Patents by Inventor Hiroaki Sakuta

Hiroaki Sakuta 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: 9070843
    Abstract: The present invention provides a semiconductor light-emitting device which emits light with high chroma, and an exhibit-irradiating illumination device, a meat-irradiating illumination device, a vegetable-irradiating illumination device, a fresh fish-irradiating illumination device, a general-purpose illumination device, and a semiconductor light-emitting system which include the semiconductor light-emitting device. A semiconductor light-emitting device 1 comprises an LED chip 10 as a semiconductor light-emitting element and a phosphor 20 which uses the LED chip 10 as an excitation source to emit light. The phosphor contains at least a green phosphor and a red phosphor, and a value of intensity of light with a wavelength of 660 nm in a spectrum of beam-normalized light emitted from the semiconductor light-emitting device 1 is 170% or more and 300% or less of a value of intensity of light with a wavelength of 660 nm in a spectrum of beam-normalized reference light for color rendering evaluation.
    Type: Grant
    Filed: June 14, 2013
    Date of Patent: June 30, 2015
    Assignee: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Hiroaki Sakuta, Yoshihito Satou
  • Publication number: 20140362885
    Abstract: The problem to be solved is to provide a semiconductor light emitting device attaining the improvement of the color rendering property in addition to the improvement of the light emission efficiency. The semiconductor light emitting device of the present invention including a cut filter configured to absorb light having a short wavelength equal to or less than 430 nm and transmit light having a long wavelength greater than 430 nm, wherein in a spectrum of the light emitted by the semiconductor light emitting device, light emission peak intensity deriving from the emitted light of the semiconductor light emitting element with respect to maximum intensity of the spectrum is equal to or lower than 50%. The above-mentioned problem is solved by using the semiconductor light emitting device.
    Type: Application
    Filed: August 25, 2014
    Publication date: December 11, 2014
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Hiroaki SAKUTA, Yuki Kohara
  • Patent number: 8890403
    Abstract: The present invention provides a technology that allows reducing the used amount of a Mn4+-activated fluoride complex phosphor without loss of luminous efficiency, in a white light-emitting device that is provided with the Mn4+-activated fluoride complex phosphor and an LED element that is an excitation source of the phosphor. The present invention provides a white light-emitting device comprises a blue LED element, as well as a yellow phosphor and/or a green phosphor and a red phosphor as phosphors that are excited by the blue LED element. The red phosphor contains a Mn4+-activated fluoride complex phosphor and a Eu2+-activated alkaline earth silicon nitride phosphor.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: November 18, 2014
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hiroaki Sakuta, Yoshihito Satou, Naoto Kijima, Byungchul Hong
  • Patent number: 8829778
    Abstract: A white light-emitting semiconductor device having improved reproducibility of bright red. The device outputs light having a blue component, a green component, and a red component. Each of the light components (blue, green, and red) is based on a light-emitting semiconductor element and/or a phosphor that absorbs light emitted by a light-emitting semiconductor element and emits light through wavelength conversion. The outputted light has a spectrum which has a maximum wavelength in the range of 615-645 nm, and the intensity at a wavelength of 580 nm of the outputted light, which has been normalized with respect to luminous flux, is 80-100% of the intensity at a wavelength of 580 nm of standard light for color rendering evaluation, which has been normalized with respect to luminous flux.
    Type: Grant
    Filed: September 30, 2013
    Date of Patent: September 9, 2014
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hiroaki Sakuta, Kazuhiko Kagawa, Yoshihito Satou, Hiroaki Okagawa, Shin Hiraoka
  • Patent number: 8829780
    Abstract: The invention aims at providing controllable parameters that are correlated with special color rendering index R9, and at providing a white-light emitting semiconductor device having a high R9 value obtained through optimization of such parameters. The white-light emitting semiconductor device is provided with a phosphor as a light-emitting material and with a light-emitting semiconductor element as an excitation source of the phosphor. The phosphor includes at least a green phosphor and a wide-band red phosphor. In the white light-emitting semiconductor device, an intensity at wavelength 640 nm of an emission spectrum which has been normalized with respect to luminous flux is 100-110% of the intensity at wavelength 640 nm of a spectrum of standard light for color rendering evaluation which has been normalized with respect to luminous flux.
