1
Takayuki Mizuno, Tsutomu Kitoh, Yasuyuki Inoue, Yoshinori Hibino, Mikitaka Itoh, Takashi Saida, Yasuhiro Hida: Planar lightwave circuit and optical circuit. Nippon Telegraph and Telephone Corporation, Kenyon & Kenyon, August 30, 2005: US06937797 (11 worldwide citation)

A planar lightwave circuit is provided. The planar lightwave circuit includes a waveguide and a spotsize converter which is a part of the waveguide, wherein a core is embedded in a cladding in the waveguide, and the spotsize converter is located near an end face of a substrate on which the planar li ...


2
Akio Sugita, Akimasa Kaneko, Mikitaka Itoh: Planar lightwave circuit. Nippon Telegraph and Telephone Corporation, Blakely Sokoloff Taylor & Zafman, October 16, 2001: US06304706 (8 worldwide citation)

This planar lightwave circuit includes a buried layer formed in a region between at least two cores branching from a branching point to decrease in thickness as the spacing between the cores increases with an increase in distance from the branching point. The planar lightwave circuit is designed to ...


3
Toshimi Kominato, Akio Sugita, Mikitaka Itoh, Yasuyuki Inoue, Yasuhiro Hida: Optical waveguide circuit. Nippon Telegraph and Telephone Corporation, Kenyon & Kenyon, June 17, 2003: US06580862 (6 worldwide citation)

An optical waveguide circuit is provided that can reduce or eliminate polarization dependence by reducing or eliminating birefringence. A substrate consists of a silicon substrate, and a cladding and a core are composed of silica-based glass. The core has a multilayer structure composed of a few typ ...


4
Shin Kamei, Tsutomu Kitoh, Masaki Kohtoku, Tomohiro Shibata, Takuya Tanaka, Yasuyuki Inoue, Mikitaka Itoh: Optical wavelength multiplexing/ de-multiplexing circuit. Nippon Telegraph and Telephone Corporation, Workman Nydegger, February 5, 2013: US08369666 (4 worldwide citation)

An optical wavelength multiplexing/de-multiplexing circuit having a low loss and a flat transmission spectrum is provided. The optical wavelength multiplexing/de-multiplexing circuit compensates a temperature dependence of a center transmission wavelength which remains in an athermal AWG, and has an ...


5
Mikitaka Itoh, Ryoichi Kasahara, Takashi Saida, Yasuhiro Hida: Optical waveguide and fabricating method thereof, and optical waveguide circuit. Nippon Telegraph and Telephone Corporation, Darby & Darby, September 23, 2003: US06625370 (4 worldwide citation)

An optical waveguide and an optical waveguide circuit having polarization insensitivity or a required low-level polarization dependence without degradation of the optical characteristics and reliability are disclosed, and a fabricating method of an optical waveguide and an optical waveguide circuit ...


6
Mikitaka Itoh, Takashi Saida, Yasuhiro Hida, Yasuyuki Inoue: Silica-based optical waveguide circuit and fabrication method thereof. Nippon Telegraph and Telephone Corporation, Workman Nydegger, August 10, 2004: US06775454 (2 worldwide citation)

A silica-based optical waveguide circuit serves to reduce the time required to production while allowing a spot size converting function to work sufficiently. In a silica-based optical waveguide circuit comprising an input/output waveguide core formed to be thicker than an waveguide core and a taper ...


7
Shin Kamei, Yasuyuki Inoue, Mikitaka Itoh: Arrayed waveguide grating. Nippon Telegraph and Telephone Corporation, Workman Nydegger, October 21, 2014: US08867873 (1 worldwide citation)

An optical wavelength multi/demultiplexing circuit is provided in which temperature dependence at a transmission center wavelength remained in an athermalized AWG is compensated. An AWG according to an embodiment of the present invention is compensated for the main temperature dependence at the tran ...


8
Takanori Ishikawa, Tomoyo Shibazaki, Mitsuru Nagano, Masahiro Yanagisawa, Hiroshi Terui, Mikitaka Itoh: Optical waveguide device and module. NTT Electronics Corporation, Nippon Telegraph and Telephone Corporation, Workman Nydegger, June 20, 2017: US09684129

In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding ...


9
Takanori Ishikawa, Tomoyo Shibazaki, Mitsuru Nagano, Masahiro Yanagisawa, Hiroshi Terui, Mikitaka Itoh: Optical waveguide device and module. NTT ELECTRONICS CORPORATION, NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Workman Nydegger, November 13, 2018: US10126502

In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding ...


10
Takanori Ishikawa, Tomoyo Shibazaki, Mitsuru Nagano, Masahiro Yanagisawa, Hiroshi Terui, Mikitaka Itoh: Optical waveguide device and module. NTT Electronics Corporation, Nippon Telegraph and Telephone Corporation, Workman Nydegger, April 28, 2015: US09020307

In a waveguide device, unnecessary optical power is appropriately terminated. According to an embodiment of the present invention, the waveguide device has a termination structure filled with a light blocking material to terminate light from a waveguide end. In the termination structure, a cladding ...