An optical beam shaping element to perform beam shaping of multi-mode laser beams where a uniform ring-shaped intensity distribution is produced at a focal length of a focusing lens. The optical beam shaping element with a surface having radial arms which are twisted to be curved in comparison to a known Siemens star beam shaper giving a spiral configuration. Embodiments are described in which each of the arms in the spiral structure is additionally modified with radially varied slope and/or curvature to optimise far field distribution. Relative rotation between two optical beam shaping elements forms an adjustable trident to vary power between the ring and a centre spot. The optical beam shaping element finds application in laser material processing were the spiral curvature removes hotspots and can be configured to improve through focus performance and input sensitivity.

A method for providing a first and a second laser beam, which are spatially offset in relation to an input laser beam. The method includes: providing a laser source for generating the input laser beam; providing a spatial offsetting unit for providing an offset laser beam that can keep the same polarization between the input laser beam and the offset laser beam; providing a separating unit including a first module for separation by polarization in order to obtain, from the offset laser beam: the first laser beam spatially offset by transmission; and the second laser beam spatially offset by reflection, the first and second spatially offset laser beams being suitable for each describing a circle.

A laser processing apparatus 1 is an apparatus for forming a modified region R in an object to be processed S by irradiating the object S with laser light L. The laser processing apparatus 1 comprises a laser light source 2 that emits the laser light L, a mount table 8 that supports the object S, and an optical system 11 that converges a ring part surrounding a center part including an optical axis of the laser light L in the laser light L emitted from the laser light source 2 at a predetermined part of the object S supported by the mount table 8. The optical system 11 adjusts a form of at least one of inner and outer edges of the ring part of the laser light L according to a position of the predetermined part in the object S.

The invention concerns an apparatus and a method for laser processing. There is provided at least one first laser beam from at least one first optical feed fiber connected to at least one first laser device and at least one second laser beam from at least one second optical feed fiber connected to at least one second laser device. Said first and second laser beams are combined in a multi-core optical fiber. Said first core of said multi-core optical fiber has a circular cross-section, and said second core has an annular shape concentric to said first core. A composite laser beam comprising first and second output beams is directed from said multi-core optical fiber to a workpiece with overlapping elements to be welded.

Apparatus for laser processing a material (11), comprising a laser (1), an optical fibre (2), and a coupler (125), wherein: the laser (1) is connected to the optical fibre (2); the optical fibre (2) is a multimode optical fibre having a first optical mode (21) having a first mode order (24), a second optical mode (22) having a second mode order (25), and a third optical mode (23) having a third mode order (26); the third mode order (26) is higher than the second mode order (25) which is higher than the first mode order (24); the coupler (125) switches laser radiation propagating in the first optical mode (21) to laser radiation propagating in the second optical mode (22); and the coupler (125) switches the laser radiation propagating in the second optical mode (22) to laser radiation propagating in the third optical mode (23).

A method for laser processing a transparent workpiece includes forming a contour line in the transparent workpiece and directing an infrared laser beam output by an infrared beam source through an a focal beam adjustment assembly and onto the transparent workpiece along the contour line to separate the transparent workpiece along the contour line. The infrared laser beam forms an annular infrared beam spot on a surface of the transparent workpiece. The infrared laser beam includes an entrance beam diameter upstream the afocal beam adjustment assembly and an exit beam diameter downstream the afocal beam adjustment assembly. The annular infrared beam spot includes an inner diameter, an outer diameter, and an annular thickness. Further, the focal beam adjustment assembly includes one or more adjustable optical elements. Moreover, adjusting the one or more adjustable optical elements alters the exit beam diameter, thereby altering the annular thickness of the annular infrared beam spot.

The device comprises a welding unit with a tube (3), a laser radiation unit (1) radiating in direction of the tube axis (3.0), and a mandrel (4) which is connected to the tube (3) via a holding unit which is formed, e.g., by two spacer elements (5.1) and which is coaxially arranged relative to and in the tube (3). The tube (3) and the circumferential surface of the mandrel (4) are reflective of the laser radiation of the laser radiation unit (1) such that through multiple reflections between the tube (3) and the mandrel (4) the laser radiation is deflected toward the beam output-side tube end (3.2) and is shaped annularly.

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.

The present invention relates to an apparatus and a method for thermal processing within a processing region (1) at a workpiece surface (2) by means of a laser beam (6) emitted by at least one radiation source (5). Arranged in the beam path of the laser beam (6) between the at least one radiation source (5) and the processing region (1) on the workpiece surface (2), there is at least one element (10, 11, 12) by means of which the intensity of the laser beam (6) is modifiable in a locally defined manner within the processing region (1). As an alternative or in addition thereto, the intensity of at least one of the laser beams (6) is modifiable in a locally defined manner within the processing region (1) by a defined actuation of the plurality of radiation sources (5) such that a locally defined distribution of the intensity of the laser beam (6) striking the workpiece surface (2) is achievable within the processing region (1).

A laser processing machine includes a convex lens having a positive focal length, a concave lens having a negative focal length, and a focusing lens having a positive focal length. The convex lens is movable in an optical axis direction and converts divergent light of a laser beam emitted from a laser beam emission end into convergent light. The concave lens is movable in the optical axis direction and is disposed at a position that is shifted from a position where the convergent light is focused toward the convex lens side by the same distance as the focal length of the concave lens according to a position of the convex lens in the optical axis direction. The concave lens converts the convergent light into parallel light. The focusing lens focuses the laser beam emitted from the concave lens and irradiates a plate material with the focused laser beam.