Nippon Sheet Glass Company, Limited

National Institute of Advanced Industrial Science and Technology

Ngb Corporation

Shigeo Kittaka

Keiji Tsunetomo

Kazuaki Oya

Tatsuhiro Nakazawa

Masatoshi Nara

Jun Yamaguchi

Minoru Toyama

Junji Nishii

Minoru Taniyama

Kiyosumi Fujii

Takahiro Asai

Hiroyuki Tanaka

Takashi Fukuzawa

Tadashi Koyama

Hideshi Nagata

Hiroshi Koshi

Hiroyuki Nemoto

Kenjiro Hamanaka

Kentaro Yamada

Takahiro Hashimoto

Takeshi Ishimaru

Masahiro Oikawa

Tetsuro Yoshii

Shinji Kawamoto

Yoshikazu Kaite

Yasuji Sasaki

Noboru Akazawa

Vladimir V Serikov

Leandro De Castro

Masami Kitano

Ikuto Ohyama

Nobuo Shibayama

Koji Kakimoto

Yoshinori Shiotani

Atsushi Akiba

A fluorescence light detection device includes an excitation light fiber having an excitation light emitting end configured to emit excitation light; a fluorescence light fiber having a fluorescence light incident end on which fluorescence light is incident; an objective lens arranged between where the excitation light emitting end and the fluorescence light incident end are located, and a sample; and a reflective member arranged between where the excitation light emitting end and the fluorescence light incident end are located, and the objective lens, and having two reflective surfaces facing in opposite directions. The two reflective surfaces of the reflective member are positioned between an optical axis of the excitation light fiber and an optical axis of the fluorescence light fiber.

Fluorescence light detection device and fluorescence light detection method

A waveguide elementincluding a photonic crystal waveguide including a corethat is constituted by a photonic crystal having a refractive index periodicity at least in one direction, and that propagates an electromagnetic wave in a direction in which the photonic crystal does not have the refractive index periodicity. At least one of materials forming the coreconstituted by the photonic crystal, and at least a portion of a cladding in contact with a side face of the coreare constituted by a fluid. Thus, it is possible to provide a waveguide element that can be used as a light control element, can be produced easily and also can be applied to an optical sensor.

Waveguide element, method for producing the waveguide element, and optical sensor

A transmissive diffraction grating includes a substrate and a plurality of ridges provided in a mutually parallel manner at constant periodicity p on the substrate. The ridges include a first layer, a second layer (refractive index n: 2.0-2.5), and a third layer with non-continuous refractive indices, arranged in that order from the substrate outward. The first layer adjacent the substrate, in terms of its refractive index, exhibits a difference of 0.1 or less relative to the substrate. The second layer has a higher refractive index than the first layer and third layer and satisfies the following conditions. For a single ridge, the cross-sectional area S of a cross-section of the second layer perpendicular to the longitudinal direction of said ridge is in the range of 0.75pk&#x3b8;/(n&#x2212;1)&#x3c;S&#x3c;1.20pk&#x3b8;/(n&#x2212;1), were, &#x3b8; is the angle of incidence onto the diffraction grating face, expressed in radian units, and the constant kis 1.1. The thickness dof the second layer is in the range of 0.70pk&#x3b8;n/(n&#x2212;1)&#x3c;d&#x3c;1.30pk&#x3b8;n/(n&#x2212;1), where, the constant kis 0.69.

Transmissive diffraction grating, and spectral separation element and spectroscope using the same

An optical waveguide deviceis configured to include a straight waveguideand bottleneck portionsprovided in two locations in the longitudinal direction of the waveguide. In the optical waveguide device, light confinement is implemented in all surfaces. This permits provision of an optical waveguide device, wherein a reflector or resonator can be provided in a waveguide using a simple configuration.

Optical waveguide device

A waveguide element using a photonic crystal having a refractive index periodicity in one direction is provided with an input portion causing propagation light due to a band on a Brillouin zone boundary within the photonic crystal.

Waveguide element using photonic crystal

An optical element of the present invention includes a structure having at least one convex portion and at least one concave portion formed so as to be adjacent to either one of the convex portions. At least one surface of the structure is covered, and the optical element has a hollow portion. At least one surface of the structure is covered with a covering layer formed by a deposition process.

Optical element, optical circuit provided with the optical element, and method for producing the optical element

A method for producing an aspherical structure according to the invention includes the steps of: forming a layer on a surface of a substrate so that the layer exhibits an etching rate distribution in a direction perpendicular to the surface of the substrate; forming a mask having a predetermined opening shape on the surface of the layer; and etching the layer to thereby form at least one aspherical concave portion. When each concave portion is used as a molding tool so that a resin with which the concave portion is filled is solidified and removed from the concave portions an aspherical lens array can be formed accurately.