    Type: Grant
    Filed: August 10, 2012
    Date of Patent: September 9, 2014
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hiroaki Sakuta, Kazuhiko Kagawa, Yoshihito Satou, Shin Hiraoka
  • Patent number: 8779455
    Abstract: The present invention provides a semiconductor light-emitting device that emits light with a specific low correlated color temperature and with a high Ra, and a semiconductor light-emitting system provided with the semiconductor light-emitting device. This object is attained by the semiconductor light-emitting device having the below-described configuration. A semiconductor light-emitting device includes a LED chip as a semiconductor light-emitting element, and a phosphor emitting light using the LED chip as an excitation source, and emits light with a correlated color temperature equal to or higher than 1600 K and lower than 2400 K. The phosphor includes at least a green phosphor and a red phosphor. In the spectrum of light emitted from the semiconductor light-emitting device, the value of the peak intensity of the light emitted by the LED chip is less than 60% of the maximum peak intensity of the light emitted by the phosphor.
    Type: Grant
    Filed: November 9, 2012
    Date of Patent: July 15, 2014
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hiroaki Sakuta, Yuki Kohara, Yoshihito Satou
  • Publication number: 20140042896
    Abstract: A white light-emitting semiconductor device having improved reproducibility of bright red. The device outputs light having a blue component, a green component, and a red component. Each of the light components (blue, green, and red) is based on a light-emitting semiconductor element and/or a phosphor that absorbs light emitted by a light-emitting semiconductor element and emits light through wavelength conversion. The outputted light has a spectrum which has a maximum wavelength in the range of 615-645 nm, and the intensity at a wavelength of 580 nm of the outputted light, which has been normalized with respect to luminous flux, is 80-100% of the intensity at a wavelength of 580 nm of standard light for color rendering evaluation, which has been normalized with respect to luminous flux.
    Type: Application
    Filed: September 30, 2013
    Publication date: February 13, 2014
    Applicant: Mitsubishi Chemical Corporation
    Inventors: Hiroaki SAKUTA, Kazuhiko Kagawa, Yoshihito Satou, Hiroaki Okagawa, Shin Hiraoka
  • Patent number: 8581488
    Abstract: A white light-emitting semiconductor device having improved reproducibility of bright red. The device outputs light having a blue component, a green component, and a red component. Each of the light components (blue, green, and red) consists of a light-emitting semiconductor element and/or a phosphor that absorbs light emitted by a light-emitting semiconductor element and emits light through wavelength conversion. The outputted light has a spectrum which has a maximum wavelength in the range of 615-645 nm, and the intensity at a wavelength of 580 nm of the outputted light, which has been normalized with respect to luminous flux, is 80-100% of the intensity at a wavelength of 580 nm of standard light for color rendering evaluation, which has been normalized with respect to luminous flux.
    Type: Grant
    Filed: November 9, 2011
    Date of Patent: November 12, 2013
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hiroaki Sakuta, Kazuhiko Kagawa, Yoshihito Satou, Hiroaki Okagawa, Shin Hiraoka
  • Publication number: 20130277694
    Abstract: The present invention provides a semiconductor light-emitting device which emits light with high chroma, and an exhibit-irradiating illumination device, a meat-irradiating illumination device, a vegetable-irradiating illumination device, a fresh fish-irradiating illumination device, a general-purpose illumination device, and a semiconductor light-emitting system which include the semiconductor light-emitting device. A semiconductor light-emitting device 1 comprises an LED chip 10 as a semiconductor light-emitting element and a phosphor 20 which uses the LED chip 10 as an excitation source to emit light. The phosphor contains at least a green phosphor and a red phosphor, and a value of intensity of light with a wavelength of 660 nm in a spectrum of beam-normalized light emitted from the semiconductor light-emitting device 1 is 170% or more and 300% or less of a value of intensity of light with a wavelength of 660 nm in a spectrum of beam-normalized reference light for color rendering evaluation.
