Patents by Inventor Taku Kumasaka
Taku Kumasaka 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: 10170674Abstract: Provided is an LED device presenting minimal risk of bottom-surface contamination even when foreign substances such as liquids adhere thereto. The LED device has an LED die, a submount substrate on the surface of which the LED die is mounted, a frame-shaped electrode disposed along the outer circumferential part of the bottom surface of the submount substrate, and an inner-side electrode surrounded by the frame-shaped electrode and connected to the electrode of the LED die. In the LED device, the frame-shaped electrode is disposed along the entire outer circumferential part of the bottom surface. In an LED device, the bottom surface is rectangular, and the frame-shaped electrode is disposed along three sides of the bottom surface.Type: GrantFiled: June 23, 2014Date of Patent: January 1, 2019Assignees: Citizen Watch Co., Ltd., Citizen Electronics Co., Ltd.Inventors: Isao Miyashita, Taku Kumasaka, Keita Watanabe, Kosuke Tsuchiya
-
Publication number: 20160197253Abstract: Provided is an LED device presenting minimal risk of bottom-surface contamination even when foreign substances such as liquids adhere thereto. The LED device has an LED die, a submount substrate on the surface of which the LED die is mounted, a frame-shaped electrode disposed along the outer circumferential part of the bottom surface of the submount substrate, and an inner-side electrode surrounded by the frame-shaped electrode and connected to the electrode of the LED die. In the LED device, the frame-shaped electrode is disposed along the entire outer circumferential part of the bottom surface. In an LED device, the bottom surface is rectangular, and the frame-shaped electrode is disposed along three sides of the bottom surface.Type: ApplicationFiled: June 23, 2014Publication date: July 7, 2016Applicants: CITIZEN HOLDINGS CO., LTD., CITIZEN ELECTRONICS CO., LTD.Inventors: Isao Miyashita, Taku Kumasaka, Keita Watanabe, Kosuke Tsuchiya
-
Patent number: 8390760Abstract: A planar light-emitting device enabling reduction in the deflection of a sheet-shaped light-diffusing element includes a reflector having an upper surface serving as a light-reflecting surface, a partition provided on the reflector to extend upward to form a plurality of enclosed spaces over the upper surface of the reflector, light sources disposed in the enclosed spaces, respectively, and at least one sheet-shaped light-diffusing element supported on the upper edges of the partition to transmit and diffuse light from the light sources upward. The side surfaces of the partition that define the enclosed spaces are light-reflecting surfaces.Type: GrantFiled: December 3, 2009Date of Patent: March 5, 2013Assignees: Citizen Electronics Co., Ltd., Citizen Holdings Co., Ltd.Inventors: Takeshi Ogihara, Daisaku Okuwaki, Makoto Yasuhara, Taku Kumasaka
-
Patent number: 8368838Abstract: A planar light-emitting device enabling more precise local dimming has a plurality of light-emitting units each including a lightguide plate and a plurality of light sources disposed successively in the lateral width direction of the light-entrance surface and adjacently facing a light-entrance surface of the lightguide plate to emit light into the lightguide plate through the light-entrance surface. The light sources are divided into a plurality of groups successively arranged in the width direction, each group including at least one light source. The lightguide plates of the light-emitting units are mutually adjacently disposed with their light-exiting surfaces being flush with each other. The planar light-emitting device has a light source output control unit that controls the outputs of the light sources for each group.Type: GrantFiled: July 8, 2009Date of Patent: February 5, 2013Assignee: Citizen Electronics Co., Ltd.Inventors: Taku Kumasaka, Daisaku Okuwaki
-
Patent number: 8279372Abstract: A planar light-emitting device comprises a plurality of light-emitting units each including a lightguide plate and arranged adjacent to each other. Each lightguide plate has an upper surface as a light-exiting surface, a lower surface opposite to the upper surface, and a peripheral side surface extending between the peripheral edges of the upper surface and the lower surface, wherein a light-entrance surface is defined by a part of the peripheral side surface. The light-entrance surface has a first protruding portion extending from and along the light-entrance surface and an opposite surface opposing the light-entrance surface has a second protruding portions extending from and along the opposite surface. In each adjacently disposed pair of light-emitting units, the first protruding portion of the first light-emitting unit abuts against the second protruding portion of the second light-emitting unit. The light source is disposed underneath the abutting first and second protruding portions.Type: GrantFiled: May 4, 2009Date of Patent: October 2, 2012Assignee: Citizen Electronics Co., Ltd.Inventors: Takashi Shimura, Taku Kumasaka