Method for producing aspherical structure, and aspherical lens array molding tool and aspherical lens array produced by the same method

A photonic crystal waveguide and a homogeneous medium waveguide for enabling a steep bend and arrangement at an arbitrary angle with low propagation loss. A photonic crystal waveguide has a core formed by a photonic crystal having periodicity in the Y-direction. Electromagnetic wave is propagated by a band on the Brillouin zone boundary of the photonic band structure of the core. A side face of the core parallel to the Y-direction is in contact with a homogeneous medium having a refractive index of n, and the condition of &#x3bb;/n&#x3e;a&#x3bb;/(&#x3bb;/4+a)is satisfied when the wavelength in vacuum of the electromagnetic wave is represented by &#x3bb;, the period of the photonic crystal is represented by a, and the period in the XZ-plane direction of the wave propagated through the core is represented by &#x3bb;.

Photonic crystal waveguide, homogeneous medium waveguide, and optical device

A wavelength separator includes a one-dimensional photonic crystal structure formed by providing a plurality of grooves in parallel with one another at uniform intervals in a homogeneous medium, and has an incident end face formed obliquely with respect to a direction in which the grooves extend, and an output end face formed approximately perpendicular to the incident end face.

Optical element and wavelength separator using the same

In a waveguide element using a photonic crystal including a core formed of a photonic crystal having a refractive index periodicity in at least two directions perpendicular to a propagation direction of an electromagnetic wave and a cladding arranged in contact with the core in order to confine the electromagnetic wave in the core, an incident side phase modulation portion is provided for allowing an electromagnetic wave that is coupled to a band on or near a Brillouin zone boundary in a photonic band structure in the core and propagates in the core to enter the core.

A filter module is provided for an optical communications system. The filter module includes a lens, three optical fibers, an optical filter, and a mirror. The three optical fibers are arranged on a single side of the lens. The lens includes a first face coated with the optical filter and that faces the mirror. The optical fibers are arranged on a second face of the lens. A cascade of the filter modules are configured to connect and form a multiplexing/demultiplexing unit.

Filter module

A spectrometer using a diffraction grating includes a light-incident portion including an incident-side optical waveguide emitting a light beam that includes a plurality of wavelength components and that approximates a Gaussian beam, and a collimating lens that is arranged on an emission side of the incident-side optical waveguide and that converts the light beam approximating a Gaussian beam that is emitted from the incident-side optical waveguide into a substantially collimated light beam; a diffraction grating having grooves on its surface, on which the light beam that has been converted into the substantially collimated light beam by the collimating lens is incident, the diffraction grating spectrally separating the light beam by emitting light beams whose emission direction depends on their wavelength; and a light-emitting portion having a plurality of focusing lenses that respectively condense the light beams that have been spectrally separated by the diffraction grating.

Spectrometer using diffraction grating

An optical element, composed of an one-dimensional photonic crystal of a triangular prism shape and a multilayer film and a phase modulation unit are used together, with the phase modulation unit adjacent or abutting to a light input end surface of the optical element. Input light is phase-modulated by the phase modulation unit in the same period and direction as those of photonic crystal so that only specific high-order band light can be propagated through the optical element. When this optical element is formed in an optical waveguide, a small-size spectroscopic device having high resolving power can be provided.

Optical element using one-dimensional photonic crystal and spectroscopic device using the same

An optical imaging system is provided that includes a rod lens array and has the optimum refractive index distribution for achieving a high resolving power. The refractive index distribution of rod lenses can be expressed by()&#xb7;{1&#x2212;()&#xb7;()19 ()&#xb7;()}Eq. 45where r is a radial distance from the optical axis of the rod lenses, nis a refractive index on the optical axis of the rod lenses, and g, h, hand hare refractive index distribution coefficients. The refractive index distribution coefficients h, hand hare set on a spheroid in a Cartesian coordinate system with hbeing x-axis, hbeing y-axis and hbeing z-axis. The spheroid is defined by a vector X* that is expressed by()=Eq. 46where O* is a vector from the origin of the Cartesian coordinate system to the center of the spheroid, A*, B* and C* are vectors in the directions of the major axis, the mean axis and the minor axis of the spheroid, respectively, and k, kand ksatisfy k+k+k&#x2266;1.

Optical imaging system with rod lens array

An optical element according to the invention constituted by a multilayer structure having a periodic structural portion as at least one region constituted by repetition of a predetermined period, wherein an end surface of the multilayer structure not parallel to layer surfaces of the multilayer structure is used as a light input surface whereas one or each of opposite surfaces of the multilayer structure parallel to the layer surfaces is used as a light output surface. There is an intermediate layer between a medium and a surface of the multilayer structure, the intermediate layer having a refractive index less than the refractive index of the medium. The periodic structural portion of the multilayer structure can be regarded as a one-dimensional photonic crystal. Refracted light from the one-dimensional photonic crystal has good directivity and the direction of the refracted light has strong dependence on wavelength. When this wavelength dependence property is used, a spectroscopic device or a polarized light separating device of high resolution can be achieved without increase in device size.

Growing community of inventors

Osaka, Japan

Shigeo Kittaka