A rod-in-tube method for producing a glass preform for use in the fabrication of an optical fiber, which comprises steps of inserting a glass rod (13) as a core material in a glass tube (12) as a cladding material, fusing and closing one end of the cladding material, filling a gap between the core and cladding materials with an atmosphere containing at least one gaseous halogen-containing compound and then heating the core and cladding materials at a temperature not lower than 1,900°C to collapse the gap between them and to fuse them together, from which glass preform, an optical fiber with low attenuation of light transmission is fabricated.

Method for producing glass preform for optical fiber

High index-contrast fiber waveguides, materials for forming high index-contrast fiber waveguides, and applications of high index-contrast fiber waveguides are disclosed.

High index-contrast fiber waveguides and applications

There is provided a feedback-controlled self-heat-monitoring fiber, including an insulator having a fiber length with at least one metal-semiconductor-metal thermal sensing element along the fiber length and disposed at a position in a cross section of the fiber for sensing changes in fiber temperature. An electronic circuit is connected to the thermal sensing element for indicating changes in fiber temperature. A controller is connected for controlling optical transmission through an optical transmission element, that is disposed along the fiber length, in response to indications of changes in fiber temperature.

Thermal sensing fiber devices

The invention relates to lenses, prisms or other optical members which are subjected to high-power ultraviolet light having a wavelength of about 360 nm or less, or ionizing radiation, particularly optical members for use in laser exposure apparatus for lithography, and to blanks for such optical members. The homogeneity of the refractive index distribution and the resistance to optical deterioration when the optical members are exposed for a long period of time to short wavelength ultraviolet light from a laser beam are improved. The optical members are made of high-purity synthetic silica glass material containing at least about 50 wt. ppm of OH groups, and are doped with hydrogen. The refractive index distribution caused by the fictive temperature distribution during heat treatment in the process of producing high-purity silica glass blanks for optical members in accordance with the present invention is offset by the combined refractive index distribution determined by the OH group concentration distribution or by the OH group concentration distribution and the Cl concentration distribution in the glass.

Optical members and blanks of synthetic silica glass and method for their production

A camera may be mounted under a display in an electronic device. The display may include a polarizer layer, a color filter layer, and a thin-film-transistor layer. A layer of material such as a glass insert may be attached to an edge of the display. Openings may be formed in the layers of the display and the insert to accommodate the camera. A sleeve structure may be mounted within an opening. The camera may include lens structures formed from a stack of lens elements. One or more layers of the display may be interposed within the lens structures. The glass insert may be mounted within a notch in the color filter layer and thin-film transistor layer or along a straight edge of the color filter layer and thin-film transistor layer. The edge of the color filter layer may be recessed with respect to form a mounting shelf for the insert.

Camera lens structures and display structures for electronic devices

A process for producing a glass perform for optical transmission fibers, which includes supplying a gaseous silicon compound, ammonia or a gaseous nitrogen compound, and an oxygen-containing gas as starting gases into a high temperature zone to produce fine particles of SiOxNy glass and depositing the fine particles in the form of a soot or a transparent glass on a starting member to produce nitrogen-doped silica glass.

Process for preparing glass preform for optical fiber

A method of manufacturing glass rod for optical waveguides is proposed. In this method, several gaseous mixtures or powdery mixtures of materials for glass forming are reacted at a high temperature and deposited on the top or end of a rotating glass rod which is initially deposited on a rotating base plate and grown in the form of a rod of a fixed powdery or vitreous state. It is possible to obtain the glass rod having a predetermined radial distribution of index of refraction.

Method of manufacturing glass for optical waveguide

A process for producing an optical transmission fiber is provided which comprises feeding highly pure halides, hydrides or organic compounds of Si and B by way of carrier gas on the outer surface of a fused silica rod or a fused silica pipe, or inner surface of a fused silica pipe, oxidizing them and depositing the products to form a pure fused silica layer or a doped fused silica layer containing B2 O3, melting the pipe and the deposited layer followed by a spinning. The SiO2 layer can alternatively contain fluorine instead of B2 O3. A further SiO2 layer can be deposited thereon to improve the spinning processability and lower the index of refraction of the B2 O3 containing layer.

Process for producing optical transmission fiber

An optical transmission fiber comprising (1) a core of high refractive index composed of SiO2 -based glass containing at least one of GeO2, As2 O3, Sb2 O5, SnO2, TiO2, PbO and Bi2 O3, (2) a clad of low refractive index composed of SiO2 -based glass containing at least one of B2 O3, F, F/B2 O3 and F/P2 O5, and (3) an outermost jacket layer composed of SiO2 and/or SiO2 -based glass containing at least one of Al2 O3, TiO2, ZrO2 and HfO2.

Optical transmission fiber and process for producing the same

A method for producing an optical waveguide by melt-drawing a transparent glass rod which has been produced by collapsing a porous glass rod after being doped with a dopant material by depositing said material on the surface of the micro pores in order to enhance the refractive index of the collapsed glass rod, wherein a waveguide having higher mechanical strength and lower transmission is attained by drawing said glass rod at a temperature very close to the melting point of the outermost portion of the fiber without causing any overmelting or bubbling in the core portion, said drawing being facilitates by matching the viscosity and characteristics of the outermost lower-refractive-index portion to those of the central higher-refractive-index portion.

Shiro Kurosaki

Papers

Process for preparing glass preform for optical fiber

Method of manufacturing glass for optical waveguide

Process for producing optical transmission fiber

Optical transmission fiber and process for producing the same

Method of producing optical waveguide