Hoya Corporation

Hoya Glass Works, Ltd.

Nippon Sheet Glass Company, Limited

Okamoto Glass Co., Ltd.

Hoya Lens Co., Ltd.

Toshiharu Yamashita

Tetsuro Izumitani

Kiyotaka Miura

Yoshitaka Yoneda

Isao Masuda

Hidemi Tajima

Shozo Morimoto

Yoshimi Fujita

Minoru Tokida

Sho Amano

Tetsuo Suzuki

Atsushi Arai

Khaled Jabri

Hiromichi Nishimura

Yoshihiko Noro

Nobuhito Takeshima

Yasuo Fukuoka

A glass polarizer having an excellent transmittance and extinction ratio with respect to light in the visible light range including blue using silver halide containing glass as a starting material is provided. A manufacturing method according to the present invention to manufacture glass polarizers is characterized in that borosilicate glass in which silver halide particles are dispersed and deposited by heat treatment is reduced to generate metallic silver particles from at least a portion of silver halide and then, heated for stretching to generate silver halide particles oriented and stretched in the glass.

Glass polarizer and manufacturing method thereof

A polarizing glass comprising geometrically anisotropic particles dispersed in an oriented manner in at least the surface of a glass base body. The glass base body is denoted by the weight percentages of 50-65 percent SiO , 15-22 percent B O , 0-4 percent Al O , 2-8 percent ZrO , 6 percent <Al O &plus;ZrO <12 percent, 6-16 percent R O (where R denotes at least one from among Li, Na, and K), 0-3 percent Li O, 0-9 percent Na O, 4-16 percent K O, Li O&plus;Na O<K O, 0-7 percent BaO and/or SrO, and 0-3 percent TiO . The glass base body comprises per 100 weight percent of essentially the above composition at least 0.15-1.0 percent Ag and at least the chemical equivalent to Ag of Cl and/or Br; and the geometrically anisotropic silver particles are metallic Ag particles. The polarizing glass is employed in optical products such as optical isolators.

Polarizing glass and preparation method thereof

Chalcogenide glass fibers having a glass core with two cladding glass layers, the second cladding glass layer having a refractive index lower than that of the core glass and higher than that of the first cladding glass. The core glass does not contain germanium. Glass fiber having this core-cladding structure is mechanically strong and exhibits only small transmission loss of infrared light passing through the fiber.

Chalcogenide glass fiber

A process for producing a preform for a chalcogenide glass fiber which comprises inserting a cladding tube having contained therein a chalcogenide glass rod for core into a quartz tube having at its bottom a nozzle having an aperture smaller than the outer diameter of the cladding tube, locally heating the bottom of the quartz tube and pulling the cladding tube having contained the glass rod for core and a process for producing a chalcogenide glass fiber by heating and drawing the preform thus obtained, by which processes the devitrification of glass and the generation of bubbles in the core glass or at the core glass-cladding glass interface can be prevented and the adhesion between the core glass and the cladding glass can be improved. In particular, when the glass material for core does not contain Ge, a chalcogenide glass fiber having such a core-cladding structure that the transmission loss of the glass fiber when infrared light pass through the fiber is small and the mechanical strength is high.

Process for producing preform for glass fiber and process for producing

In a method of manufacturing a preform for a nonoxide glass fiber, cladding and core glass materials are placed in a cylinder of an extrusion apparatus such that ground end faces of the respective cladding and core glass materials are in contact with each other and such that the cladding glass material is located adjacent a molding section of the extrusion apparatus. The cladding and core glass materials are heated within inert-gas atmosphere, to their respective temperatures equal to or below their respective sag points and equal to or above their respective crystallization start temperatures. An extrusion punch of the extrusion apparatus is pushed within the atmosphere, to extrude the cladding and core glass materials through a molding nozzle in the molding section while the cladding and core glass materials are in fusible contact with each other, thereby forming the preform of a core and cladding structure. The preform is gradually cooled within a liner connected to the molding section within the atmosphere. Alternatively, an over-cladding glass material may be placed in the cylinder such that the over-cladding material is located adjacent the molding section, and the cladding glass material is located between the over-cladding and core glass materials.

Method of manufacturing preform for nonoxide glass fiber

A single mode laser glass fiber showing excellent laser oscillation characteristics even at a short fiber length can be efficiently obtained using a phosphate laser glass with excellent laser characteristics.

