A method for laser keyhole welding of metal alloys is disclosed. The method independently adjusts power in a focused center beam and power in a concentric focused annular beam. At the termination of a weld, the power in the center beam is initially ramped up and then ramped down, while the power in the annular beam is ramped down. Increasing the power in the center beam enables a controlled and prolonged contraction of the keyhole and melt pool, thereby preventing undesirable cracking.

Disclosed is a hybrid additive manufacturing system that includes a laser system and an additive manufacturing tool, such as an arc welding type torch. The tool is configured to receive a metallic electrode wire, which is heated by a power supply to create droplets for deposition to create the part by building up successive layers of metal. The additive manufacturing system operates through coordination of the laser system to generate a laser beam, which is applied to a weld bead, and an arc welding process, which provides material for the part. A threshold value of laser intensity and/or power can be applied to the weld puddle to stabilize the arc. Through the laser beam, an arc cone position can be manipulated such that the energy into the molten pool can be redistributed.

A laser uniformly machining apparatus and method thereof are provided. The apparatus includes a laser unit, a shaping element, a collimating element, a scaling element and a focusing element. The laser unit provides a laser beam for machining. The shaping element shapes the laser beam into an annular beam. The collimating element modifies the direction of the annular beam in accordance with the direction of an optical axis to turn the annular beam into a collimated annular beam. The scaling element adjusts the collimated annular beam in accordance with a scaling ratio to produce a scaled annular beam. The focusing element focuses the scaled annular beam. The scaled annular beam is produced by the scaling element to form a focused beam having a uniformly distribution of light intensity in the direction of the optical axis.

An apparatus, comprising: a multi-clad fiber comprising a light-guiding core surrounded by at least a further cladding layer around the guiding core, an input interface comprising a first set of input channels in the core configured to receive at least a first optical fiber and a second set of input channels in the at least a guiding cladding layer configured to receive at least a second optical fiber. The apparatus further comprises: an optical switch module comprising an input port, a first and a second output port, a first optical path between the input port and the first input channel in the first set of input channels in the core via the first output port, and at least a second optical path between the input port and a second input channel in the second set of input channels in the at least one guiding cladding layer via the second output port, the optical switch module being controllable to switch between the first and the second optical paths, a set of laser modules comprising at least one first and second laser module, the laser modules configured to emit respective laser beams when in a respective power-on state, the first laser module being coupled to an input channel in the first set of input channels via the at least a first optical fiber, the second laser module being coupled to the optical switch module.

The invention relates to a beam forming lens system for machining material using a laser beam, comprising a two-dimensional axicon array (10) featuring a plurality of microaxicons (11) for creating an annular laser beam intensity profile, the microaxicons (11) being provided with curved lateral surfaces (113). The invention also relates to an apparatus for machining material using a laser beam, comprising a beam forming lens system of said type and a focusing lens system (15) for focusing the laser beam onto a workpiece (18). The beam forming lens system is designed to create the annular laser beam intensity profile in a focal plane (F) of the focusing lens system (15).

A profile selector includes at least one beam-forming lens refracting a laser beam to be incident so as to convert a beam profile and emits a laser beam having a beam profile selected from a plurality of beam profiles. A collimating lens converts a laser beam of a divergent beam to be incident into collimated light. A focusing lens focuses the collimated light emitted from the collimating lens and irradiates the focused beam to a sheet metal of a processing target. A moving mechanism moves the collimating lens along an optical axis such that a deviation of a focal point is reduced caused when the beam profile of the focused beam emitted from the focusing lens is selected by the profile selector.

A method for controlling surface asperity during laser sealing of a membrane vent hole. The method includes applying a laser pulse having a laser intensity spatial distribution to the membrane vent hole to form a seal over the membrane vent hole. The seal has a seal surface. The laser pulse includes a primary laser pulse region and a secondary laser pulse region beginning once the primary laser pulse region ends. The primary laser pulse region has a primary laser power, and the secondary laser pulse region has a secondary laser power. The secondary laser power is less than the primary laser power. The seal surface has a controlled surface asperity characteristic.

Systems and methods for laser drilling provide laser beam energy modification to reduce (e.g., eliminate or minimize) back-wall strikes during laser drilling. The systems and methods modify the process laser beam energy such that a beam energy at a central region of the process laser beam is less than a beam energy at an outer region of the process laser beam. In one example, the modified process beam has zero beam energy at the central region, thereby providing a donut mode. The laser beam energy modification may be achieved by detuning a fiber coupler in the Z axis such that laser energy is coupled into a cladding layer of the process fiber coupled to the laser fiber via the fiber coupler.

A laser processing apparatus includes a light source configured to generate a laser beam, and a light converging optical system configured to converge laser beam to a focal point at an object to be processed, the light converging optical system including a through-hole optical element and a composite optical element under the through-hole optical element, wherein the through-hole optical element includes a first recess portion configured as a concave mirror at a lower surface of the through-hole optical element, and wherein an upper surface of the composite optical element is convex and includes a first region configured to reflect the laser beam and a second region configured to transmit the laser beam.

The present disclosure provides a device and a method for laser-based separation of a transparent, brittle workpiece, comprising a laser that emits a laser beam having an intensity (I.sub.L) along an optical axis (P), and an optical device. The optical device has at least one one-piece double axicon. The double axicon has an entrance surface and the optical device has an exit surface. The entrance surface is such that in the double axicon, a ring beam is formed. The intensity (I.sub.L) in the double axicon is lower than the threshold intensity (I.sub.S) of the material of the double axicon. The exit surface is such that a line focus having a maximum intensity (I.sub.max) and a length (L.sub.T) is generated in the direction of the laser beam behind the exit.