Mitsubishi Rayon Company, Limited

Yasuteru Tahara

Tomoyoshi Yamashita

Takashi Yamamoto

Kenichi Sakunaga

Kazuki Nakamura

Kazuyoshi Koike

Hiromu Terada

Ryuji Murata

Katsuhiko Shimada

Jun Nakauchi

Yoshihiro Uozu

Toshinori Sumi

Teruta Ishimaru

Masaharu Oda

Shunsuke Minami

Mikio Sera

Hiroshi Terada

A graded index type optical fiber having a multilayer structure comprising a plurality of concentrically arranged layers formed of (co)polymers selected from the group consisting of two or more homopolymers HP1, HP2, . . . , HPn derived from monomers M1, M2, . . . , Mn, respectively, and having refractive indices decreasing in that order, and one or more binary copolymers CP derived from these monomers, the multilayer structure being such that a mixed layer consisting of the (co)polymers constituting two adjacent layers is formed therebetween, and the refractive index is highest at the center and decreases gradually toward the outer periphery. This optical fiber can be continuously formed by feeding the (co)polymers to a multilayer concentric circular nozzle and thereby extruding them through the nozzle, and allowing the polymers to interdiffuse between adjacent layers of the fiber.

Graded index type optical fibers and method of making the same

A color image scanner is constructed by a three primary color LED array ( ) for illuminating an original ( ) to be read out, a monochromatic image sensor array ( ) and a rod lens array ( ) disposed between the original ( ) and the image sensor array ( ). The focusing parameters of the three kinds of refractive index distribution type rod lenses ( ) constituting the rod lens array ( ) are set so that each of the operating wavelength band and the predetermined wavelength is different among the kinds, the lens length Z is equal among the kinds, and the conjugate length TC at each predetermined wavelength is substantially equal among all the kinds. Accordingly, when a color image reading operation is carried out by using the rod lens array which is effective in compactness and brightness, the chromatic aberration of the rod lens array can be sufficiently reduced and high-resolution can be implemented at low cost.

Low chromatic aberration rod lens array, its unit and image scanner employing them

A graded index type optical fiber having a multilayer structure comprising a plurality of concentrically arranged layers formed of (co)polymers selected from the group consisting of two or more homopolymers HP,HP,. . . , HPn derived from monomers M,M,. . . , Mn, respectively, and having refractive indices decreasing in that order, and one or more binary copolymers CP derived from these monomers, the multilayer structure being such that a mixed layer consisting of the (co)polymers constituting two adjacent layers is formed therebetween, and the refractive index is highest at the center and decreases gradually toward the outer periphery. This optical fiber can be continuously formed by feeding the (co)polymers to a multilayer concentric circular nozzle and thereby extruding them through the nozzle, and allowing the polymers to interdiffuse between adjacent layers of the fiber.

A method and an apparatus for high-precision scattered light measurements characterized in that:

Method and apparatus for scattered light measurements

A plastic optical fiber which is superior in the light transmission characteristics, particularly in those within a visible light region and also superior in heat resistance, and a process for producing the same are provided, which plastic optical fiber comprises a polycarbonate as its core material and a polymer as its cladding material having a refractive index lower than that of the core material, wherein the relationship between the light transmission loss L.sub.500 (dB/km) of the fiber as measured at a wavelength of 500 nm and that as measured at 660 nm being expressed by the following inequality:

Plastic optical fiber and process for producing the same

Plastic optical fibers

A process for the preparation of a multifilament optical fiber having 1,000 to 10,000 islands as optical filaments, which comprises using a composite spinning spinneret for the preparation of an islands-in-a-sea type multifilament fiber, which comprises at least three piled orifice plates including an orifice plate having many island-forming nozzle holes, an orifice plate having a sea-forming nozzle hole and an orifice plate having a filament-gathering nozzle hole, the nozzle hole of the orifice plate arranged just above the lowermost orifice plate having a trumpet-shaped opening extending toward the lower end face thereof and a sea component flow passage being formed between two orifice plates arranged just above the lowermost orifice plate, and supplying a thermoplastic polymer for forming cores of optical filaments from the island-forming nozzle holes and a sea-forming thermoplastic polymer from the sea-forming nozzle hole to effect composite spinning and gathering many filaments in the gathering nozzle hole.

Process for preparation of multifilament optical fibers

An improved method and an equipment for detecting a pinhole in hollow filament, wherein the improvement comprises passing the hollow filament through a liquid maintained at a pressure higher than that of the gas in the interior of said hollow filament to allow the liquid to intrude through the pinhole into the interior of the hollow filament and detecting the intruded liquid.

Method and equipment for detecting pinholes of hollow filament

Provided is an apparatus for inspecting an optical fiber assembly through measuring irregularities in transmission loss of optical fibers which constitute said optical fiber assembly. The apparatus includes a base, a first slider block slidably laid on the base, means attached to the first slider block and adapted to grip both ends of the optical fiber assembly, a feed mechanism for feeding the first slider block by sliding the same on the base, a frame member secured to the base, a second slider block carried by the frame member, a light projector carried by the second slider block and adapted to irradiate a light beam onto the light receiving end of one of the optical fibers, a light receiver for receiving a light beam from the light emitting end of the one of the optical fibers and a light stop disposed in the light projector and adapted to stop the light beam irradiated by the light projector so that the light beam may be irradiated, exclusively, onto the light receiving end of only one of the optical fiber and within the same.

Inspection apparatus for optical fiber assembly

An improved image-transmitting synthetic resin rod comprising a reaction product of an acrylic resin .circle.1 containing epoxy groups with a material .circle.2 having a refractive index 0.15-0.35 lower than that of said acrylic resin .circle.1 , and distributed in said rod so as to satisfy equation (1):

Image-transmitting synthetic resin rod and a process for producing the

A method of and a system for detecting pinholes in hollow fibers by passing a liquid filled fiber into a zone of pressurized gas wherein the pressure of a gas is higher than that of a liquid inside the hollow fiber so that bubbles may be injected through pinholes contained in said hollow fiber and then passing the fiber through a bubble detector. The system can be operated continuously with the pinhole detector being between a device for continuously feeding the hollow fiber and a device for winding up said hollow fiber.

Method of detecting pinholes in hollow fibers

A method of measuring light transmission losses of optical materials comprising projecting light beams at two separate points alternatively or a light beam through a part of an optical material to be measured, and detecting the intensities of light radiated at two separate points lying along the direction of propagation of said light beams in said part.

Growing community of inventors

Otake, Japan

Yasuteru Tahara