Patents by Inventor Toshitaka Nakajima

Toshitaka Nakajima 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: 20190366949
    Abstract: A license plate sheet having superior weather resistance is provided. A license plate comprising the license plate sheet and having markings visible to a infrared-based ALPR system, is also provided. In some embodiments, the license plate sheet includes an infrared absorbing marking layer, wherein the infrared absorbing marking layer includes cesium tungsten oxide and a binder.
    Type: Application
    Filed: July 25, 2019
    Publication date: December 5, 2019
    Inventors: Akira Muramoto, Toshitaka Nakajima
  • Patent number: 10406998
    Abstract: A license plate sheet having superior weather resistance is provided. A license plate comprising the license plate sheet and having markings visible to a infrared-based ALPR system, is also provided. In some embodiments, the license plate sheet includes an infrared absorbing marking layer, wherein the infrared absorbing marking layer includes cesium tungsten oxide and a binder.
    Type: Grant
    Filed: June 19, 2013
    Date of Patent: September 10, 2019
    Assignee: 3M Innovative Properties Company
    Inventors: Akira Muramoto, Toshitaka Nakajima
  • Patent number: 10365418
    Abstract: The disclosed retroreflective sheet contains a retroreflective layer and a polyurethane surface protecting layer, wherein the surface protecting layer contains at least a reaction product of a polyol with either a polyester backbone or a polycarbonate backbone and a trifunctional or higher aliphatic isocyanate, and the glass transition temperature Tg of the surface protecting layer is 50° C. or higher, and the tan ? of the loss tangent at 120° C. is 0.1 or less.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: July 30, 2019
    Assignee: 3M INNOVATIVE PROPERTIES COMPANY
    Inventors: Saori Ueda, Toshitaka Nakajima, Yorinobu Takamatsu, Ken Egashira, Koji Saito
  • Publication number: 20170357039
    Abstract: The disclosed retroreflective sheet contains a retroreflective layer and a polyurethane surface protecting layer, wherein the surface protecting layer contains at least a reaction product of a polyol with either a polyester backbone or a polycarbonate backbone and a trifunctional or higher aliphatic isocyanate, and the glass transition temperature Tg of the surface protecting layer is 50° C. or higher, and the tan ? of the loss tangent at 120° C. is 0.1 or less.
    Type: Application
    Filed: December 17, 2015
    Publication date: December 14, 2017
    Inventors: Saori Ueda, Toshitaka Nakajima, Yorinobu Takamatsu, Ken Egashira, Koji Saito
  • Patent number: 9519087
    Abstract: The present application relates to retroreflective sheeting that is capable of use in a license plate and that can be accurately read and/or detected by an ALPR system. The retroreflective sheeting is a prismatic retroreflective sheeting that provides reduced retroreflectivity of infra-red light. The retroreflective sheeting can also be a prismatic retroreflective sheeting that exhibits reduced retroreflectivity of incident infra-red light and substantially unaffected retroreflectivity of incident visible light.
    Type: Grant
    Filed: October 12, 2010
    Date of Patent: December 13, 2016
    Assignee: 3M Innovative Properties Company
    Inventors: Toshitaka Nakajima, Masami Yokoyama, Akira Muramoto
  • Patent number: 9110235
    Abstract: The present application relates to retroreflective sheeting that is capable of use in a license plate and that can be accurately read and/or detected by an ALPR system. The retroreflective sheeting is a microsphere-based retroreflective sheeting that provides reduced retroreflectivity at high entrance angles. The retroreflective sheeting can also be a microsphere-based retroreflective sheeting that exhibits reduced retroreflectivity of incident infra-red light from high entrance angles and substantially unaffected retroreflectivity of incident visible light from entrance angles in the vicinity of the normal.
    Type: Grant
    Filed: October 12, 2010
    Date of Patent: August 18, 2015
    Assignee: 3M Innovative Properties Company
    Inventors: Toshitaka Nakajima, Masami Yokoyama, Akira Muramoto, Bruce D. Orensteen
  • Publication number: 20150191132
    Abstract: A license plate sheet having superior weather resistance is provided. A license plate comprising the license plate sheet and having markings visible to a infrared-based ALPR system, is also provided. In some embodiments, the license plate sheet includes an infrared absorbing marking layer, wherein the infrared absorbing marking layer includes cesium tungsten oxide and a binder.
