Abstract: A glass for chemical strengthening contains, in mole percentage on an oxide basis, 58 to 80% of SiO2, 13 to 18% of Al2O3, 0 to 5% of B2O3, 0.5 to 4% of P2O5, 4 to 10% of Li2O, 5 to 14% of Na2O, 0 to 2% of K2O, 0 to 11% of MgO, 0 to 5% of CaO, 0 to 20% of SrO, 0 to 15% of BaO, 0 to 10% of ZnO, 0 to 1% of TiO2, and 0 to 2% of ZrO2. A value of X is 30000 or more. The value of X is calculated based on the formula, X=SiO2×329+Al2O3×786+B2O3×627+P2O5×(?941)+Li2O×927+Na2O×47.5+K2O×(?371)+MgO×1230+CaO×1154+SrO×733+ZrO2×51.8, by using the contents in mole percentage on an oxide basis of components.

Abstract: A glass for chemical strengthening contains, in mole percentage on an oxide basis, 58 to 72% of SiO2, 7 to 18% of Al2O3, 1% or more of B2O3, 0 to 4% of P2O5, 5 to 16% of Li2O, 0 to 7% of Na2O, 0 to 2% of K2O, 0 to 6% of MgO, 0 to 20% of CaO, 0 to 20% of SrO, 0 to 15% of BaO, 0 to 10% of ZnO, 0 to 1% of TiO2, and 0 to 2% of ZrO2. A value of X is 30000 or more. The value of X is calculated based on the formula, X=SiO2×329+Al2O3×786+B2O3×627+P2O5×(?941)+Li2O×927+Na2O×47.5+K2O×(?371)+MgO×1230+CaO×1154+SrO×733+ZrO2×51.8, by using the contents in mole percentage on an oxide basis of components.

Abstract: The present invention relates to a resin optical waveguide including a core and a cladding having a refractive index lower than that of the core, in which the resin optical waveguide includes, along a light propagation direction, a coupling part at which at least a part of the core is exposed and an optical waveguide part where the whole circumference of the core is covered with the cladding, and the core has a width Wb at an end part of the coupling part at a side of the optical waveguide part being larger than a width Wa of the core at an end part of the coupling part at a side opposite to the optical waveguide part.

Abstract: A glass for chemical strengthening contains, in mole percentage on an oxide basis, 58 to 80% of SiO2, 13 to 18% of Al2O3, 0 to 5% of B2O3, 0.5 to 4% of P2O5, 4 to 10% of Li2O, 5 to 14% of Na2O, 0 to 2% of K2O, 0 to 11% of MgO, 0 to 5% of CaO, 0 to 20% of SrO, 0 to 15% of BaO, 0 to 10% of ZnO, 0 to 1% of TiO2, and 0 to 2% of ZrO2. A value of X is 30000 or more. The value of X is calculated based on the formula, X=SiO2×329+Al2O3×786+B2O3×627+P2O5×(?941)+Li2O×927+Na2O×47.5+K2O×(?371)+MgO×1230+CaO×1154+SrO×733+ZrO2×51.8, by using the contents in mole percentage on an oxide basis of components.

Abstract: Provided is a resin optical waveguide containing a core, under cladding and over cladding, in which the resin optical waveguide has portions having a core width varying along a light propagation direction, the maximum core width is 4 to 10 ?m, and the minimum core width of 1 ?m or more and less than 4 ?m, when the length of a portion S at which the core width is 1 ?m or more and less than 4?m is LS and the length of a portion at which the core width is 4 to 10 ?m is LL, the proportion of LS to the total length is 0.1 to 40%, and the portion S contains neither a certain bubble defect nor a certain defect inside the core and in a vicinity of a core-cladding interface.

