239444Abstract: A water drop detection device for detecting an amount of water drops present upon a surface of a transparent substrate in which a light source with a driver circuit guides light into the substrate so as to cause the light to under go internal reflection within the substrate. The light source has a light emitting element and a receiving light sensing element for detecting the light output from the emitting element. The light output from the light emitting element is modulated by a predetermined frequency. A signal corresponding to the modulated component is separated from the output signal of the receiving light sensing element. The output light emission of the light emitting element is maintained at a desired value by feeding the separated signal back to the driver circuit of the light emitting element.Type: GrantFiled: May 5, 2000Date of Patent: May 29, 2001Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Shuhei Tanaka, Tadashi Koyama, Keiji Tsunetomo
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Patent number: 6239570Abstract: A wiper controller apparatus of the water drop sensitive type comprises: light emitting means 7 for guiding light into a window glass so as to undergo total internal reflection within said window glass; light receiving means 8 for receiving the light which has undergone total internal reflection within said window glass; means for detecting the amount of water drops adhered or present upon an outside surface of said window glass based on an output of said light receiving means, and for driving a wiper thereupon; wherein the apparatus further comprises wiper driving means 18 for driving the wiper again by only one cycle if a time interval from an initiation of said wiper action exceeds a predetermined time. The apparatus further comprises anther wiper driving means 18 for driving said wiper when the signal duration time of the output signal S1 of said light receiving means 8 is equal to or greater than a predetermined time.Type: GrantFiled: December 16, 1998Date of Patent: May 29, 2001Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Shuhei Tanaka, Tadashi Koyama, Keiji Tsunetomo
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Patent number: 6220058Abstract: A laser processing method for removing glass by melting, evaporation or ablation from sheet-like glass substrate for forming microscopic concavities and convexities. Diffraction grating and planar microlens array obtained thereby.Type: GrantFiled: September 22, 1998Date of Patent: April 24, 2001Assignee: Nippon Sheet Glass Co., LTDInventors: Tadashi Koyama, Keiji Tsunetomo, Masahiro Oikawa, Kenjiro Hamanaka
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Patent number: 6174943Abstract: A flame retarded thermoplastic resin composition comprising (R) a thermoplastic resin comprising (A) a polycarbonate resin and (B) an aromatic polyester resin in an (A)/(B) ratio of 99/1 to 50/50 by weight, and per 100 parts by weight of the thermoplastic resin (R), (C) 0.5 to 100 parts by weight of a silicate compound and (D) 0.5 to 30 parts by weight of an organic phosphorus based flame retarder. The composition can exhibit excellent flame resistance and anti-drip property without containing a halogen atom and, moreover, has excellent properties such as heat resistance, mechanical strength, solvent resistance, surface property of moldings, and dimensional stability.Type: GrantFiled: April 2, 1998Date of Patent: January 16, 2001Assignee: Kaneka CorporationInventors: Kazuaki Matsumoto, Tadashi Koyama, Yoshitaka Ono, Katsutoyo Fujita, Yoichi Ohara, Kazushi Hirobe
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Patent number: 6147753Abstract: A liquid drop detector which may be fixed or attached by a simple operation, without machining, to a window glass, includes a light emitting element, a light receiving element and light guiding bodies wherein the light emitted by the light emitting element is introduced through a diffraction grating into a first light guiding body and after undergoing total internal reflection within the first light guiding body it is introduced through a silicon member, through an elongated light guiding body, through an additional silicon member, and into a windshield. After traveling within the windshield by total internal reflection, the light passes through a silicon member, reenters the elongated light guiding body, passes through another silicon member and enters a second light guiding body which guides it to a receiver.Type: GrantFiled: May 10, 1999Date of Patent: November 14, 2000Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Tadashi Koyama, Keiji Tsunetomo, Shuhei Tanaka, Hideki Imanishi
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Patent number: 6143382Abstract: A glass substrate having fine holes formed therein by use of a laser beam without cracks or fragmentation occurring. A glass substrate is used in which silver is contained in the form Ag atoms, Ag colloid or Ag ions, to a predetermined depth from a surface of the glass, and further the concentration gradient of the silver is a maximum at one side surface on which the fine hole machining is performed and gradually decreases toward the other side surface, whereby ablation and evaporation occurs from the surface having the maximum concentration of silver layer by layer without causing cracking or fragmentation.Type: GrantFiled: June 2, 1998Date of Patent: November 7, 2000Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Tadashi Koyama, Keiji Tsunetomo, Hideki Imanishi