    Type: Application
    Filed: June 19, 2013
    Publication date: July 9, 2015
    Inventors: Akira Muramoto, Toshitaka Nakajima
  • Patent number: 8496339
    Abstract: A transparent wavelength-selective retroreflector (100) that retroreflects light within a specific wavelength range and is transparent to visible light. A transparent wavelength-selective retroreflector allows visible light to pass therethrough and selectively retroreflects light within a specific wavelength range. One preferred embodiment of a transparent, wavelength-selective retroreflector includes an optical structure layer (101) that is made of a light transmissible material and a wavelength selective reflective layer (102). At least one of the front or rear surfaces includes a cube corner structure, such as cube-corner type trigonal pyramids, cube-corner type cavities, cube-corner type trigonal pyramids with reflective layers, cube-corner type cavities with reflective layers, and the like.
    Type: Grant
    Filed: June 26, 2006
    Date of Patent: July 30, 2013
    Assignee: 3M Innovative Properties Company
    Inventor: Toshitaka Nakajima
  • Publication number: 20120200709
    Abstract: The present application relates to retroreflective sheeting that is capable of use in a license plate and that can be accurately read and/or detected by an ALPR system. The retroreflective sheeting is a microsphere-based retroreflective sheeting that provides reduced retroreflectivity at high entrance angles. The retroreflective sheeting can also be a microsphere-based retroreflective sheeting that exhibits reduced retroreflectivity of incident infra-red light from high entrance angles and substantially unaffected retroreflectivity of incident visible light from entrance angles in the vicinity of the normal.
    Type: Application
    Filed: October 12, 2010
    Publication date: August 9, 2012
    Inventors: Toshitaka Nakajima, Masami Yokoyama, Akira Muramoto, Bruce D. Orensteen
  • Publication number: 20120200710
    Abstract: The present application relates to retroreflective sheeting that is capable of use in a license plate and that can be accurately read and/or detected by an ALPR system. The retroreflective sheeting is a prismatic retroreflective sheeting that provides reduced retroreflectivity of infra-red light. The retroreflective sheeting can also be a prismatic retroreflective sheeting that exhibits reduced retroreflectivity of incident infra-red light and substantially unaffected retroreflectivity of incident visible light.
    Type: Application
    Filed: October 12, 2010
    Publication date: August 9, 2012
    Inventors: Toshitaka Nakajima, Masami Yokoyama, Akira Muramoto
  • Publication number: 20100277801
    Abstract: A transparent wavelength-selective retroreflector (100) that retroreflects light within a specific wavelength range and is transparent to visible light. A transparent wavelength-selective retroreflector allows visible light to pass therethrough and selectively retroreflects light within a specific wavelength range. One preferred embodiment of a transparent, wavelength-selective retroreflector includes an optical structure layer (101) that is made of a light transmissible material and a wavelength selective reflective layer (102). At least one of the front or rear surfaces includes a cube corner structure, such as cube-corner type trigonal pyramids, cube-corner type cavities, cube-corner type trigonal pyramids with reflective layers, cube-corner type cavities with reflective layers, and the like.
