Fujikura Limited

National Institute for Materials Science

Ryuji Suzuki

Kuniharu Himeno

Kazuhiko Aikawa

Shogo Shimizu

Masakazu Nakayama

Kyosuke Takemoto

Naoto Hirosaki

Ning Guan

Ken Sakuma

Naoki Kimura

Masakazu Ohashi

Takaaki Suzuki

An LED with a semiconductor light emitting element that emits a blue or a blue-violet light, and a fluorescent material that absorbs some or all of the light emitted from the element and emits a fluorescent light of a wavelength different from the absorbed light. The fluorescent material is a mixed fluorescent material obtained by mixing a first fluorescent material that emits a blue-green or a green light, a second fluorescent material that has a peak emission wavelength longer than that of the first fluorescent material and emits a green or a yellow-green light, a third fluorescent material that has a 1 peak emission wavelength longer than that of the second fluorescent material and emits a yellow-green, a yellow or a yellow-red light, and a fourth fluorescent material that has a peak emission wavelength longer than that of the third fluorescent material and emits a yellow-red or a red light.

Light emitting device and illumination device

An enamel substrate for mounting light emitting elements includes a core metal, an enamel layer that is covering on a surface of the core metal, and one or more through holes. In this enamel substrate for mounting light emitting elements, the core metal is exposed at inner surfaces of the through holes.

Enamel substrate for mounting light emitting elements, light emitting element module, illumination apparatus, display apparatus, and traffic signal

In accordance with the present invention, a light-emitting element mounting board is provided including an enamel layer which covers the surface of a core metal, wherein reflective cup portions for mounting light-emitting elements are provided on one face of the board, and wherein a heat radiating part is formed by at least partially removing the enamel layer on the other face of the board, and exposing the core metal. Further, a light-emitting element module including light-emitting elements mounted thereon, a lighting device including the light-emitting element, a display device, and traffic signal equipment are provided.

Light-emitting element mounting board, light-emitting element module, lighting device, display device, and traffic signal equipment

A connection method for a photonic crystal fiber for connecting the photonic crystal fiber and a fiber to be connected, the photonic crystal fiber including a cladding region having a number of microholes and a core region having a same refractive index as that of the cladding region, includes the steps of: abutting respective end faces of the photonic crystal fiber and the fiber to be connected each other; after the abutting, performing a main discharge in which an abutted portion is heated by an electric discharge under a first condition; and after the main discharge, performing an additional discharge in which the connection portion is heated by an electric discharge at least once under a second condition to increase a splice strength.

Connection method and connecting structure for photonic crystal fiber

A dispersion-compensated optical fiber which does not cause an increase in a loss if it is wound in a small reel and has a stable temperature characteristics is provided, wherein, in a wavelength range from. A dispersion-compensated optical fiber is formed such that, in at least a wavelength between 1.53 to 1.63 &#x3bc;m, a bending loss of with a 20 mm bending diameter is 5 dB/m or lower, a wavelength dispersion is &#x2212;120 ps/nm/km or lower, a cut-off wavelength under a usage condition is 1.53 &#x3bc;m or lower, an outer diameter of the cladding is 80 to 100 &#x3bc;m, an outer diameter of a coating is 160 to 200 &#x3bc;m, and a viscosity of a surface of a coating resin is 10 gf/mm or lower. It is set such that b/a is 1.5 to 3.5, c/b is 1.2 to 2.0, a radius of a core is 4 to 8 &#x3bc;m, &#x394;1 is +1.6% to +2.6%, &#x394;2 is &#x2212;0.30% to &#x2212;1.4%, and &#x394;3 is &#x2212;0.30% to +1.0%. Young's modulus of a first coating layer is 0.15 kgf/mm2 or lower and its thickness is 20 to 30 &#x3bc;m. Young's modulus of a second coating layer is 50 kgf/mm2 or lower and its thickness is 15 to 30 &#x3bc;m.

Dispersion compensating optical fiber

A dispersion compensating fiber module which, when connected to an optical fiber which exhibits, at a wavelength of 1.55 &#x3bc;m, a chromatic dispersion of between +2 and +6 ps/nm/km, a dispersion slope of between +0.075 ps/nm/km and +0.095 ps/nm/pm, and a relative dispersion slope of between 0.016 nmand 0.024 nm, performs compensation so that the residual dispersion of the connected optical fiber is reduced, the dispersion compensating fiber module includes a dispersion compensating fiber and at least one optical fiber fused to the dispersion compensating fiber, in which the dispersion compensating fiber module exhibits at a wavelength of 1.55 &#x3bc;m, a relative dispersion slope of between 0.016 nmand 0.026 nm; and in a wavelength range between 1.525 &#x3bc;m and 1.565 &#x3bc;m, a maximum residual dispersion difference, when converted per km of the transmission optical fiber, of less than or equal to 0.4 ps/nm/km.

Dispersion compensating fiber module, and optical fiber transmission line

A dispersion compensating fiber, which has a negative dispersion slope with a large absolute value while maintaining the absolute value of the chromatic dispersion, and which has sufficient dispersion slope compensation properties even for the non-zero dispersion shifted optical fiber requiring a large RDS for dispersion compensation. In this dispersion compensating fiber, the radius of a ring core region is set in a range from 6.7 &#x3bc;m to 10.7 &#x3bc;m, the radius ratio of a depressed core region relative to a central core region is set in a range from 2.0 to 3.0, and the radius ratio of the ring core region relative to the depressed core region is set in a range from 1.3 to 2.0, the relative refractive index difference of the central core region relative to the cladding is set in a range from +1.00% to +1.80%, the relative refractive index difference of the depressed core region relative to the cladding is set in a range from &#x2212;1.20% to &#x2212;1.50%, and the relative refractive index difference of the ring core region relative to the cladding is set in a range from +0.20% to +0.50%.

Growing community of inventors

Sakura, Japan

Ryuji Suzuki