A glass sheet thermally strengthened such that at the first major surface is under compressive stress; the sheet having an a characteristic 2D autocorrelation matrix c(x,y) given by c(x,y)=F.sup.1(F(g).Math.F(g)) where F is a 2D Fourier transform and represents a complex conjugate operation and g is a high pass filtered data array given by g(x,y)=F.sup.1(F(f(1F(h)) where h is a spatial 2D low pass filter array and f is a square data array of Shear 0 and Shear 45 data, taken over an area away from any birefringence edge effects on the sheet, wherein an autocorrelation peak maximum width of the matrix c(x,y) at 40% of peak height, for the c(x,y) matrices from both the Shear 0 and Shear 45 data, is between 1 and 5 mm.

A strengthened glass or glass ceramic sheet has a roughness of greater than 0.05 nm Ra and less than 0.08 nm Ra over an area of 10 m10 m and has the property that, excluding areas within three sheet thicknesses of the outer edge surface of the sheet, the slope of a measured value of a thermally affected property of glass over distance along the first major surface of the sheet is higher bordering one or more lower-cooling-rate-effect-exhibiting areas on the first surface of the sheet than elsewhere on the first surface of the sheet, and at least one of said one or more areas has a shortest linear dimension, in a direction parallel to the first major surface, of less than 100000 m.

A glass article having a low level of grainy appearance that can appear to have a shift in the pattern of the grains with changing viewing angle of a display, or sparkle. The glass articlewhich, in some embodiments, is a transparent glass sheethas small-angle-scattering properties and/or distinctness-of-reflected-image (DOI), leading to improved viewability in display applications, especially under high ambient lighting conditions. In some embodiments, the antiglare surface of the glass sheet is an etched surface, with no foreign coating present on the antiglare surface.

A method of treating a surface of a silicon substrate forms an accelerated gas cluster ion beam of carbon atoms, promotes fragmentation and/or dissociation of gas cluster ions in the beam, removes charged particles from the beam to form a neutral beam, and treats a portion of a surface of the silicon substrate by irradiating it with the neutral beam. A silicon substrate surface layer of SiC.sub.X (0.05<X<3) formed by accelerated and focused Neutral Beam irradiation of a silicon substrate wherein the Neutral Beam is derived from a gas cluster ion beam which has had its cluster ions dissociated and charged particles removed.

Provided is a solar cell module which has a high anti-glare property and is capable of maintaining power output at a high level. In a solar cell module with a light-incident surface formed by laminating an antireflection film on a plate body made of glass, and a surface of the plate body is roughened. A substance for forming the antireflection film is introduced into a space formed in a crack situated slightly inside from the roughened surface. Formation of a layer of air in the crack is prevented to suppress reflection of light at a portion in which the crack is formed.

The invention relates to a glass sheet, in particular a glass sheet obtained by separation from a preferably floated glass ribbon formed by hot forming, in particular comprising a borosilicate glass, with a length of at least 1.15 m and a width of at least 0.85 m, with a thickness d of at least 0.5 mm, preferably at least 0.7 mm, and at most 7 mm, and uses thereof.

Embodiments of a deadfront article are provided. The deadfront article includes a substrate having a first surface and a second surface. The deadfront article also includes a semi-transparent layer disposed onto the second surface of the substrate. The semi-transparent layer has a region of a solid color or of a design of two or more colors, and the semi-transparent layer has a first optical density. Further, the deadfront article includes a contrast layer disposed onto the region. The contrast layer is configured to enhance visibility of the color(s) of the semi-transparent layer.

An object of the present invention is to obtain a reflective mask blank capable of obtaining high contrast at the edges of a phase shift film pattern. Provided is a reflective mask blank comprising a multilayer reflective film and a phase shift film that shifts the phase of EUV light formed in that order on a substrate, wherein root mean square roughness (Rms), obtained by measuring a 1 m1 m region on the surface of the phase shift film with an atomic force microscope, is not more than 0.50 nm, and power spectrum density at a spatial frequency of 10 to 100 m.sup.1 is not more than 17 nm.sup.4.

A large-size synthetic quartz glass substrate has a diagonal length of at least 1,000 mm. Provided that an effective range is defined on the substrate surface, and the effective range is partitioned into a plurality of evaluation regions such that the evaluation regions partly overlap each other, a flatness in each evaluation region is up to 3 m. From the quartz glass substrate having a high flatness and a minimal local gradient within the substrate surface, a large-size photomask is prepared.

A method of the present invention for producing glass sheets includes the steps of: (I) forming a molten glass raw material into a glass ribbon on a molten metal; and (II) bringing an acid gas that contains a fluorine element (F)-containing acid and in which a volume ratio of water vapor to the acid (a volume of the water vapor/a volume of the acid) is 0 or more and 30 or less, into contact with a surface of the glass ribbon on the molten metal so as to subject the surface of the glass ribbon to dealkalization and control a morphology of the surface in accordance with the volume ratio.