The present invention provides a glass sheet having a good property of blocking transmission of ultraviolet light, having a low to moderate visible transmittance, being relatively thin, being capable of substantially blocking transmission of solar ultraviolet light, and also having a good solar shielding property. The glass sheet of the present invention has a thickness of 1 to 5 mm, a Tuv 380 of 1.5% or less, a Tuv 400 of 2.5% or less, a visible transmittance (YA) of 5 to 40%, and a solar transmittance (TG) of 5 to 45%, and is formed from a glass composition, wherein the glass composition includes: 1.0 to 5.0 wt % T-Fe.sub.2O.sub.3; 1.0 to 5.0 wt % TiO.sub.2; and 50 to 600 wt. ppm CoO as coloring components in addition to predetermined base composition, a FeO ratio is 5 to 40%, and the sum of T-Fe.sub.2O.sub.3 multiplied by 2 and TiO.sub.2 is 7.0% or more.

An optical member includes a transparent substrate containing at least one substance selected from glass, a glass ceramic, silicon, and sapphire, and having an infrared high-transmittance region in which an optical transmittance is 78% or more in a wavelength band of 700 nm to 1800 nm; and an optical interference film disposed on a main surface of the transparent substrate corresponding to the infrared high-transmittance region, wherein a transmittance of light, of the optical member, of at least one wavelength λ.sub.3 in the wavelength band of 700 nm to 1800 nm in a region of the optical member corresponding to the infrared high-transmittance region of the transparent substrate has a minimum value of 86.5% or more and has a difference between the minimum value and a maximum value of 9% or less in a range where an incidence angle is from 0 degrees to 60 degrees.

A pre-stressed structure and a method for forming a pre-stressed structure are provided. The pre-stressed structure comprises a panel including a first region pre-stressed into a condition of membrane tension, resulting in the panel having increased transverse stiffness. The pre-stressed structure may further comprise a second region pre-stressed into a condition of membrane compression. The panel may be a plate or a shell and may form part of an insulating glass unit, which in turn may form part of a curtainwall unit.

A process for manufacturing a heat strengthened glass, includes a heat treatment applied to a thermally tempered glass. Moreover, a heat strengthened glass sheet in accordance with standard EN1863-1:2011 has a surface stress of greater than 30 MPa, an edge compressive stress of greater than 30 MPa, a mean optical retardation of less than 40 nm.

The invention provides a glass surface stress meter and multiple-tempered glass surface stress meter, and the glass surface stress meter includes a light source (810, 910), a light refraction element (820, 920) and an imaging unit. The light refraction element (820, 920) is provided at a light-emitting direction of the light source (810, 910) for placing a measured glass (970). The light from the light source (810, 910) comes into the imaging unit to imaging after refracted by the light refractive element (820, 920). The imaging unit includes lens group (830, 940) and a imaging sensor (840, 960). A front end of the lens group is provided at the light-refraction direction of the light refraction element (820, 920) and a back-end is provided with the imaging sensor.

A process for manufacturing a bent laminated glazing, includes manufacturing a first bent laminated glazing including at least two glass substrates locally comprising, in each of the at least two glass substrates and facing each other in all the at least two glass substrates, a zone including compressive stresses, and cutting the first bent laminated glazing through its entire thickness along a line included in the zone in order to form local cut edges and, after cutting, a second bent laminated glazing with the local cut edges having compressive edge stresses.

A strengthened glass article has opposing first and second compressively stressed surface portions bound to a tensilely stressed core portion, with the first surface portion having a higher level of compressive surface stress than the second surface portion for improved resistance to surface damage, the compressively stressed surface portions being provided by lamination, ion-exchange, thermal tempering, or combinations thereof to control the stress profiles and limit the fracture energies of the articles.

A laminated includes two bent glass substrates, a polymer interlayer between the glass substrates, and a notch or orifice cut in an entire thickness of the glazing. The glazing includes a border of compressive edge stresses obtained by general controlled cooling of the substrates in a paired state so that compressive stresses are generated at the border, and a local compression zone, different from the border, and obtained by local controlled cooling of a local area of a main surface of the glazing so that compressive stresses are generated in theid local compression zone. The notch or orifice is located in the local compression zone and made in the substrates in a paired state after forming the local compression zone so that cut contours of the substrates in the notch or orifice have a perfect superposition. The compressive edge stresses of the cut contours are greater than 4 MPa.

A device and a process for manufacturing a bent individual glass sheet including a peripheral compression belt, wherein the process includes the heating thereof to its bending temperature in a furnace, the individual bending thereof, and the general cooling thereof. One zone of the sheet at least partially inside the peripheral compression belt, referred to as locally cooled zone, undergoes, after the heating of the sheet, a local cooling faster than the general cooling, when the sheet is at a temperature of at least 530 C. The cutting of the sheet on the locally cooled zone creates edges having edge compressive stresses.

To provide a method for tempering glass to obtain tempered glass having high surface quality and a deep compression stress layer. The present invention relates to a method for tempering a glass plate comprising a preparation step of preparing a glass plate having a surface temperature of at most the strain point, an internal heating step of heating the internal temperature of the glass plate to be at least the annealing point, while maintaining the surface temperature of the glass plate within 10 minutes, or to be at most the strain point, and a cooling step of cooling the glass plate.