Abstract: A resin optical waveguide containing a core, an under cladding and an over cladding having refractive indices lower than that of the core, in which the resin optical waveguide has, at one end side thereof, a core-exposed section at which the over cladding is not present and the core is exposed and, of the under cladding, a portion corresponding to the core-exposed section has a core-neighboring region that satisfies the following (1) and (2): (1) the core-neighboring region is a region whose distance from the core is within x, and x is 5 ?m or more and 20 ?m or less; and (2) the core-neighboring region has a refractive index distribution that the refractive index at a side of an interface with the core is high and the refractive index at a far side from the interface with the core is low.

Abstract: An object is to provide a glass for chemical toughening treatment satisfying low brittleness, low melt viscosity and high chemical toughening characteristics, and a chemically toughened glass using the same. Provided is a glass for chemical toughening treatment containing, in mass % in terms of oxides, SiO2 63 to 76, B2O3 0 to 2, Al2O3 2 to 10, MgO 2 to 12, CaO 0.1 to 8, Na2O 14.5 to 19, K2O 0 to 3, and Fe2O3 0 to 0.5, satisfying a total content of alkali earth metal oxides (RO) being from 5 to 15, satisfying 15×MgO/RO?RO?3, and having a temperature T2 at which a glass viscosity reaches 102 dPa·s being 1,600° C. or lower.

Abstract: The present invention relates to a composite optical waveguide (1) containing a polymer optical waveguide and a silicon optical waveguide adiabatically coupled to each other, in which the polymer optical waveguide and the silicon optical waveguide are coupled to each other by an adhesive layer in an adiabatic-coupling portion where a core of the polymer optical waveguide and a core of the silicon optical waveguide are disposed to face each other, the adhesive layer is formed by using a photocurable adhesive having a glass transition point Tg being 125° C. or higher after curing, and the adiabatic-coupling portion includes a region in which a spacing t between the core of the polymer optical waveguide and the silicon optical waveguide is 1.5 ?m or less.

Abstract: A glass for chemical strengthening contains, in mole percentage on an oxide basis, 58 to 80% of SiO2, 13 to 18% of Al2O3, 0 to 5% of B2O3, 0.5 to 4% of P2O5, 4 to 10% of Li2O, 5 to 14% of Na2O, 0 to 2% of K2O, 0 to 11% of MgO, 0 to 5% of CaO, 0 to 20% of SrO, 0 to 15% of BaO, 0 to 10% of ZnO, 0 to 1% of TiO2, and 0 to 2% of ZrO2. A value of X is 30000 or more. The value of X is calculated based on the formula, X=SiO2×329+Al2O3×786+B2O3×627+P2O5×(?941)+Li2O×927+Na2O×47.5+K2O×(?371)+MgO×1230+CaO×1154+SrO×733+ZrO2×51.8, by using the contents in mole percentage on an oxide basis of components.

Abstract: A glass sheet includes, as represented by mole percentage based on oxides, from 55.5 to 80% of SiO2, from 12 to 20% of Al2O3, from 8 to 25% of Na2O, 2.5% or more of P2O5, and 1% or more of an alkaline earth metal RO (RO is MgO+CaO+SrO+BaO).

Abstract: A glass for chemical strengthening contains, in mole percentage on an oxide basis, 58 to 72% of SiO2, 7 to 18% of Al2O3, 1% or more of B2O3, 0 to 4% of P2O5, 5 to 16% of Li2O, 0 to 7% of Na2O, 0 to 2% of K2O, 0 to 6% of MgO, 0 to 20% of CaO, 0 to 20% of SrO, 0 to 15% of BaO, 0 to 10% of ZnO, 0 to 1% of TiO2, and 0 to 2% of ZrO2. A value of X is 30000 or more. The value of X is calculated based on the formula, X=SiO2×329+Al2O3×786+B2O3×627+P2O5×(?941)+Li2O×927+Na2O×47.5+K2O×(?371)+MgO×1230+CaO×1154+SrO×733+ZrO2×51.8, by using the contents in mole percentage on an oxide basis of components.

