National Institute of Advanced Industrial Science and Technology

Nippon Sheet Glass Company, Limited

Agency of Industrial Science and Technology

Nihon Yamamura Glass Co., Ltd.

Non Oxide Glass Research and Development Co., Ltd.

Junji Nishii

Keiji Tsunetomo

Shigeo Kittaka

Tatsuhiro Nakazawa

Hiroshi Yamanaka

Kazuaki Oya

Takashi Yamagishi

Hidekazu Hashima

Naoyuki Kitamura

Tatsuo Hidaka

Kohei Fukumi

Junichi Nakamura

Jun Yamaguchi

Tadashi Koyama

Yoshitaka Mayumi

Adilson Oliveira Da Silva

Takahiro Inoue

Derek A H Cunningham

Ikuo Inagawa

Shozo Morimoto

Ryuji Iizuka

Noboru Tohge

Takuro Ikeda

Kenji Kintaka

A PO&#x2014;BaO&#x2014;ZnO&#x2014;NbOtype optical glass contains 25-50 wt. % PO, 15-35 wt. % BaO, 1-25 wt. ZnO, and 3-10 wt. % NbO. The optical glass has a high refractive index (particularly preferably the refractive index nof 1.6 or more), low dispersion (an Abbe number &#x3c5;of 42 or more), a low deformation point, and improved resistance to devitrification upon molding, and is suitable for precision-mold press molding or other molding processes and also suitable for transfer of a fine structure.

Optical glass

An optical glass having a high refractive index (particularly preferably a refractive index of 1.6 or more), low dispersion (an Abbe number of 45 or more), a low deformation point, and improved resistance to devitrification upon molding, and suitable for precision-mold press molding or other molding processes and also suitable for transfer of a fine structure is provided. The optical glass contains 1.0-4.5 wt. % SiO, 30.5-50.0 wt. % BO, 1.1-8.0 wt. % LiO, 10.1-19.5 wt. % BaO, 15.5-30.0 wt. % ZnO, 3.0-15.0 wt. % YO, and 10.0-19.5 wt. % LaO.

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 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

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

In homogeneous materials, etching characteristics depend on properties inherent in these materials regardless of whether they are isotropic or anisotropic, and there have been limitations in realizing various desired shapes. A subject for the invention is to provide a gradient material which eliminates these limitations. A gradient material is provided in which the rate of etching with a specific chemical substance changes continuously or by steps from the outermost surface to an inner part thereof. This gradient material is made of a main material which contains an additive capable of changing the etching rate of the main material so that the concentration of the additive changes continuously or by steps. Especially when a glass material containing SiOas the main component is used as the main material and fluorine is used as the additive, then a gradient material in which the rate of etching with an aqueous solution of hydrofluoric acid changes in the depth direction can be obtained.

Graded material and method for synthesis thereof and method for processing thereof

This invention provides a method of manufacturing a diffraction grating capable of scribing by an interference light at a lower power density than usual. That is, a coating solution containing a metal alkoxide and a &bgr;-diketone is coated on a substrate, the coated film is heat treated to form a gelled film and then an interference light is irradiated to the gelled film, to manufacture a diffraction grating.

Method of manufacturing a diffraction grating

A film containing TiO,and SiO,. It is formed by depositing TiO,and SiO,onto a substrate by sputtering method, or depositing their vapors thereon. The film is heat treated at a temperature of 200-1200&deg; C. to form a film of anatase type TiO,containing SiO,.

Film of titanium dioxide containing silicon dioxide and a method of forming the same

An optical micro-machining method of glass characterized in that after light is applied to glass including SiO.sub.2 and 30-70 mol % GeO.sub.2, the irradiated area is removed by etching.

Optical micro-machining method of glass

A glass material variable in volume by irradiation with ultraviolet light has a GeO.sub.2 --SiO.sub.2 glass composition having a GeO.sub.2 content of 0.5 to 90 mol %, and is in the form of a thin film formed in an argon atmosphere or in an argon-oxygen mixed gas atmosphere by the high-frequency sputtering method.

Glass material variable in volume by irradiation with ultraviolet light

This invention provides a method of producing a diffraction grating of a spectroscope by applying light to a thin film of glass having characteristics such that a density change occurs with the change of a glass structure upon irradiation of light and volume expansion occurs irreversibly. The method comprises applying light to a diffraction grating formation of a surface of the thin film by applying light through a phase mask or applying interference light, and causing the light irradiation portion of glass to expand and to thereby form the diffraction grating. Light to be applied is generally laser beams of ultraviolet rays, such as an excimer laser, a Nd-YAG laser or UV higher harmonics of a dye laser. A laser beam of a visible light region can be used, too. Preferably, a silica single crystal plate is used for the substrate of the thin film, and sputter vacuum deposition is used for forming the thin film. The glass composition whose volume expands upon irradiation of light is GeO.sub.2 --SiO.sub.2 type glass having a GeO.sub.2 content of 20 to 95 mol %, but this composition is not particularly limitative, and any glass compositions can be used so long as they have a high volume expansion coefficient.

Production method of diffraction grating

A process for producing a chalcogenide glass fiber which comprises placing a cylindrical chalcogenide glass preform vertically in a cylindrical crucible furnished with a nozzle in its bottom portion, heating the crucible only at vicinity of the nozzle, and continuously drawing the glass into a fiber with the temperature of the crucible at the vicinity of the nozzle being maintained at such a level that the viscosity of the glass is within the range of 10.sup.3 to 10.sup.7.5 poises.

Process for producing chalcogenide glass fiber

A method for purifying starting materials for chalcogenide glass is disclosed, which comprises contacting chalcogen starting materials at a high temperature with a metal which is more susceptible to oxidation than the chalcogen starting materials to allow the metal to react with oxygen contained as impurity in the chalcogen starting material to form an oxide of the metal, and then removing the metal and the oxide of the metal from the chalcogen starting materials.

Growing community of inventors

Ikeda, Japan

Junji Nishii