Kuraray Co., Ltd.

Japan Atomic Energy Agency

Osamu Shinji

Toshiyuki Yoshikawa

Katsuhiro Fujita

Toshitaka Kunisawa

Katashi Saito

Tatsuya Ueda

Kouzo Yasuda

Kazuo Funazaki

Kiyoshi Oka

Ryuichi Iwakawa

Yoshio Abe

Kozo Yasuda

Minoru Sonobe

A plastic scintillating fiber includes an organic compound containing an element with a neutron cross section larger than that of hydrogen, and includes: an outermost peripheral layer containing a plastic material that emits scintillation light when it is irradiated with neutron radiation; a core having a high refractive index, disposed inside the outermost peripheral layer, and containing at least one type of fluorescent substance that absorbs the scintillation light and wavelength-converts the absorbed light into light having a wavelength longer than that of the absorbed light; and a cladding layer covering an outer peripheral surface of the core and having a refractive index lower than that of the core. A wavelength shifting fiber including the core and the cladding layer, and the outermost peripheral layer covering an outer peripheral surface of the wavelength shifting fiber are integrally formed.

Plastic scintillating fiber and its manufacturing method

A plastic scintillating fiber capable of reducing modal dispersion and improving the accuracy of identifying a position which radiation passes through. A plastic scintillating fiber includes a core and a cladding that covers an outer periphery of the core and has a lower refractive index than the core. The core uniformly contains a radiation-emitting fluorescent agent and has a refractive index distribution where the refractive index of the core is highest at a center of a cross-section and becomes lower in a parabolic manner with distance from the center toward an outer periphery.

Plastic scintillating fiber and method of manufacturing the same

The object of the present invention is to provide a plastic image fiber having a small optical transmission loss. The plastic image fiber comprises N (where N is an integer equal to or greater than 2) number of cores which are disposed within a cladding. The each of the cores has an index of reflection that continuously changes at a peripheral part of the core. The index of reflection at the peripheral part on a center side of the core is greater than an index of reflection at the peripheral part on a cladding side.

Plastic image fiber and method for fabrication of same

A cable with a scintillation fiber having high radiation detecting accuracy is provided. The cable comprise a protective tube, a scintillation fiber accommodated in the protective tube, and a light emission preventing element accommodated in the protective tube.

Cable and radiation measurement apparatus

Disclosed is a composite optical fiber which has high flexibility and is hard to break. The composite optical fiber comprises a larger-diameter optical fiber and smaller-diameter optical fibers each having a smaller diameter than that of the larger-diameter optical fiber, wherein the larger-diameter fiber and the smaller-diameter optical fibers are so arranged that the larger-diameter fiber is surrounded by the smaller-diameter optical fibers, and the smaller-diameter optical fibers that surround the larger-diameter optical fiber are made from a plastic material.

Composite optical fiber and method of manufacturing the same

In a method of manufacturing a plastic optical fiber by heating and drawing either one end portion of a transparent plastic rod, a plastic optical fiber having a cross sectional form approximately similar to the cross sectional form of the transparent plastic rod, the transparent plastic rod is heated by exposing near infrared ray which is radiated from a near infrared ray source. This can prevent the plastic optical fiber from causing to blow many bubbles on the surface and heat degradation to allow the plastic optical fiber to be obtained with a high quality.

Method of manufacturing plastic optical fiber

A transmission type screen is disclosed. The transmission type screen comprises a Fresnel lens sheet, a lenticular lens sheet provided with convex black stripes on the light-exit surface, and a diffusion sheet having an uneven surface on one side thereof. In the transmission type screen, the uneven surface of the diffusion sheet is joined to the lenticular lens sheet at the top portions of black stripes.

Transmission type screen

A lenticular lens sheet that is bonded to a front faceplate and used in a rear projection type screen is disclosed. The lenticular lens sheet has a plurality of lenticular lenses arranged on one surface of a light-transmitting substrate, and projecting non-convergence parts arranged on the other surface of the light-transmitting substrate in positions different to positions of convergence of light from the lenticular lenses. An external light absorbing layer that absorbs external light is provided on a summit portion of each of the projecting non-convergence parts. Also, the lenticular lens sheet and the front faceplate are bonded together at the summit portions of the projecting non-convergence parts using an adhesive, and the width of adhesive layers formed through curing of the adhesive is less than the width of the external light absorbing layers. Consequently, the adverse effects caused by blockage of light are prevented.

Lenticular lens sheet, rear projection type screen, and method of manufacturing lenticular lens sheet

Provided is a lenticular lens sheet on which external light reflection is greatly reduced and which gives high-contrast sharp images. The lenticular lens sheet has a plurality of lenticular lenses formed on one surface of a light-transmissive substrate and having, on the other surface of the substrate, convex lenses , and external light-absorbing ridges as formed alternately with those convex lenses and coated with an external light-absorbing layer on their tops, in which every furrow between each convex lens and each external light-absorbing ridge that ate adjacent to each other is further coated with an external light-absorbing layer . The external light-absorbing layer may be not only on the top of each ridge but also around each ridge adjacent to the top thereof.

Lenticular lens sheet and method for producing it

A lightguide which guides light from at least one side end plane and includes a plurality of approximately trapezoidal protrusions whose apex edge in the cross section perpendicular to the axis of a linear light source has a partially straight section. The approximately trapezoidal protrusions are arranged on the rear surface of the lightguide, opposing a light emitting surface. The approximately trapezoidal protrusions are arranged in a pattern of specks, solid lines, or broken lines. The pattern has a low area density in a region neighboring the at least one side end plane and at a high area density in a region removed from the at least one side end plane such that the luminance distribution of the light emitted from the light emitting surface is approximately uniform. Preferably, the approximately trapezoidal protrusions have, in the same cross section, two rounded corners, and the roughness of the surface that includes the apex edge of the protrusions, the roughness of the rear surface excluding the protrusions, is less than 0.2 &mgr;m, the ratio of the height H to the width W of the approximately trapezoidal protrusions in the same cross-section be 0.1&lE;H/W&lE;0.6, and the width W is 20 &mgr;m&lE;W&lE;200 &mgr;m.

Lightguide

A transparent lightguide (,) which guide light at least from one side end plane is characterized in that a large number of speckled, solid-line shaped or broken-line shaped protruding patterns whose cross-sectional width W (&mgr;m) at a cross section perpendicular to the axis of a linear light source is 10&lE;W&lE;200 are arranged on a light emitting surface at a low density in a region close to the linear light source and at a high density in a region far from the linear light source so as to make the luminance distribution of the light emitted from the light emitting surface approximately uniform. Here, the cross section of the protruding pattern is preferable to be approximately trapezoidal while having a straight part partially and the ratio H/W to be 0.2&lE;H/W&lE;1.0, where W and H denote cross-sectional width and height of the protruding pattern, respectively, or the cross section of the protruding pattern is preferable to be approximately circular-arc and the ratio H/W to be 0.2&lE;H/W&lE;0.5, where W and H denote cross-sectional width and height of the protruding pattern, respectively.

Lightguide having trapezoidally-shaped main body with a level surface at an angle to a rear surface

The present invention includes the steps of forming a stamper with a fine and delicate relief pattern formed thereon by forming a photo resist layer on a flat substrate, exposing the photo resist, developing the exposed photo resist, metallizing and electroforming the surface of the photo resist, and of injection molding the light-transmitting plate using said stamper.

Growing community of inventors

Tainai, Japan

Osamu Shinji