An X-ray and gamma-ray shielding glass, including the following components in weight-%: 10-35% SiO.sub.2; 60-70% PbO; 0-8% B.sub.2O.sub.3; 0-10% Al.sub.2O.sub.3; 0-10% Na.sub.2O; 0-10% K.sub.2O; 0-0.3% As.sub.2O.sub.3; 0-2% Sb.sub.2O.sub.3; 0-6% BaO; and 0.05-2% ZrO.sub.2.

An X-ray and gamma-ray shielding glass, including the following components in weight-%: 10-35% SiO.sub.2; 60-70% PbO; 0-8% B.sub.2O.sub.3; 0-10% Al.sub.2O.sub.3; 0-10% Na.sub.2O; 0-10% K.sub.2O; 0-0.3% As.sub.2O.sub.3; 0-2% Sb.sub.2O.sub.3; 0-6% BaO; and 0.05-2% ZrO.sub.2.

Certain example embodiments relate to an improved method of strengthening glass substrates (e.g., soda lime silica glass substrates). In certain examples, a glass substrate may be chemically strengthened by creating an electric field within the glass. In certain cases, the chemical tempering may be performed by surrounding the substrate by a plasma including certain ions, such as Li.sup.+, K.sup.+, Mg.sup.2+, and/or the like. In some cases, these ions may be forced into the glass substrate due to the half-cycles of the electric field generated by the electrodes that formed the plasma. This may advantageously chemically strengthen a glass substrate on a substantially reduced time scale. In other example embodiments, an electric field may be set in a float bath such that sodium ions are driven from the molten glass ribbon into the tin bath, which may advantageously result in a stronger glass substrate with reduced sodium content.

A glass polishing apparatus includes a jig that holds a glass structure. The glass polishing apparatus includes a first flat portion, a second flat portion opposite to the first flat portion, and a curved portion connecting the first flat portion to the second flat portion. The jig and includes a first holding surface holding the first flat portion, a second holding surface disposed opposite to the first holding surface and holding the second flat portion, and a third holding surface connecting the first holding surface to the second holding surface and holding the curved portion. At least a portion of a roller unit having a cylindrical shape is inserted between the first flat portion and the second flat portion.

A process includes directing a laser beam at a glass strip so it traverses a line in a drawing direction of the horizontally moving glass strip. A point of incidence of the laser beam is chosen so the line forms an envisaged dividing line between a useful region and a thickened edge region and the point of incidence on the glass is at a position where a temperature of the glass is within a range between an upper viscosity of 10.sup.10 dPas and a lower viscosity of 10.sup.15 dPas. The laser beam photothermally processes the glass strip so a gap is formed along the line between the useful region and the thickened edge region to obtain a glass strip with a homogeneous glass thickness and a new edge parallel to the drawing direction and a separated thickened edge region. The glass strip with homogeneous thickness is cooled after separation.

A process includes directing a laser beam at a glass strip so it traverses a line in a drawing direction of the horizontally moving glass strip. A point of incidence of the laser beam is chosen so the line forms an envisaged dividing line between a useful region and a thickened edge region and the point of incidence on the glass is at a position where a temperature of the glass is within a range between an upper viscosity of 10.sup.10 dPas and a lower viscosity of 10.sup.15 dPas. The laser beam photothermally processes the glass strip so a gap is formed along the line between the useful region and the thickened edge region to obtain a glass strip with a homogeneous glass thickness and a new edge parallel to the drawing direction and a separated thickened edge region. The glass strip with homogeneous thickness is cooled after separation.