Single mode phosphate laser glass fiber

The fluoride glass of the present invention, which contains, as anions, a small amount of chlorine in addition to fluorine, has advantages such as (1) it is less liable to crystallize as compared with a fluoride glass containing no chlorine and yet shows substantially no deterioration in chemical durability and mechanical strength due to chlorine inclusion and (2) its refractive index can easily be changed by changing the addition amount of chlorine.

Halide glass

A high quality fluorophosphate laser glass free from bubbles, inclusions and coloring can be obtained by melting a fluorophosphate glass having a total oxide content of 5 to 30% in terms of cationic %, in a carbon container under a non-oxygen gas atmosphere.

Method for melting fluorophosphate glass

An tinted eyeglass lens having a photochromic gradient and a process for producing the same are disclosed. The photochromic gradient is provided by changing the particle diameter of silver halide particles in the face direction of the glass.

Photochromatic gradient lens having two colortones and process for

A fluoride glass comprising AlF.sub.3, ZrF.sub.4 and/or HfF.sub.4, and at least one compound selected from CaF.sub.2, SrF.sub.2 and BaF.sub.2, and a fluoride glass comprising these components and at least one additional component selected from MgF.sub.2, YF.sub.3, NaF and other like compounds have the advantages that there hardly occurs crystallization in the production thereof, and that they are excellent in chemical durability, high in surface hardness, so that they can ideally serve as glass to be used for low loss optical fiber, infrared optical fiber for thermometer, infrared laser window, etc.

Fluoride glass

A Faraday rotation single-mode fiber having a high Verdet constant is disclosed, the core and the cladding of the fiber being made of a glass having the following composition: 26 to 38 mol % SiO.sub.2, 18 to 34 mol % B.sub.2 O.sub.3, 17 to 26 mol % Al.sub.2 O.sub.3, 18 to 32 mol % Tb.sub.2 O.sub.3, 0 to 5 mol % ZrO.sub.2, 0 to 5 mol % Ce.sub.2 O.sub.3, 0 to 5 mol % Pr.sub.2 O.sub.3, 0 to 5 mol % Dy.sub.2 O.sub.3 and 0 to 5 mol % Ho.sub.2 O.sub.3, provided that the total amount of the above ingredients is not less than 97 mol % and the total amount of Ce.sub.2 O.sub.3, Pr.sub.2 O.sub.3, Dy.sub.2 O.sub.3 and Ho.sub.2 O.sub.3 is 0 to 5 mol %.

Faraday rotation single-mode optical fiber

A glass filter for contrast enhancement in a color CRT display devices comprises

Contrast enhancement filter for color CRT display devices

A method for irradiating a chemically machinable light-sensitive glass plate with a parallel bundle of ultraviolet rays so as to form tapered holes or slits in the glass plate. A mask having a desired shaped opening is mounted on the light-sensitive glass plate and the plate is disposed so that its surface forms a predetermined angle with a plane which is perpendicular to the parallel bundle of ultraviolet rays. The glass plate is then rotated about a central vertical axis thereof.

Method for exposure of chemically machinable light-sensitive glass

A method for irradiating a chemically machinable light-sensitive glass plate with a parallel bundle of ultraviolet rays so as to form a tappered polygonal hole in the glass plate. A mask having a regular polygonal opening having n vertexes is mounted on a machinable light-sensitive glass plate and a light source capable of generating a parallel bundle of ultraviolet is disposed so that one of the vertexes of the polygonal opening is positioned at the longest point from the center of the light source. The glass plate is then irradiated. Thereafter, the light source is rotated about a center axis of the opening by an angle equal to 360.degree./n and the glass plate is re-irradiated. This procedure is conducted so that the glass plate is irradiated n times.

Method of exposure of chemically machineable light-sensitive glass

A glass for use as an optical glass having an anti-blurring property, water resistance and hardness and decreased liquidus temperature, said glass consisting essentially of, in mol. %, 47 to 65% P.sub.2 O.sub.5, 0.5 to 12% SiO.sub.2, 0.5 to 10% B.sub.2 O.sub.3, 6 to 15% SiO.sub.2 +B.sub.2 O.sub.3, 0 to 30% alkali metal oxide, 5 to 35% alkaline earth metal oxide, 20 to 45% alkali metal oxide+alkaline earth metal oxide, 0 to 5% Al.sub.2 O.sub.3, 0 to 10% ZnO, and no PbO. Oxides of Ce, Nd and Er may also be present.

Growing community of inventors

Hachioji, Japan

Toshiharu Yamashita