    Type: Application
    Filed: June 26, 2006
    Publication date: November 4, 2010
    Inventor: Toshitaka Nakajima
  • Patent number: 6120879
    Abstract: A reflective article has a structured surface which includes a first and second array of reflective elements. The first array includes elements which have at least a first, second, and third reflecting face arranged to retroreflect incident light in a retroreflected beam. The second array includes elements which have at least a fourth, fifth, and sixth reflecting face arranged to reflect incident light in a second beam at an observation angle greater than 2 degrees. In signing applications, the second beam can be light originating from a stationary light source, the second beam having a direction and beam width suitable for illuminating an observation zone of interest. The retroreflected beam can be light originating from a moving light source such as a vehicle headlamp. Sheeting comprising such an article can be used both where external lighting from a suitable stationary light source is available and where it is not available.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: September 19, 2000
    Assignee: 3M Innovative Properties Company
    Inventors: Theodore J. Szczech, Toshitaka Nakajima, Mark D. Fiegen
  • Patent number: 6048069
    Abstract: An imaging element is disposed on a front surface of a retroreflective sheeting to form an image-displaying sheeting. The imaging element includes a light-transmitting prismatic sheeting that has a surface provided with a plurality of parallel prisms. The imaging element also includes an adhesive layer that adheres the prismatic sheeting to the front surface of the retroreflective sheeting. At least a portion of the imaging element is shaped in the form of indicia. In some cases the prismatic sheeting itself is shaped in the form of indicia. In other cases the imaging element includes a light-transmitting colored layer disposed on the front surface of the retroreflective sheeting and shaped in the form of indicia. In the latter case, the prismatic sheeting can be shaped as before to match the indicia-shaped colored layer, or it can extend continuously across the entire retroreflective sheeting.
    Type: Grant
    Filed: March 9, 1999
    Date of Patent: April 11, 2000
    Assignee: 3M Innovative Properties Company
    Inventors: Yoshiyuki Nagaoka, Toshitaka Nakajima
  • Patent number: 5818640
    Abstract: This relates to a system for and method of illuminating a sign, so that drivers and observers may easily recognize and read the sign and billboard. The apparatus employs an external illumination source that is easy to inspect and maintain. The illumination source and the sign or billboard are separately installed from each other. Light emitted from the illumination source forms an incident angle (.theta.) in the range of 0.degree. to about 30.degree. at any point on the road sign. A road sign area of the sign is made of a retroreflective sheet having a wide observation angle.
    Type: Grant
    Filed: January 30, 1997
    Date of Patent: October 6, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Yoshio Watanabe, Toshitaka Nakajima, Muneo Momozawa, Satoshi Kakishita
  • Patent number: 5777790
    Abstract: A retroreflective article comprising a monolayer of microspheres partially embedded in and protruding from a binder layer and specular reflector underlying the microspheres, wherein the monolayer of microspheres comprises a mixture of a first class of microspheres having a first refractive index and a second class of microspheres having a second refractive index wherein the second refractive index is higher than the first refractive index. As a result, the sheeting exhibits superior observation angle angularity.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: July 7, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Toshitaka Nakajima
  • Patent number: 4652536
    Abstract: Tellurite glass is disclosed, consisting essentially of 60 to 85 mol % of TeO.sub.2, up to 25 mol % of Li.sub.2 O, up to 35 mol % of Na.sub.2 O, up to 25 mol % of K.sub.2 O, up to 25 mol % of Rb.sub.2 O, up to 15 mol % of Cs.sub.2 O, up to 10 mol % of MgO, up to 5 mol % of CaO, up to 5 mol % of SrO, 1 to 30 mol % of BaO, up to 30 mol % of ZnO, up to 30 mol % of PbO, and up to 5 mol % in total of La.sub.2 O.sub.3, ZrO.sub.2, TiO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5 and WO.sub.3 with the total content of K.sub.2 O, Rb.sub.2 O and Cs.sub.2 O being from 1 to 25 mol %, and the total content of ZnO and PbO being from 1 to 30 mol %. The tellurite glass has a reduced light path difference with temperature difference and an increased figure of merit.
    Type: Grant
    Filed: June 30, 1986
    Date of Patent: March 24, 1987
    Assignee: Hoya Corporation
    Inventors: Toshitaka Nakajima, Hiroji Sagara
  • Patent number: 3938014
    Abstract: A brushless d-c motor of the type having a permanent magnet rotor and a plurality of stator windings which are energized from a common d-c power source through transistors in response to means which detect the rotating position of the rotor in a manner such that the conductance of the transistors are so controlled as to ensure proper rotation, in which, means are provided for detecting the currents flowing through the stator windings and the outputs of these means used to control the transistors supplying current to the stators such as to equalize the current flow from stator winding to stator winding, thereby permitting transistors having unmatched gains to be used in the motor.
    Type: Grant
    Filed: February 14, 1974
    Date of Patent: February 10, 1976
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Toshitaka Nakajima