    Type: Application
    Filed: June 14, 2013
    Publication date: October 24, 2013
    Inventors: Hiroaki SAKUTA, Yoshihito SATOU
  • Publication number: 20130264937
    Abstract: The present invention provides a technology that allows reducing the used amount of a Mn4+-activated fluoride complex phosphor without loss of luminous efficiency, in a white light-emitting device that is provided with the Mn4+-activated fluoride complex phosphor and an LED element that is an excitation source of the phosphor. The present invention provides a white light-emitting device comprises a blue LED element, as well as a yellow phosphor and/or a green phosphor and a red phosphor as phosphors that are excited by the blue LED element. The red phosphor contains a Mn4+-activated fluoride complex phosphor and a Eu2+-activated alkaline earth silicon nitride phosphor.
    Type: Application
    Filed: March 15, 2013
    Publication date: October 10, 2013
    Inventors: Hiroaki SAKUTA, Yoshihito SATOU, Naoto KIJIMA, Byungchul HONG
  • Patent number: 8508141
    Abstract: A light control apparatus for a LED light-emitting device comprises a driving current supply unit supplying an AC current as a driving current via a pair of terminals to the LED light-emitting device including a set of LED elements having mutually different light emission wavelength regions connected in parallel while providing opposite polarities and the pair of terminals provided to supply the driving current to the set of LED elements; an individual amount defining unit defining a positive driving current amount and a negative driving current amount respectively to be supplied to the LED light-emitting device in a positive half cycle and a negative half cycle included in one cycle of the AC current respectively.
    Type: Grant
    Filed: April 28, 2011
    Date of Patent: August 13, 2013
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Toru Takeda, Akeo Kasakura, Shinji Takai, Yoshihito Sato, Hiroaki Sakuta
  • Publication number: 20120319565
    Abstract: The invention aims at providing controllable parameters that are correlated with special color rendering index R9, and at providing a white light-emitting semiconductor device having a high R9 value obtained through optimization of such parameters. The white light-emitting semiconductor device is provided with a phosphor as a light-emitting material and with a light-emitting semiconductor element as an excitation source of the phosphor. The phosphor includes at least a green phosphor and a wide-band red phosphor. In the white light-emitting semiconductor device, an intensity at wavelength 640 nm of an emission spectrum which has been normalized with respect to luminous flux is 100-110% of the intensity at wavelength 640 nm of a spectrum of standard light for color rendering evaluation which has been normalized with respect to luminous flux.
    Type: Application
    Filed: August 10, 2012
    Publication date: December 20, 2012
    Applicant: Mitsubishi Chemical Corporation
    Inventors: Hiroaki SAKUTA, Kazuhiko Kagawa, Yoshihito Satou, Shin Hiraoka
  • Publication number: 20120286646
    Abstract: The present invention provides a blue (blue-green) phosphor that has sufficient emission intensity in the wavelength region around 490 nm and that has high emission luminance at a temperature region reached during LED operation. The present invention also provides a white light-emitting device that uses a high-luminance green phosphor having an emission peak wavelength of 535 nm or greater and that has improved bright blue reproducibility. A phosphor having a chemical composition of general formula [1] has sufficient emission intensity in a wavelength region around 490 nm, and a white light-emitting device that uses such a phosphor has improved bright blue reproducibility. (Sr, Ca)aBabEux(PO4)cXd??[1] (In general formula [1], X is Cl; c, d and x are numbers satisfying 2.7?c?3.3, 0.9?d?1.1 and 0.3?x?1.2; and a and b satisfy the conditions a+b=5?x and 0.12?b/(a+b)?0.4.