-
Patent number: 8194206Abstract: A planar light-emitting device allowing for high luminance uniformity has a plurality of light-emitting units (4), each including a lightguide plate (3) having a light-exiting surface, an opposite surface opposite to the light-exiting surface, a peripheral side surface extending between the respective peripheral edges of the light-exiting surface and the opposite surface, and a light-entrance surface (3a) defined by a part of the peripheral side surface. Each light-emitting unit further includes a light source (2) adjacently disposed to face the light-entrance surface to emit light into the lightguide plate through the light-entrance surface. The light-emitting units are arranged in a plurality of mutually adjacent rows with the light-exiting surfaces (3a) of their respective lightguide plates being substantially flush with each other. Adjacent rows of the light-emitting units are displaced relative to each other in the direction of the rows.Type: GrantFiled: May 26, 2009Date of Patent: June 5, 2012Assignee: Citizen Electronics Co., Ltd.Inventors: Takashi Shimura, Taku Kumasaka
-
Patent number: 8154688Abstract: A planar light-emitting device has a plurality of light-emitting units each including a light source and a lightguide plate. The light-emitting units are arranged with the light-exiting surfaces of their respective lightguide plates being substantially flush with each other. Each lightguide plate has an upper surface as a light-exiting surface, a lower surface opposite to the light-exiting surface, and a peripheral side surface extending between the respective peripheral edges of the upper and lower surfaces. The lightguide plate emits light received from the light source from the light-exiting surface. At least a part of the peripheral side surface is an inclined surface inclined relative to the light-exiting surface.Type: GrantFiled: May 26, 2009Date of Patent: April 10, 2012Assignee: Citizen Electronics Co., Ltd.Inventors: Takashi Shimura, Taku Kumasaka
-
Patent number: 8077272Abstract: A planar light-emitting device has a plurality of light-emitting units each having a lightguide plate having an upper surface as a light-exiting surface, a lower surface opposite to the light-exiting surface, a peripheral side surface extending between the respective peripheral edges of the upper surface and the lower surface, and a light entrance surface defined by a part of the peripheral side surface. Each light-emitting unit further has a light-emitting set adjacent to the light entrance surface to emit light into the lightguide plate through the light entrance surface, and a support member that fixedly supports the light source and the lightguide plate. The light-emitting units are arranged side by side so that the light-exiting or upper surfaces of their respective lightguide plates are substantially flush with each other.Type: GrantFiled: May 1, 2009Date of Patent: December 13, 2011Assignee: Citizen Electronics Co., Ltd.Inventors: Takashi Shimura, Taku Kumasaka
-
Publication number: 20100141867Abstract: A planar light-emitting device enabling reduction in the deflection of a sheet-shaped light-diffusing element includes a reflector having an upper surface serving as a light-reflecting surface, a partition provided on the reflector to extend upward to form a plurality of enclosed spaces over the upper surface of the reflector, light sources disposed in the enclosed spaces, respectively, and at least one sheet-shaped light-diffusing element supported on the upper edges of the partition to transmit and diffuse light from the light sources upward. The side surfaces of the partition that define the enclosed spaces are light-reflecting surfaces.Type: ApplicationFiled: December 3, 2009Publication date: June 10, 2010Inventors: Takeshi OGIHARA, Daisaku Okuwaki, Makoto Yasuhara, Taku Kumasaka
-
