Abstract: Provided is a glass composition including the following components in mass %: 45?SiO2?80; 10?B2O3?40; 0.1?Al2O3?20; 0.1?(MgO+CaO)?10; 0?(Li2O+Na2O+K2O)?5; and 0.1?T-SnO2?2, where T-SnO2 represents total tin oxide calculated as SnO2, wherein 0?MgO/(MgO+CaO)?0.50 is satisfied on a mass basis. This glass composition is suitable for stably manufacturing a low-permittivity glass fiber.

Abstract: The glass composition according to the present invention is a glass composition including SiO2, B2O3, Al2O3, an alkaline-earth metal oxide and another metal oxide. When an average thermal expansion coefficient of the glass composition in a temperature range of 0° C. to T° C. is expressed as CTE (T), a relationship of (17.1×10?3×T+25.4)×10?7/° C.?CTE (T)?(17.1×10?3×T+31.4)×10?7/° C. is satisfied in a temperature range of 0° C. to 100° C.

Abstract: The present invention provides a mother glass composition for gradient-index lens, from which a lead-free Li-based gradient-index lens that is excellent in weather resistance, in particular weather resistance in the presence of water, can be manufactured. The mother glass composition includes the following components, indicated by mol %: 40?SiO2?65; 1?TiO2?10; 0.1?MgO?22; 0.15?ZnO?15; 2?Li2O?18; 2?Na2O?20; 0?B2O3?20; 0?Al2O3?10; 0?K2O?3; 0?Cs2?O?3; 0?Y2O3?5; 0?ZrO2?2; 0?Nb2O5?5; 0?In2O3?5; 0?La2O3?5; and 0?Ta2O5?5. The mother glass composition further includes at least two oxides selected from CaO, SrO, and BaO each in a range of 0.1 mol % to 15 mol %. The total of MgO+ZnO is greater than or equal to 2 mol %. The molar ratio of ZnO/(MgO+ZnO) is in a range of 0.07 to 0.93. The total of Li2O+Na2O is in a range of 6 mol % to 38 mol %. The total of Y2O3+ZrO2+Nb2O5+In2O3+La2O3+Ta2O5 is in a range of 0 mol % to 11 mol %.

Abstract: A mother glass composition for graded index lenses, comprising the following glass components in mol %: 40?SiO2?65, 1?TiO2?10, 0?MgO?22, 2?Li2O?18, 2?Na2O ?20, 6?Li2O+Na2O?38, and from 0.1 to 15 mol % of any two or more of CaO, SrO and BaO, a graded index lens using the mother glass composition, a manufacturing method of the graded index lens, and an optical product and an optical instrument using the graded index lens, are provided.

Abstract: The present invention provides a mother glass composition for gradient-index lens, from which a lead-free Li-based gradient-index lens that is excellent in weather resistance, in particular weather resistance in the presence of water, can be manufactured. The mother glass composition includes the following components, indicated by mol %: 40?SiO2?65; 1?TiO2?10; 0.1?MgO?22; 0.15?ZnO?15; 2?Li2O?18; 2?Na2O?20; 0?B2O3?20; 0?Al2O3?10; 0?K2O?3; 0?Cs2?O?3; 0?Y2O3?5; 0?ZrO2?2; 0?Nb2O5?5; 0?In2O3?5; 0?La2O3?5; and 0?Ta2O5?5. The mother glass composition further includes at least two oxides selected from CaO, SrO, and BaO each in a range of 0.1 mol % to 15 mol %. The total of MgO+ZnO is greater than or equal to 2 mol %. The molar ratio of ZnO/(MgO+ZnO) is in a range of 0.07 to 0.93. The total of Li2O+Na2O is in a range of 6 mol % to 38 mol %. The total of Y2O3+ZrO2+Nb2O5+In2O3+La2O3+Ta2O5 is in a range of 0 mol % to 11 mol %.

Abstract: A mother glass of the present invention for an optical element contains thallium and a boron oxide, serving as an essential component. Therefore, it is possible to manufacture a homogeneous glass body having a low melting temperature and excellent moldability. Further, it is possible to manufacture a distributed index lens having a refractive index distribution required for an optical design, a wide effective visual field, and excellent weather resistance by contacting the glass body with the melted salt of an alkali metal to perform ion exchange. Furthermore, it is possible to provide an optical element and an optical device having excellent optical characteristics by using the distributed index lens.

