Abstract: The present invention pertains to glass containing, in terms of mass % on an oxide basis, 40-80% of SiO2, 1-30% of Al2O3, and 1-40% of CaO, the glass having dmisteinbergite as the crystalline phase. Such glass makes it difficult for cracks to progress and has exceptional crack resistance.

Abstract: The present invention pertains to glass containing, in terms of mass % on an oxide basis, 40-80% of SiO2, 1-30% of Al2O3, and 1-40% of CaO, the glass having dmisteinbergite as the crystalline phase. Such glass makes it difficult for cracks to progress and has exceptional crack resistance.

Abstract: Provided is a light-emitting glass which is applicable to, e.g., white illuminators including a light-emitting diode as a light source, and which emits light of a warm white color when irradiated with near ultraviolet light and combines long-term weatherability with high heat resistance; a light-emitting device containing same and a process for producing same. The light-emitting glass includes, as the base glass, borosilicate or silicate glass having a separated-phase structure, whereby the base glass is efficiently doped with, for example, transition metal ion clusters which emit light of a warm white color upon irradiation with near ultraviolet light. With this glass, it is possible to attain increases in excitation wavelength and emission wavelength. The glass thus emits, based on a multiple scattering effect, high-intensity light of a warm white color upon irradiation with near ultraviolet light.

Abstract: Provided is a light-emitting glass which is applicable to, e.g., white illuminators including a light-emitting diode as a light source, and which emits light of a warm white color when irradiated with near ultraviolet light and combines long-term weatherability with high heat resistance. Also provided are a light-emitting device equipped with the light-emitting glass and a process for producing the light-emitting glass. The light-emitting glass includes, as the base glass, borosilicate or silicate glass having a separated-phase structure, whereby the base glass is efficiently doped with, for example, transition metal ion clusters which emit light of a warm white color upon irradiation with near ultraviolet light. With this glass, it is possible to attain increases in excitation wavelength and emission wavelength. The glass thus emits, based on a multiple scattering effect, high-intensity light of a warm white color upon irradiation with near ultraviolet light.

Abstract: A method of manufacturing a large-diameter gradient-index glass having a predetermined refractive index gradient includes the steps of (a) hydrolyzing a solution consisting of an alkoxide of silicon and an alkoxide of boron to prepare a sol, (b) adding an aqueous solution of lead acetate and an organic acid to the sol to prepare a gel porous body, (c) aging and sequentially treating the gel porous body by using a water-isopropanol solution of lead acetate, an isopropanol-acetone solution, and acentone, thereby performing a pretreatment, (d) dipping the pretreated gel porous body into a lower alcohol solution of at least one of potassium acetate and sodium acetate to form a lead ion concentration distribution which is gradually changed from a surface to an interior of the gel porous body, (e) sequentially treating the gel porous body having the lead ion concentration distribution by sequentially using an isopropanol-acetone solution and acentone, and (f) drying and heating the gel porous body to prepare a glas