Publication number: 20100007819Abstract: A planar light-emitting device enabling more precise local dimming has a plurality of light-emitting units each including a lightguide plate and a plurality of light sources disposed successively in the lateral width direction of the light-entrance surface and adjacently facing a light-entrance surface of the lightguide plate to emit light into the lightguide plate through the light-entrance surface. The light sources are divided into a plurality of groups successively arranged in the width direction, each group including at least one light source. The lightguide plates of the light-emitting units are mutually adjacently disposed with their light-exiting surfaces being flush with each other. The planar light-emitting device has a light source output control unit that controls the outputs of the light sources for each group.Type: ApplicationFiled: July 8, 2009Publication date: January 14, 2010Inventors: Taku KUMASAKA, Daisaku OKUWAKI
-
Publication number: 20090290094Abstract: A planar light-emitting device allowing for high luminance uniformity has a plurality of light-emitting units (4), each including a lightguide plate (3) having a light-exiting surface, an opposite surface opposite to the light-exiting surface, a peripheral side surface extending between the respective peripheral edges of the light-exiting surface and the opposite surface, and a light-entrance surface (3a) defined by a part of the peripheral side surface. Each light-emitting unit further includes a light source (2) adjacently disposed to face the light-entrance surface to emit light into the lightguide plate through the light-entrance surface. The light-emitting units are arranged in a plurality of mutually adjacent rows with the light-exiting surfaces (3a) of their respective lightguide plates being substantially flush with each other. Adjacent rows of the light-emitting units are displaced relative to each other in the direction of the rows.Type: ApplicationFiled: May 26, 2009Publication date: November 26, 2009Inventors: Takashi SHIMURA, Taku KUMASAKA
-
Publication number: 20090290093Abstract: A planar light-emitting device has a plurality of light-emitting units each including a light source and a lightguide plate. The light-emitting units are arranged with the light-exiting surfaces of their respective lightguide plates being substantially flush with each other. Each lightguide plate has an upper surface as a light-exiting surface, a lower surface opposite to the light-exiting surface, and a peripheral side surface extending between the respective peripheral edges of the upper and lower surfaces. The lightguide plate emits light received from the light source from the light-exiting surface. At least a part of the peripheral side surface is an inclined surface inclined relative to the light-exiting surface.Type: ApplicationFiled: May 26, 2009Publication date: November 26, 2009Inventors: Takashi SHIMURA, Taku Kumasaka
-
Publication number: 20090273733Abstract: A planar light-emitting device comprises a plurality of light-emitting units each including a lightguide plate and arranged adjacent to each other. Each lightguide plate has a lower surface opposite to an upper surface as the light-exiting surface and a peripheral side surface extending between the peripheral edges of the upper surface and the lower surface, a light-entrance surface being defined by a part of the peripheral side surface. The light-entrance surface and its opposite surface have first and second protruding portions extending from and along the light-entrance surface and the opposite surface, respectively. In each adjacently disposed pair of light-emitting units, the first protruding portion of the first light-emitting unit abuts against the second protruding portion of the second light-emitting unit. The light source is disposed underneath the abutting protruding portions.Type: ApplicationFiled: May 4, 2009Publication date: November 5, 2009Inventors: Takashi SHIMURA, Taku Kumasaka
-
Publication number: 20090273732Abstract: A planar light-emitting device having a plurality of lightguide plates to provide a large light-exiting surface has a plurality of light-emitting units each having a lightguide plate having an upper surface as a light-exiting surface, a lower surface opposite to the light-exiting surface, a peripheral side surface extending between the respective peripheral edges of the upper surface and the lower surface, and a light entrance surface defined by a part of the peripheral side surface. Each light-emitting unit further has a light-emitting set adjacent to the light entrance surface to emit light into the lightguide plate through the light entrance surface, and a support member that fixedly supports the light source and the lightguide plate. The light-emitting units are arranged side by side so that the light-exiting or upper surfaces of their respective lightguide plates are substantially flush with each other.Type: ApplicationFiled: May 1, 2009Publication date: November 5, 2009Inventors: Takashi SHIMURA, Taku KUMASAKA