The invention relates to a method for forming a glass item, in particular a three-dimensionally formed flat glass item, wherein the following steps are carried out: arranging a flat formation of glass, for example a flat glass pane of homogeneous thickness or a flat glass pane of inhomogeneous thickness or a preformed flat glass pane blank or liquid two-dimensionally spread glass, between a mould plunger and a melt of liquid metal, in particular tin; tempering of at least one part to be formed of the flat formation of glass to a forming temperature of the glass at which the glass has a viscosity in the range from 10 Pas to 106.5 Pas, preferably in the range from 10 Pas to 104 Pas and particularly preferably in the range from 10 Pas to 103 Pas; forming the flat formation of glass by moving the mould plunger and a surface of the molten metal towards each other, preferably by means of at least one linear movement, for example by means of a linear motor or servomotor, so that the flat formation of glass is pressurised either by the mould plunger on the one hand and by the molten metal on the other hand and is formed by the pressurisation on both sides and/or by suctioning and conforming the flat formation of glass onto the mould plunger; cooling the formed flat formation of glass to a handling temperature below the forming temperature at which the glass has a viscosity of ?107 Pas; and demoulding the cooled flat formation; as well as a device for carrying out the method and a use of a molten metal for carrying out the method.

The invention relates to a method for forming a glass item, in particular a three-dimensionally formed flat glass item, wherein the following steps are carried out: arranging a flat formation of glass, for example a flat glass pane of homogeneous thickness or a flat glass pane of inhomogeneous thickness or a preformed flat glass pane blank or liquid two-dimensionally spread glass, between a mould plunger and a melt of liquid metal, in particular tin; tempering of at least one part to be formed of the flat formation of glass to a forming temperature of the glass at which the glass has a viscosity in the range from 10 Pas to 106.5 Pas, preferably in the range from 10 Pas to 104 Pas and particularly preferably in the range from 10 Pas to 103 Pas; forming the flat formation of glass by moving the mould plunger and a surface of the molten metal towards each other, preferably by means of at least one linear movement, for example by means of a linear motor or servomotor, so that the flat formation of glass is pressurised either by the mould plunger on the one hand and by the molten metal on the other hand and is formed by the pressurisation on both sides and/or by suctioning and conforming the flat formation of glass onto the mould plunger; cooling the formed flat formation of glass to a handling temperature below the forming temperature at which the glass has a viscosity of ?107 Pas; and demoulding the cooled flat formation; as well as a device for carrying out the method and a use of a molten metal for carrying out the method.

The invention relates to a solar concentrator comprising a solid body consisting of a transparent material that has a light coupling surface and a light decoupling surface, the solid body having a light guide part that tapers towards the light decoupling surface, being located between the light coupling surface and the light decoupling surface and being delimited by a light guide surface between the light coupling surface and the light decoupling surface, the light guide surface merging into the light decoupling surface with a constant first derivation. The invention also relates to a method for the production of a solar concentrator, wherein the transparent material is precision-molded between the molds.

The invention relates to a solar concentrator comprising a solid body consisting of a transparent material that has a light coupling surface and a light decoupling surface, the solid body having a light guide part that tapers towards the light decoupling surface, being located between the light coupling surface and the light decoupling surface and being delimited by a light guide surface between the light coupling surface and the light decoupling surface, the light guide surface merging into the light decoupling surface with a constant first derivation. The invention also relates to a method for the production of a solar concentrator, wherein the transparent material is precision-molded between the molds.

A mold which is made of a porous heat-resistant material comprises a first surface and a second surface opposite to the first surface. A plurality of light guide spots are formed on the first surface. The light guide spots are light guide spots. The first surface is a smooth polished surface, the mold enables direct manufacture of light guide plates for less heat expended.