To provide a glass plate for a window material and a window comprising the glass plate, which are less likely to be a barrier to radio transmitting/receiving in use of a radio-utilizing apparatus, and a radio communication apparatus comprising the glass plate. A glass plate having a radio transmittance of at least 20% at a frequency of 100 GHz as calculated as 18 mm thickness, a window comprising the glass plate, and a radio communication apparatus comprising the glass plate.

To provide a glass plate for a window material and a window comprising the glass plate, which are less likely to be a barrier to radio transmitting/receiving in use of a radio-utilizing apparatus, and a radio communication apparatus comprising the glass plate. A glass plate having a radio transmittance of at least 20% at a frequency of 100 GHz as calculated as 18 mm thickness, a window comprising the glass plate, and a radio communication apparatus comprising the glass plate.

The present invention relates to a chemically strengthened glass having a thickness of t [mm], and having a profile of a stress value CS.sub.x [MPa,] at a depth x [.Math.m] from a surface of the glass, the stress value being measured by a scattered-light photoelastic stress meter, in which a second-order differential value CS.sub.x" of the stress value CS.sub.x in the profile satisfies the following expression within a range of CS.sub.x≥0: 0<CS.sub.x"≤0.050.

The present invention relates to a chemically strengthened glass having a thickness of t [mm], and having a profile of a stress value CS.sub.x [MPa,] at a depth x [.Math.m] from a surface of the glass, the stress value being measured by a scattered-light photoelastic stress meter, in which a second-order differential value CS.sub.x" of the stress value CS.sub.x in the profile satisfies the following expression within a range of CS.sub.x≥0: 0<CS.sub.x"≤0.050.

An article including a glass having that includes SiO.sub.2, Al.sub.2O.sub.3, and B.sub.2O.sub.3 and least one of Li.sub.2O, Na.sub.2O, K.sub.2O, MgO, CaO, SrO, BaO, SnO.sub.2, ZnO, La.sub.2O.sub.3, F, and Fe.sub.2O.sub.3, wherein the glass includes a dielectric constant of about 10 or less and/or a loss tangent of about 0.01 or less, both as measured with signals at 10 GHz.

Provided is a wavelength conversion member that is less decreased in luminescence intensity with time by irradiation with light of an LED or LD and a light emitting device using the wavelength conversion member. A wavelength conversion member is formed of an inorganic phosphor dispersed in a glass matrix, wherein the glass matrix contains, in % by mole, 30 to 85% SiO.sub.2, 0 to 20% B.sub.2O.sub.3, 0 to 25% Al.sub.2O.sub.3, 0 to 3% Li.sub.2O, 0 to 3% Na.sub.2O, 0 to 3% K.sub.2O, 0 to 3% Li.sub.2O+Na.sub.2O+K.sub.2O, 0 to 35% MgO, 0 to 35% CaO, 0 to 35% SrO, 0 to 35% BaO, 0.1 to 45% MgO+CaO+SrO+BaO, and 0 to 4% ZnO, and the inorganic phosphor is at least one selected from the group consisting of an oxide phosphor, a nitride phosphor, an oxynitride phosphor, a chloride phosphor, an oxychloride phosphor, a halide phosphor, an aluminate phosphor, and a halophosphate phosphor.

Provided is a wavelength conversion member that is less decreased in luminescence intensity with time by irradiation with light of an LED or LD and a light emitting device using the wavelength conversion member. A wavelength conversion member is formed of an inorganic phosphor dispersed in a glass matrix, wherein the glass matrix contains, in % by mole, 30 to 85% SiO.sub.2, 0 to 20% B.sub.2O.sub.3, 0 to 25% Al.sub.2O.sub.3, 0 to 3% Li.sub.2O, 0 to 3% Na.sub.2O, 0 to 3% K.sub.2O, 0 to 3% Li.sub.2O+Na.sub.2O+K.sub.2O, 0 to 35% MgO, 0 to 35% CaO, 0 to 35% SrO, 0 to 35% BaO, 0.1 to 45% MgO+CaO+SrO+BaO, and 0 to 4% ZnO, and the inorganic phosphor is at least one selected from the group consisting of an oxide phosphor, a nitride phosphor, an oxynitride phosphor, a chloride phosphor, an oxychloride phosphor, a halide phosphor, an aluminate phosphor, and a halophosphate phosphor.

Provided is a Li.sub.2O-Al.sub.2O.sub.3-SiO.sub.2-based crystallized glass that has a high permeability to light in a ultraviolet to infrared range and is less likely to be broken. A Li.sub.2O-Al.sub.2O.sub.3-SiO.sub.2-based crystallized glass contains, in terms of % by mass, 40 to 90% Si.sub.O2, 5 to 30% Al.sub.2O.sub.3, 1 to 10% Li.sub.2O, 0 to 20% SnO.sub.2, 0 to 5% ZrO.sub.2, 0 to 10% MgO, 0 to 10% P.sub.2O.sub.5, and 0 to 4% TiO.sub.2 and a mass ratio of Li.sub.2O/(MgO+CaO+SrO+BaO+Na.sub.2O+K.sub.2O) is 3 or less.

An optical diffuser can comprise an amorphous phase and a crystalline phase comprising lithium disilicate and one or more of ß-spodumene or ß-quartz comprising a median grain size ranging from about 500 nanometers to about 1,000 nanometers. The crystalline phase can be dispersed throughout a volume of the optical diffuser. The optical diffuser can comprise, on an oxide basis in mol %, SiO.sub.2: 60-75; Al.sub.2O.sub.3: 2-9; Li.sub.2O: 17-25; and Na.sub.2O+K.sub.2O: 0.5-6. Methods of making an optical diffuser can comprise forming a mixture by melting together, on an oxide basis in mol %, SiO.sub.2: 60-75; Al.sub.2O.sub.3: 2-9; Li.sub.2O: 17-25; and Na.sub.2O+K.sub.2O: 0.5-6. Methods can comprise forming a ribbon from the mixture. Methods can comprise heating the ribbon about 850° C. to about 900° C. for about 0.5 hours to about 6 hours.

The present invention relates to a chemically strengthened glass ceramic including a crystalline phase, having two main surfaces opposed to each other, and including an amorphized region in a surface layer of at least one of the main surfaces and a crystallized region inside the glass, in which the amorphized region has a crystallinity of 10 vol % or less at a depth of 100 nm from an outermost surface of the glass.