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Patent number: 6097167Abstract: A water drop detection device for detecting an amount of water drops present upon a surface of a transparent substrate in which a light source with a driver circuit guides light into the substrate so as to cause the light to under go internal reflection within the substrate. The light source has a light emitting element and a receiving light sensing element for detecting the light output from the emitting element. The light outputted from the light emitting element is modulated by a predetermined frequency. A signal corresponding to the modulated component is separated from the output signal of the receiving light sensing element. The output light emission of the light emitting element is controlled as a desired value by feeding the separated signal back to the driver circuit of the light emitting element.Type: GrantFiled: July 22, 1998Date of Patent: August 1, 2000Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Shuhei Tanaka, Tadashi Koyama, Keiji Tsunetomo
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Patent number: 6019606Abstract: A robot teaching machine according to the present invention includes a guiding tool having a first angle sensor, a coordinate detector having a plurality of rotating portions and a second angle sensor for detecting a rotational angle of each of the rotating portions, a first motion transfer member for detecting a distance between the guiding tool and the coordinate detector that are connected with each other, a second motion transfer member for connecting the guiding tool and the coordinate detector and detecting an attitude of the guiding tool, and a coordinate converter for deriving a three-dimensional position and an attitude of the guiding tool from values detected by the first and the second angle sensors, respectively. The first motion transfer member and the second motion transfer member independently work for providing precise guiding data.Type: GrantFiled: November 10, 1997Date of Patent: February 1, 2000Assignee: Toyoda Koki Kabushiki KaishaInventors: Katsumi Yamamoto, Tadashi Koyama, Shinichi Sugita, Toshiro Itaya
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Patent number: 6008467Abstract: In a method for forming a hole for fitting an optical fiber only at a core portion without having to precisely match or accord the focus of a laser beam with the end surface of an optical waveguide, when a laser beam is irradiated onto the end surface of the optical waveguide, the focus of the laser beam is turned away from the end surface of the optical waveguide and a region of the irradiation includes the core and the periphery thereof. Thereafter, the energy of the laser beam is increased step by step, and a few pulses thereof are radiated with the intensity fixed when ablation occurs at the core portion, so that the hole is formed only at the core portion.Type: GrantFiled: October 3, 1997Date of Patent: December 28, 1999Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Keiji Tsunetomo, Tadashi Koyama
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Patent number: 5998782Abstract: A windshield (transparent substrate) 1 having the function of detecting the presence of water drops W upon one side surface of the windshield depending upon variations in an amount of reflected light, comprising a rain sensor provided on the other side surface of the windshield, which further comprises: light emitting means 6 for guiding light into the windshield 1; light receiving means 7 for detecting the light which is reflected within the windshield 1; and, light shielding members 10 and 11 provided on the other side surface of the windshield 1 opposing the light emitting means 6 and the light receiving means 7, respectively; wherein the light shielding member 10 shields the light emitted from the light emitting means 6 at an incident angle less than a critical angle at which total internal reflection occurs at a boundary surface between air and the windshield 1, while the other shielding member 11 shields outside ambient light incident upon the light receiving means 7.Type: GrantFiled: November 13, 1998Date of Patent: December 7, 1999Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Tadashi Koyama, Keiji Tsunetomo, Shuhei Tanaka, Hideki Imanishi
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Patent number: 5991049Abstract: A front windshield 1 having a rain sensor 2 for detecting the adhesion or presence of water drops W upon one side surface thereof, depending upon variation in an amount of reflected light, wherein the rain sensor 2 comprises: a light emitting element 7 for introducing a sensing light beam into the front windshield 1; a light receiving element 8 for detecting the light beam which is propagated by total internal reflection within the front windshield 1; and diffraction gratings 5, 6 formed on a surface of a glass substrate 4, through which the light emitting element 7 and the light receiving element 8 are provided on glass surface, whereby the rain sensor 2 is adhered on the other side surface of the front windshield 1 by means of an adhesive material 3 having a refractive index equivalent to that of the glass substrate 4.Type: GrantFiled: July 22, 1998Date of Patent: November 23, 1999Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Shuhei Tanaka, Tadashi Koyama, Keiji Tsunetomo, Hideki Imanishi
