Mitsubishi Gas Chemical Company, Inc.

Fuji Electric Co., Ltd.

Tomoegawa Paper Co., Inc.

Hirakawa Hewtech Corporation Mitsubishi Gas Chemical Company, Inc.

Kuniaki Jinnai

Yasunari Kawabata

Michio Ohba

Hisashi Ohwada

Norio Takeda

Mitsuzo Arii

Toshihiko Takano

Takeshi Kobayashi

Kensaku Higashi

Nobuhiko Tsuji

Michio Oba

Osamu Kondoh

Fumito Kuramochi

Hamaho Hashimoto

Hiroshi Ukaji

Tomoko Kondoh

Toshihiiko Takano

Shigeo Kataoka

A WDM optical transmission system in which a retiming unit disposed at the front stage of the optical signal supplying unit of an optical transceiver is provided. The pulse width distortion of an optical signal generated in optical transmission through an optical fiber between two WDM optical transmission apparatus is corrected by the retiming unit after the optical signal has been demultiplexed and converted into an electrical signal.

WDM optical transmission system

A wavelength division multiplexing device which can easily utilize existing optical fibers for increasing the transmission capacity by approximately several fold mainly in a short-range information communication network, comprising, as essential elements, a pair of 1&times;N optical couplers (2&lE;N&lE;16), N light emission devices in which one of peak wavelengths thereof differs from every other one by at least 30 nm and N light receivers having optical filters having light-transmission wavelength bands adjusted to correspond to said peak wavelengths, wherein the light emission devices and the light receivers having optical filters corresponding to peak wavelengths of the light emission devices form pairs, and said light emission devices of said light receivers are optically connected to N-port-side ports of one of the 1&times;N optical couplers.

Wavelength division multiplexing device

A flexible polymer optical waveguide device which is excellent in mechanical strength and durability against environments, particularly excellent in heat and chemical resistance, with maintaining characteristics of an optical waveguide and which can be easily produced, and a process for the production thereof, the flexible optical waveguide device having a structure in which a cured resin layer is formed on at least one surface of an optical waveguide film obtained by forming a refractive index distribution in a light-permeable polymer film, the cured resin layer(s) comprising a polyamide resin and at least one of an epoxy resin and a phenolic resin as main components.

Flexible optical waveguide device and process for the production thereof

A reflective type optical signal distributor comprising, in a housing (2), a plurality of optical input/output units (3) functioning as input and output terminals for an optical signal, an optical circuit assembly (6) for reflecting and separating the optical signal, and a plurality of guide optical fibers (8) for connecting the plurality of optical signals entering any one of the plurality of optical input/output units (3) and the optical circuit assembly (6), whereby an optical input/output units (3) is substantially equally distributed to all other ones of the plurality of optical input and output units (3), the optical circuit assembly (6) comprising an optical circuit in which a plurality of independent branched optical waveguides (22) merge into a single main optical waveguide (21), a reflective surface (4) formed at an end of the main waveguide (21), and the plurality of guide optical fibers (8) being connected to the corresponding plurality of independent branched optical waveguides (22).

Optical signal distributors

An optical waveguide module having a main-line waveguide, which is excellent in optical branching properties, important properties of a bus communication network, and the reproducibility of the above branching properties and is easy to produce, and an optical transmission equipment having the above optical waveguide module. The optical waveguide module having a main-line waveguide which is connected to the optical transmission path and works as part of the optical transmission path and a pair of branch waveguides (21,22) which are unidirectionally branched from the main-line waveguide, the main-line waveguide and the branch waveguides being formed by providing an optically transparent polymer film with a refractive index distribution, a light-receiving device (25) being connected to one (21) of a pair of the branch waveguides, a light-emitting device (26) being connected to the other (22).

Optical waveguide module having main-line waveguide and branch

The present invention provides a curved optical waveguide with reduced loss. Particularly, it relates to a waveguide with rectangular cross-section which has a curved portion, wherein the relation between the width D of the waveguide at the curved portion and the radius R of the curvature is R/D.ltoreq.500. This waveguide is provided with at least one cladding inside the core of said curved portion, thereby dividing the waveguide at the curved portion in a plurality of narrow optical waveguides. This enables a large reduction of the loss even in curved optical waveguides with sharp curves, and realizes inexpensive optical waveguides.

Curved optical waveguide and method of manufacturing the same

An optical waveguide having stable low branching ratio is disclosed, which includes a primary optical waveguide portion coupled at a input end thereof to an input-side optical fiber. branched optical waveguide portions each having one end continuously connected to a output end of the primary optical waveguide portion and the other ends coupled to a plurality of output-side optical fibers and an introductory waveguide portion coupled to the input end of the primary optical waveguide portion and having a width substantially identical with a core diameter of the input-side optical fiber. Further, there is provided a method of producing an optical branching device in which the optical waveguide is formed.

Optical waveguide

An optical fiber array, wherein a plurality of optical fibers are inserted between a pair of substrates consisting of a first substrate, wherein a parallel groove is formed at one end thereof for accommodating the ends of portions of a plurality of optical fibers where no covering portions are formed, an approximately rectangular groove is formed at the other end thereof for accommodating the portions of said optical fibers where covering portions are formed, and a tapered groove is formed which connects from said parallel groove towards the approximately rectangular groove whilst rectangular groove is formed at said other end thereof for accommodating the portions of said optical fibers where covering portions are formed.

Optical fibre array and method for manufacturing same

The present invention is an optical device including an optical circuit in which a plurality of branched optical waveguides are connected to a light receiving side and a light ejecting side of a main optical waveguide which mixes the entering light. The branched optical waveguides include a beginning and a terminal end. The terminal end is connected to an optical fiber and the beginning end is connected to the main optical waveguide. At least one of the branched optical waveguides has a slope or taper construction which is wider at the terminal end than at the beginning end, in order to improve lost variance and to reduce loss of light signals. The present invention also provides a method for manufacturing the above-described optical device to be used in optical local networks and optical instrumentation control systems.

Design and manufacture of an optimized waveguide-type multiple branched

An optical divider for multimode optical fibers of graded-index (GI) type composed of an optical input section for securing input optical fiber, a branching section including an optical waveguide having rectangular sectional shapes irrespective of a kind of material or a method of fabricating the same and consists of a main optical waveguide and branch waveguide, and an optical output section for securing an array of output optical fibers, wherein the main optical waveguide having a width D and a length M is divided contiguously into N branch optical waveguides, preferably three or more having uniform width W, the optical waveguide having substantially uniform core thickness T is specifically related with the core diameter K of the otpical fiber to fufull the following relational formulas:

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Tokyo, Japan

Kuniaki Jinnai