Abstract: A mother glass composition for graded index lenses, comprising the following glass components in mol %: 40?SiO2?65, 1?TiO2?10, 0?MgO?22, 2?Li2O?18, 2?Na2O?20, 6?Li2O+Na2O?38, and from 0.1 to 15 mol % of any two or more of CaO, SrO and BaO, a graded index lens using the mother glass composition, a manufacturing method of the graded index lens, and an optical product and an optical instrument using the graded index lens, are provided.

Abstract: The present invention is directed to a light-transmitting color film comprising oxides which have high chemical resistance and excellent light-absorption effect, making them available in a wide color range; a method for producing the same; and a coating solution used for forming the color film. In the light-transmitting color film comprising an oxide of an element which serves as a network former and oxides of transition metal elements serving as coloring components, the element serving as a network former is at least one selected from Si, Al, and B, and the transition metal elements comprise Cu, Mn, and Ni; and the two types of oxides form a complex oxide.

Abstract: The present invention is directed to a light-transmitting color film comprising oxides which have high chemical resistance and excellent light-absorption effect, making them available in a wide color range; a method for producing the same; and a coating solution used for forming the color film. In the light-transmitting color film comprising an oxide of an element which serves as a network former and oxides of transition metal elements serving as coloring components, the element serving as a network former is at least one selected from Si, Al, and B, and the transition metal elements comprise Cu, Mn, and Ni; and the two types of oxides form a complex oxide.

Abstract: By using a colored film forming composition, which contains at least an organic silicon compound and chloroauric acid and to which is added at least one type of compound exhibiting the maximum exothermic peak in the range of 170.degree. C. to 250.degree. C., in differential thermal analysis, the precipitation of gold micro-particles on the film surface can be prevented and gold micro-particle dispersion glass can be manufactured in a stable manner.The colored film forming composition of the present invention can thus be used for coating the surface of glass products, especially, windows, mirrors, etc. of automobiles and other vehicles and buildings.

Abstract: Colored film-covered glass articles include a glass substrate and a colored film covering the glass substrate, the colored film containing, by wt %, greater than 50 to 95 of silicon oxide, 0.about.30 of at least one member selected from the group consisting of zirconium oxide, tantalum oxide and titanium oxide, 0.about.25 of cerium oxide, 5.about.20 of gold as coloring fine particles as main components. The glass articles have a visible light reflectance at a side of the glass substrate not covered with the colored film is 10.0% or below. The small visible light reflectance is caused by the surface plasmon absorption of the fine particles of gold.

Abstract: A sunligh absorbing colored film-coated glass article which can freely control color tint, infrared transmittance, UV light transmittance, and visible light transmittance. The colored film-coated glass article which comprises a glass substrate and a colored film formed on one surface thereof, the colored film comprising, in % by weight:5-30% at least one coloring fine particle selected from the group consisting of gold, silver, platinum, palladium, cadmium sulfide, and cadmium selenide;0-50% silicon oxide;0-70% titanium oxide;0-20% cerium oxide; and5-95% at least one coloring metal oxide selected from the group consisting of cobalt oxide, chromium oxide, copper oxide, manganese oxide, nickel oxide, and iron oxide, with the proviso that the total amount of silicon oxide, titanium oxide, and iron oxide is 10 to 95 wt %.

Abstract: UV absorbing, colored film-covered glass articles comprising covering, on a surface of a glass substrate, a UV absorbing, colored film which comprises, as main components expressed by wt %, 5.about.50 of silicon oxide, 5.about.70 of titanium oxide, 20.about.80 of cerium oxide, 5.about.30 of coloring fine particles of at least one member selected from the group consisting of gold, silver, platinum, palladium, cadmium sulfide and cadmium selenide, and 0.about.30 of at least one coloring metal oxide selected from the group consisting of cobalt oxide, chromium oxide, copper oxide, manganese oxide, nickel oxide and iron oxide.The UV absorbing, colored film-covered glass articles can be arbitrarily controlled with respect to the color tone, the UV transmittance, and the visible light transmittance.