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Patent number: 5951731Abstract: For forming bores for insertion of optical fibers, etc., on one side surface of a micro lens with high accuracy and easy work, a laser processing method that includes the steps of: irradiating a laser beam onto the one side surface of the micro lens; then focusing the laser beam in a layer having superiority in absorbency with respect to the laser beam; and forming the bores because the laser beam exceeds the threshold value of causing fusion, evaporation or ablation in the superior laser beam absorption layer.Type: GrantFiled: October 3, 1997Date of Patent: September 14, 1999Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Keiji Tsunetomo, Tadashi Koyama
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Patent number: 5917603Abstract: A wiper control apparatus of the water drop sensitive type for detecting of the amount of water or water drops adhering to or present upon the front surface of a windshield and for driving a wiper, comprising: a light emitting means for introducing light into the inside of the windshield so that the light experiences total internal reflection upon interior surfaces of the windshield; a light receiving means for receiving the light reflected within the windshield; means for turning a first output D1, a second output D2, and a third output D3 to either an H level or an L level in response to the level of a signal output from the light receiving means, the outputs being preset in sequence of height of sensitivity thereof; means for outputting a drive signal WD for the wiper when outputs D1, D2, and D3 are switched into the H level; means for maintaining the drive signal as long as the second output signal D2 is in the H level even if the third output D3 turns to the L level; and means for stopping the drive signType: GrantFiled: July 22, 1998Date of Patent: June 29, 1999Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Shuhei Tanaka, Tadashi Koyama, Keiji Tsunetomo
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Patent number: 5910256Abstract: In a method for manufacturing a diffraction type optical element having an arbitrary cross-section, a laser beam of a single mode is divided into two and then is again focused on a thin film on a substrate, thereby obtaining a laser beam pattern changing periodically in intensity through interference thereof which is then irradiated onto the substrate while the substrate is positioned inclined with respect to a plane which is perpendicular to an average light beam axis of the two laser beams.Type: GrantFiled: August 13, 1997Date of Patent: June 8, 1999Assignee: Nippon Sheet Glass Co., Ltd.Inventors: Keiji Tsunetomo, Tadashi Koyama
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Patent number: 5886088Abstract: There are provided a polyethylene terephthalate resin composition in which to 100 parts by weight of a polyethylene terephthalate resin (A) polymerized by use of a germanium catalyst and having at least 80% of an ethylene terephthalate repetition unit, 0.05 to 30 parts by weight of a compound selected from the group consisting of an epoxy compound having at least two intramolecular epoxy groups without any intramolecular ester linkage and a carbodiimide compound (B) is formulated, and resin compositions in which a fibrous reinforcing material (C), a block copolymer (D) and an inorganic nucleating agent (E) are further formulated in the above mentioned composition. The resin composition of the present invention is excellent in moist heat resistance, fluidity and mechanical strength, and in addition, can be subjected to high cycle molding even in a mold of a low temperature to yield a molded article with improved surface characteristics.Type: GrantFiled: October 21, 1996Date of Patent: March 23, 1999Assignee: Kanegafuchi Kagaku Kogyo Kabushiki KaishaInventors: Kazuaki Matsumoto, Masahiko Mihoichi, Youichi Ohara, Kazushi Hirobe, Kenji Mogami, Tadashi Koyama
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Patent number: 5871570Abstract: There is dsiclosed a flame retardant resin composition comprising the following components (A), (B), (C), (D), (E) and (F), wherein 1-10 parts by weight of (C), 2-10 parts by weight of (D), 0.05-2 parts by weight of (E) and 0.01-10 parts by weight of (F) are contained per 100 parts by weight of a resin whose weight ratio of (A)/(B) is 75/25-90/10.(A) a polycarbonate resin whose viscosity-average molecular weight is 16,000-29,000,(B) a polyalkylene terephthalate resin,(C) a copolymer containing a rubbery polymer and at least one selected from the group consisting of aromatic vinyl monomers, vinyl cyanide monomers, acrylic acid, acrylic esters, methacrylic acid, methacrylic esters and maleimide-type monomers as components,(D) an organic phosphorus-type flame retardant,(E) a fluorocarbon-type resin, and(F) an epoxy compound not containing halogens.Type: GrantFiled: November 24, 1997Date of Patent: February 16, 1999Assignee: Kanegafuchi Kagaku Kogyo Kabushiki KaishaInventors: Tadashi Koyama, Kenji Mogami, Masahiro Asada