Abstract: The invention relates to a method for severing brittle flat materials, for example made of glass, ceramic, silicon, gallium arsenide or sapphire. The method includes the step of heating the flat material along desired dividing lines below its melting temperature by means of a laser alone desired separating lines. Then the material is shocked by a coolant jet so that a thermally-induced mechanical stress difference brings about a material separation. Traces are formed in the flat material in advance along the separation lines, so that the flat material has a lower breaking stress along the traces than in the unworked flat material, and the separation with the laser takes place along these traces.

Abstract: The present invention relates to a method of dividing a plane-parallel plate made of a brittle material into a plurality of individual plates having a specified edge length, in which break-off cuts are made along specified scored lines that form a lattice-like pattern by introducing thermally induced stresses by means of a laser beam, and in which, after making the break-off cuts along a first working direction, the resultant plate strips are spaced out at intervals in that a framed stretch film to which the plane-parallel plate is bonded is stretched by means of a vacuum device. The invention also relates to a device with a special clamping table for use in carrying out the method.

Abstract: The invention is directed to a method in which disks, particularly wafers, of brittle material are severed along planned severing lines by a laser by introducing thermal stresses. The temperature gradient required for this and the compressive stresses and tensile stresses resulting from it are generated in that the disk is first cooled proceeding from its underside at least along the planned severing lines toward the upper side of the disk, and the upper side of the disk is then acted upon by a laser beam along the planned severing lines. The description also relates to an apparatus for carrying out the method.

Abstract: The invention relates to a method and to a device for the mechanical structuring of thin-film solar cells which are carried on a flexible carrier layer in the form of a material web. The material web is held on a support, where the groove areas, into which grooves are introduced for structuring with a mechanical scoring tool, are pulled onto elastic bases, by holding the material web by frictional engagement over adjacent groove-free areas.

Abstract: The present invention relates to a method of dividing a plane-parallel plate made of a brittle material into a plurality of individual plates having a specified edge length, in which break-off cuts are made along specified scored lines that form a lattice-like pattern by introducing thermally induced stresses by means of a laser beam, and in which, after making the break-off cuts along a first working direction, the resultant plate strips are spaced out at intervals in that a framed stretch film to which the plane-parallel plate is bonded is stretched by means of a vacuum device. The invention also relates to a device with a special clamping table for use in carrying out the method.

Abstract: The invention relates to a method for severing brittle flat materials, for example made of glass, ceramic, silicon, gallium arsenide or sapphire. The method includes the step of heating the flat material along desired dividing lines below its melting temperature by means of a laser along desired separating lines. Then the material is shocked by a coolant jet so that a thermally-induced mechanical stress difference brings about a material separation. Traces are formed in the flat material in advance along the separation lines, so that the flat material has a lower breaking stress along the traces than in the unworked flat material, and the separation with the laser takes place along these traces.

Abstract: A method and apparatus for trimming the edges of a float glass ribbon whose thickness can vary between 0.4 mm and 24 mm in which a specific depth crack is generated for the respective thickness. The depth of the crack is actively influenced by energy introduced by means of a laser which is controlled as a function of the surface temperature of the float glass ribbon and by a subsequent cooling whose acting period is variable. To ensure a permanently reliable process, the severing crack and the thickness of the float glass ribbon are detected in order to initiate a new initial crack immediately in the event that the severing crack should break up and so that a cutting unit comprising the scribing device, the beam-shaping optics and the cooling nozzles is always at a constant vertical distance from the surface of the float glass ribbon. The method and apparatus are distinguished particularly by the fact that only a low laser power is required.

Abstract: The invention is directed to a method in which disks, particularly wafers, of brittle material are severed along planned severing lines by a laser by introducing thermal stresses. The temperature gradient required for this and the compressive stresses and tensile stresses resulting from it are generated in that the disk is first cooled proceeding from its underside at least along the planned severing lines toward the upper side of the disk, and the upper side of the disk is then acted upon by a laser beam along the planned severing lines. The description also relates to an apparatus for carrying out the method.

Abstract: In accordance with the method of the invention, flat workpieces of brittle material, e.g., sapphire, glass ceramic, or glass, can be severed by inducing thermomechanical stresses, particularly along severing lines of the same direction, with a laser beam having a beam spot with asymmetric radiation density distribution on the workpiece by a relative movement in different directions in that a mirror-symmetric change in radiation density is brought about exclusively by changing the method parameters.

Abstract: The invention is directed to a device by which two plastic parts can be welded together along their contacting joining surfaces (workpiece) quasi-simultaneously by laser radiation along a joining contour. The beam bundle emitted by a laser diode is coupled into a first gradient index lens by a light-conducting fiber. The first gradient index lens concentrates the beam bundle on a workpiece surface, this first gradient index lens being deflected relative to the exit surface of the light-conducting fiber so that the beam bundle scans a joining contour on the workpiece surface in order to heat, plasticize and weld the workpiece quasi-simultaneously. A plurality of such devices may be put together to form a more complex device in order to apply radiation to larger joining contours simultaneously and quasi-simultaneously.

Abstract: Disclosed is a method for separating optical fibers by means of CO2 laser radiation, appllicable with various types and sizes of fibers with or without cladding as well as with fiber bunches and fiber components. According to the inventive method, separation is performed by means of a special impulse regime adapted to each material, whereby minuscule volumes of material are removed along a line in a sawing-like process until complete separation has been achieved.

Abstract: A device for welding a plurality of thermoplastic plastic parts (parts to be joined) forming a hollow body with an opening by a laser, comprising a vacuum holder having a vacuum chamber which communicates with a vacuum pump, is open on one side and, together with the hollow body, forms a closed chamber that can be evacuated. When a vacuum is applied, the vacuum holder holds the hollow body stationary, holds the joined parts together and enables testing of the tightness of the weld.

Abstract: In a method for joining plastic structural component parts by laser radiation, it is the object of the invention to prevent impairment of the surface quality by the falling in of material of the quality surface in thin-walled plastic structural component parts when the latter are connected to another part. A first thin-walled plastic structural component part having a quality surface is formed so as to be absorbent for the laser radiation and is welded by the transmission radiation method on a side located opposite from the quality surface to a second plastic structural component part which is transparent to the laser radiation.

Abstract: A device for welding a plurality of thermoplastic plastic parts (parts to be joined) forming a hollow body with an opening by a laser, comprising a vacuum holder having a vacuum chamber which communicates with a vacuum pump, is open on one side and, together with the hollow body, forms a closed chamber that can be evacuated. When a vacuum is applied, the vacuum holder holds the hollow body stationary, holds the joined parts together and enables testing of the tightness of the weld.