    Type: Application
    Filed: April 26, 2012
    Publication date: November 15, 2012
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Hiroaki SAKUTA, Kazuhiko Kagawa, Yoshihito Sato, Takatoshi Seto, Naoto Kijima
  • Publication number: 20120267999
    Abstract: The present invention provides a blue (blue-green) phosphor that has sufficient emission intensity in the wavelength region around 490 nm and that has high emission luminance at a temperature region reached during LED operation. The present invention also provides a white light-emitting device that uses a high-luminance green phosphor having an emission peak wavelength of 535 nm or greater and that has improved bright blue reproducibility. A phosphor having a chemical composition of general formula [1] has sufficient emission intensity in a wavelength region around 490 nm, and a white light-emitting device that uses such a phosphor has improved bright blue reproducibility. (Sr,Ca)aBabEux(PO4)cXd??[1] (In general formula [1], X is Cl; c, d and x are numbers satisfying 2.7?c?3.3, 0.9?d?1.1 and 0.3?x?1.2; and a and b satisfy the conditions a+b=5?x and 0.12?b/(a+b)?0.4.).
    Type: Application
    Filed: March 2, 2012
    Publication date: October 25, 2012
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Hiroaki Sakuta, Kazuhiko Kagawa, Yoshihito Sato, Takatoshi Seto, Naoto Kijima
  • Publication number: 20120212123
    Abstract: The present invention provides a blue (blue-green) phosphor that has sufficient emission intensity in the wavelength region around 490 nm and that has high emission luminance at a temperature region reached during LED operation. The present invention also provides a white light-emitting device that uses a high-luminance green phosphor having an emission peak wavelength of 535 nm or greater and that has improved bright blue reproducibility. A phosphor having a chemical composition of general formula [1] has sufficient emission intensity in a wavelength region around 490 nm, and a white light-emitting device that uses such a phosphor has improved bright blue reproducibility. (Sr,Ca)aBabEux(PO4)cXd??[1] (In general formula [1], X is Cl; c, d and x are numbers satisfying 2.7?c?3.3, 0.9?d?1.1 and 0.3?x?1.2; and a and b satisfy the conditions a+b=5?x and 0.05?b/(a+b)?0.6.
    Type: Application
    Filed: February 29, 2012
    Publication date: August 23, 2012
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Hiroaki SAKUTA, Kazuhiko Kagawa, Yoshihito Sato, Takatoshi Seto, Naoto Kijima
  • Publication number: 20120112626
    Abstract: A white light-emitting semiconductor device having improved reproducibility of bright red. The device outputs light having a blue component, a green component, and a red component. Each of the light components (blue, green, and red) consists of a light-emitting semiconductor element and/or a phosphor that absorbs light emitted by a light-emitting semiconductor element and emits light through wavelength conversion. The outputted light has a spectrum which has a maximum wavelength in the range of 615-645 nm, and the intensity at a wavelength of 580 nm of the outputted light, which has been normalized with respect to luminous flux, is 80-100% of the intensity at a wavelength of 580 nm of standard light for color rendering evaluation, which has been normalized with respect to luminous flux.
    Type: Application
    Filed: November 9, 2011
    Publication date: May 10, 2012
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Hiroaki SAKUTA, Kazuhiko KAGAWA, Yoshihito Satou, Hiroaki Okagawa, Shin Hiraoka
  • Publication number: 20110260633
    Abstract: A light control apparatus for a LED light-emitting device comprises a driving current supply unit supplying an AC current as a driving current via a pair of terminals to the LED light-emitting device including a set of LED elements having mutually different light emission wavelength regions connected in parallel while providing opposite polarities and the pair of terminals provided to supply the driving current to the set of LED elements; an individual amount defining unit defining a positive driving current amount and a negative driving current amount respectively to be supplied to the LED light-emitting device in a positive half cycle and a negative half cycle included in one cycle of the AC current respectively.
    Type: Application
    Filed: April 28, 2011
    Publication date: October 27, 2011
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Toru Takeda, Akeo Kasakura, Shinji Takai, Yoshihito Sato, Hiroaki Sakuta