Provided is a glass production method that can suppress devitrification of glass and increase the productivity of the glass. A glass production method according to the present invention includes the steps of: pouring a melt 11 obtained by melting a raw material of a glass 18 into a mold 13; and cooling the melt 11 to obtain the glass 18, wherein the mold 13 has a bottom surface 14a and a side surface 15a and, in the step of cooling the melt 11, the mold 13 is cooled from a direction of the bottom surface 14a.

A white glass container derived from a phase separation phenomenon of a halogen-free glass composition includes a neck portion and a body portion. The glass composition includes as ingredients at least SiO.sub.2, P.sub.2O.sub.5, Al.sub.2O.sub.3, B.sub.2O.sub.3, R.sub.2O (R=Na or K), MgO, CaO and the like. The neck portion and the body portion respectively have a white multilayer structure formed to successively include a white transparent layer of relatively low white coloration and a white opaque layer of relatively high white coloration from the outer surface side. The contents of P.sub.2O.sub.5 in the white transparent layer are made smaller than the contents of P.sub.2O.sub.5 in the white opaque layer.

A method for manufacturing an optical element includes heating an optical material up to a first temperature that is higher than a transition point, pressurizing the optical material using a first mold and a second mold that are situated opposite to each other across the optical material, first cooling the optical material down to a second temperature that is higher than a strain point and lower than the first temperature while pressurizing the optical material with a predetermined load using the first mold and the second mold, releasing the predetermined load at a set speed that is higher than or equal to a speed obtained in advance, at which an elastic deformation occurs preferentially over a viscous deformation in the optical material upon releasing a load, and second cooling the optical material down to a third temperature that is lower than the second temperature.

A method for manufacturing an optical element includes pressing a phosphate-based glass containing Bi.sub.2O.sub.3 in a proportion of 10 mass % or higher and 30 mass % or lower with a hot mold; and then cooling the same, in which pressure equal to or higher than the critical pressure of oxygen and equal to or lower than a strength of glass is continuously applied to the glass from the time of bringing the glass into contact with the pressing surface of the mold at a glass viscosity of log =9 [dPa.Math.sec] or higher and 10 [dPa.Math.sec] or lower until the glass viscosity log increases to 12 [dPa.Math.sec] by cooling.

There are provided a glass container that includes mouth portions formed at both end portions thereof facing each other and a manufacturing method of the glass container. Since the glass container is integrally molded by a one-press manufacturing method, the glass container may be more easily manufactured and the mechanical strength of the glass container may be improved in comparison with a case in which portions including mouth portions are separately manufactured and then are integrated with each other. Further, since the glass container is obtained by a one-press manufacturing method, the glass container is thick and has a high-class feeling. A glass container, which is integrally molded by a one-press manufacturing method, includes a first mouth portion and a second mouth portion that are formed at both end portions of the glass container facing each other.

An optical element manufacturing device includes a mold set including: a first shaping mold and a second shaping mold facing each other with a shaping-target material between the first and second shaping molds, and a sleeve located around the first and second shaping molds; and a plurality of stages on which the mold set is conveyed and which heat, press or cool the shaping-target material. The sleeve is conveyed to the stages in such a manner that a conveyance-direction front side of the mold set in an arrangement direction of the plurality of stages has a heat insulation portion with a heat insulation property that is higher than that on a conveyance-direction rear side of the mold set in order to reduce a temperature distribution in the shaping-target material.

A method for texturing a substrate includes 3-D printing a pattern onto a substrate to form a texture. The pattern has a root mean square roughness between 40 to 1000 microns and an autocorrelation function greater than 0.5 for distances less than 50 microns.