Abstract: A glass sheet includes, as represented by mole percentage based on oxides, from 55.5 to 80% of SiO2, from 12 to 20% of Al2O3, from 8 to 25% of Na2O, 2.5% or more of P2O5, and 1% or more of an alkaline earth metal RO (RO is MgO+CaO+SrO+BaO).

Abstract: A glass for chemical strengthening contains, in mole percentage on an oxide basis, 58 to 80% of SiO2, 13 to 18% of Al2O3, 0 to 5% of B2O3, 0.5 to 4% of P2O5, 4 to 10% of Li2O, 5 to 14% of Na2O, 0 to 2% of K2O, 0 to 11% of MgO, 0 to 5% of CaO, 0 to 20% of SrO, 0 to 15% of BaO, 0 to 10% of ZnO, 0 to 1% of TiO2, and 0 to 2% of ZrO2. A value of X is 30000 or more. The value of X is calculated based on the formula, X=SiO2×329+Al2O3×786+B2O3×627+P2O5×(?941)+Li2O×927+Na2O×47.5+K2O×(?371)+MgO×1230+CaO×1154+SrO×733+ZrO2×51.8, by using the contents in mole percentage on an oxide basis of components.

Abstract: A resin optical waveguide containing a core, an under cladding and an over cladding having refractive indices lower than that of the core, in which the resin optical waveguide has, at one end side of, a core-exposed section at which the over cladding is not present and the core and the under cladding nearby the core are exposed and, of the under cladding, a portion corresponding to the core-exposed section has a first layer and a second layer that satisfy a certain condition.

Abstract: A phase-separated glass for chemical strengthening has a total light reflectance of 10% or more in a wavelength range of 380 nm to 780 nm and a value obtained by dividing a maximum value of the total light reflectance by a minimum value of the total light reflectance of 4.2 or less, when measured in a form of a plate having a thickness of 1 mm.

Abstract: A resin optical waveguide containing a core, an under cladding and an over cladding having refractive indices lower than that of the core, in which the resin optical waveguide has, at one end side thereof, a core-exposed section at which the over cladding is not present and the core is exposed and, of the under cladding, a portion corresponding to the core-exposed section has a core-neighboring region that satisfies the following (1) and (2): (1) the core-neighboring region is a region whose distance from the core is within x, and x is 5 ?m or more and 20 ?m or less; and (2) the core-neighboring region has a refractive index distribution that the refractive index at a side of an interface with the core is high and the refractive index at a far side from the interface with the core is low.

Abstract: A white glass includes, in terms of mole percentage on the basis of oxides, from 50% to 74% of SiO2, from 0 to 8% of B2O3, from 1% to 8% of Al2O3, from 0 to 18% of MgO, from 0 to 7% of CaO, from 0 to 10% of SrO, from 0 to 12% of BaO, from 0 to 5% of ZrO2, from 5% to 15% of Na2O and from 2% to 10% of P2O5. In the white glass, a total content of CaO, SrO and BaO is from 1% to 22%, a total content RO of MgO, CaO, SrO and BaO is from 5% to 25% and a ratio CaO/RO of a content of CaO to the RO is 0.7 or less.

Abstract: The present invention relates to a light diffusion plate including a glass plate having a first main surface and a second main surface opposed to the first main surface, in which the glass plate has a thermal expansion coefficient of ?100×10?7/° C. or more and 500×10?7/° C. or less, and light incident on the first main surface is transmitted from the second main surface while being diffused.

Abstract: An object of the present invention is to provide a glass for chemical strengthening which is capable of improving strength as compared with an ordinary soda lime silicate glass even when the same chemical strengthening treatment as that in a conventional process is applied and has good devitrification characteristics, a chemically strengthened glass using the glass for chemical strengthening, and a method for producing the chemically strengthened glass. The present invention provides a glass for chemical strengthening having a specific glass composition described in the present specification.

Abstract: The present invention relates to a method for producing phase-separated glass, sequentially including a melting step of melting a glass, a phase separation step of separating phases in the glass, and a shaping step of shaping the glass, and to the phase-separated glass obtained by the production method.