Described is in particular a method of heat treatment of a material layer (102) of a material sandwich (100) comprising the material layer (102) and a substrate (104), wherein the substrate (104) comprises a silicon-oxygen compound and the material layer (102) comprises a silicon-oxygen compound, the method comprising irradiating the material layer (102) with a pulsed laser beam (114) of a carbon dioxide laser (112). According to an embodiment the irradiating is performed so as to selectively heat the material layer (102) and a substrate portion (116) of the substrate (104), wherein the substrate portion (116) faces (e.g. contacts) the material layer (102).

A transparent, colorless and non-scattering glass-ceramic plate of lithium aluminosilicate type and containing crystals of β-quartz structure, the chemical composition of which does not contain oxides of arsenic, of antimony and of neodymium, and includes the following constituents within the limits defined below, expressed as weight percentages: SiO.sub.2 55-75%; Al.sub.2O.sub.3 12-25%; Li.sub.2O 2-5%; Na.sub.2O+K.sub.2O 0-<2%; Li.sub.2O+Na.sub.2O+K.sub.2O 0-<7%; CaO 0.3-5%; MgO 0-5%; SrO 0-5%; BaO 0.5-10%; CaO+BaO >1%; ZnO 0-5%; TiO.sub.2 ≦1.9%; ZrO.sub.2 ≦3%;TiO.sub.2+ZrO.sub.2 >3.80%; SnO.sub.2 ≧0.1%; SnO.sub.2/(SnO.sub.2+ZrO.sub.2+TiO.sub.2)<0.1.

Information is stored in an optical element in the form of a glass or plastic body embodied as spectacles lens, spectacles lens blank or spectacles lens semi-finished product. The information in the form of data is stored on or in the glass or plastic body by creating at least one marking with a marking system. The marking can be read by a reading apparatus. The marking system has an interface for reading information individualizing the optical element. The marking is created permanently by the marking system on or in the optical element at a definition point of a local body-specific coordinate system set by two points on or in the optical element. In this body coordinate system, the manufacturer specifies the position of the lens horizontal and/or the far and/or the near and/or the prism reference point.

A glass tube semi-finished product or a hollow glass product manufactured from the glass tube semi-finished product is provided with a first marking with information on the origin and/or tube-specific production data of the glass tube semi-finished product, which marking is read from the hollow glass product after its manufacture to determine the origin and/or the tube-specific production data of the glass tube semi-finished product, e.g., to identify the semi-finished glass tube from which the hollow glass product has been made, and/or trace the tube-specific production data of this glass tube semi-finished product. This means that the entire supply chain for the hollow glass product from the supplier of the originally used glass tube semi-finished product up to the end product can be determined. The physical and chemical characteristics of the glass tube semi-finished product are not altered for producing the first marking.

A method for preparation of a self-cleaning coating solution is provided. The method comprises mixing an aluminium compound with a solution of an ethanol compound to form a solution. Further, the formed solution is subjected to a first magnetic stirring. After the first magnetic stirring a first transparent solution is formed. Further, a stabilizing agent is added to the first transparent solution of the aluminium compound and the ethanol compound. Subsequent to adding the stabilizing agent a translucent solution is formed. Finally, the formed translucent solution is subjected to a second magnetic stirring for forming a homogeneous second transparent solution. The formed second transparent solution is a coating solution

A quantum dot (“QD”) glass aging device including a bottom part including a flat surface defined by a first direction and a second direction intersecting the first direction; a side wall part including a side surface defined by the first direction and a third direction intersecting the bottom part, and a seating part disposed between the bottom part and the side wall part. The seating part includes a plurality of protrusion parts extending in the first direction and arranged in the second direction. A plurality of QD glasses is arranged on the plurality of protrusion parts. A plurality of light sources is disposed in the plurality of grooves defined between the protrusion parts and between the side wall part and a first protrusion part adjacent to the side wall part. Heights of upper surfaces of the protrusion parts gradually decrease from the side wall part to the bottom part.

When a laser beam is used to perform shape processing on an edge surface of a disk-shaped glass plate, in order to suppress strain (retardation values) in the main surface of the glass plate, the disk-shaped glass plate is floated above a base, and the edge surface of the glass plate is processed into a target shape by irradiating the edge surface with the laser beam while contactlessly heating the glass plate in a state where the glass plate is floated, and moving the laser beam relative to the edge surface in the circumferential direction of the disk-shaped glass plate.

A method for selective laser-induced etching of a microhole into a workpiece includes creating a modification in the workpiece that extends from an entrance side to an exit side of the workpiece. The modification is created by a laser pulse that has an annular transverse intensity distribution. The modification delimites a cylindrical body from a residual material surrounding the modification. The method further includes introducing the workpiece with the modification into a wet-chemical etching bath for structurally separating the cylindrical body from the residual material.

Embodiments of a glass substrate including an alkali-containing bulk and an alkali-depleted surface layer, including a substantially homogenous composition with at least 51 mol % Al.sub.2O.sub.3 are disclosed. In some embodiments, the alkali-depleted surface layer includes about 0.5 atomic % alkali or less. The alkali-depleted surface layer can be substantially free of hydrogen and/or crystallites. Methods for forming a glass substrate with a modified surface layer are also provided.

A glass glass-ceramic composite comprises a substrate comprising an alkali-containing glass bulk, the bulk comprising Al.sub.2O.sub.3 and SiO.sub.2 and alkali, and a glass-ceramic surface layer, the surface layer comprising an alkali-depleted glass ceramic comprising Al.sub.2O.sub.3 and SiO.sub.2 with at least 5% crystalline phase by volume, wherein the alkali-depleted glass ceramic surface layer comprises a mol % Al.sub.2O.sub.3 of at least 51%. A method of preparing the composite is also disclosed.