A method for laser keyhole welding a stack of metal foils to a metal tab is disclosed. The method independently adjusts power in a focused center beam and power in a focused annular beam to form a weld through all the foils and the tab. The annular beam provides sufficient power to heat the metal to about melting temperature, widen a mouth of a keyhole, and stabilize a melt pool. The center beam provides sufficient additional power to form the keyhole. The power of the annular beam is sustained for a longer time than the power of the center beam. A plurality of such welds is formed to provide mechanical strength and electrical conductivity.

Laser ablation devices that utilize beam profiling assemblies to clean and process surfaces are described herein. A method includes directing a laser beam in a geometrical pattern at an arcuate surface of a cylindrical target, blocking a portion of the laser beam to prevent a portion of the geometrical pattern from contacting the cylindrical target, and rotating the cylindrical target as the laser beam contacts the arcuate surface so as to ablate the cylindrical target.

A welding method includes: emitting laser beam toward a workpiece including a metal to melt and weld a part of the workpiece, the part being where the laser beam has been emitted to. Further, the laser beam includes a main power region and at least one auxiliary power region, a power of the main power region is larger than a power of each of the at least one auxiliary power region, and a ratio between the power of the main power region and the total of powers of the at least one auxiliary power region is in a range of 144:1 to 1:9.

A thin layer etching apparatus includes an etchant supply unit configured to supply an etchant onto a substrate to etch a thin layer formed on the substrate, a temperature measuring unit configured to measure a temperature of the substrate while an etching process is performed by the etchant, a laser irradiating unit configured to irradiate a first laser beam on a first portion including a central portion of the substrate and to irradiate a second laser beam in a ring shape on a second portion surrounding the first portion so that the temperature of the substrate is maintained at a predetermined temperature during the etching process, and a process control unit configured to control power of the first and second laser beams based on the temperature of the substrate measured by the temperature measuring unit to reduce a temperature difference between the first and second portions of the substrate.

Provided are a laser cutting device and a laser cutting method. The laser cutting device comprises a beam expanding element provided with a plurality of lens wherein optical axes of the plurality of lens sets are located in the same line and each lens set comprises at least one lens; the beam expanding element converts an incident beam into a first beam; and a laser splitting element and the first beam are arranged in an emitting optical path of the beam expanding element, and the laser splitting element converts the first beam into a plurality of second beams spaced from one another. In the laser cutting device, by means of providing the laser splitting element, the first beam is converted into the plurality of second beams, so as to obtain the effect of beam adjustment.

A method of laser processing including generating a laser beam having, at different longitudinal positions in a propagation direction, first and second transverse beam profiles of energy density. The first transverse beam profile is different to the second transverse beam profile and is non-Gaussian. The method includes carrying out a scan of the laser beam across a working surface, wherein, during the scan, the laser beam and/or working surface is adjusted such that, for a first part of the scan, the first transverse beam profile is located at the working surface and, for a second part of the scan, the second transverse beam profile is located at the working surface.

A method for laser processing a transparent workpiece includes focusing a pulsed laser beam output by a pulsed laser beam source into a pulsed laser beam focal line directed into the transparent workpiece, thereby forming a pulsed laser beam spot on the transparent workpiece and producing a defect within the transparent workpiece, directing an infrared laser beam output onto the transparent workpiece to form an annular infrared beam spot that circumscribes the pulsed laser beam spot at the imaging surface and heats the transparent workpiece. Further, the method includes translating the transparent workpiece and the pulsed laser beam focal line relative to each other along a separation path and translating the transparent workpiece and the annular infrared beam spot relative to each other along the separation path synchronous with the translation of the transparent workpiece and the pulsed laser beam focal line relative to each other.

A ring focus optics for machining rotationally symmetrical or nearly rotationally symmetrical workpieces by an annular laser beam includes a conical mirror configured to deflect the annular laser beam radially inward or outward onto a circumference of at least one workpiece, a rotational axis of which is aligned collinear to an optical axis of the ring focus optics. The ring focus optics further includes a holding/centering device surrounded by the annular laser beam and fastened on the housing of the ring focus optics. The holding/centering device is configured to axially fix the at least one workpiece and/or to radially center the at least one workpiece with respect to the optical axis.

A deposition method is provided wherein a donor substrate (10) is arranged opposite a target substrate (20), the donor substrate having a surface (12) facing the target substrate that is provided with a viscous donor material (14). An optical beam (30) is directed via the donor substrate to the donor material so as to release the donor material and to therewith transfer the donor material as a jet towards the target substrate. In the method provided herein an input signal (D.sub.S) is received that specifies a shape to be assumed by the jet with which the donor material is to be transferred and an energy profile of the optical beam is accordingly controlled. Additionally or alternatively the energy profile of the optical beam may be controlled in accordance with a pattern according to which the donor material is to be deposited on the target substrate. Likewise a corresponding deposition apparatus is provided.

A method for butt laser welding two metal sheets (2, 4) includes providing a first metal sheet (2) and a second metal sheet (4) and butt welding the metal sheets (2, 4) along a direction of welding. The butt welding step includes simultaneously emitting a first front laser beam (12) creating a first front spot (18) at the intersection with the first metal sheet (2), and generating a first front keyhole (19) in the first metal sheet (2) at the first front spot (18); a second front laser beam (14) creating a second front spot (20) at the intersection with the second metal sheet, and generating a second front keyhole in the second metal sheet (4) at the second front spot (20); and a back laser beam (16) creating a back spot (22) on the first and second metal sheets (2, 4), and generating a back keyhole (23A) in the first and second metal sheets (2, 4) at the back spot (22). The first and second front laser beams (12, 14) and the back laser beam (16) are configured in such a manner that at each moment in time, a solid phase region (25) and/or a liquid phase region (13, 23B) of the metal sheets (2, 4) remains between the first front keyhole (19) and the back keyhole (23A) and between the second front keyhole and the back keyhole (23A).