A method for manufacturing a large-area volume grating includes: (1) splitting a laser beam into two or more laser beams, converging the two or more laser beams into a sample at an angle less than 60° to form a first plasma grating; (2) moving the sample in a longitudinal direction of a plane vertical to the first plasma grating to etch out a first prefabricated volume grating; (3) moving the sample laterally to form a second plasma grating, an effective cross section of the first prefabricated volume grating partially overlapping with that of the second plasma grating, then moving the sample in a longitudinal direction of a plane vertical to the second plasma grating to etch out a second prefabricated volume; and (4) repeating steps (2) and (3) n times to obtain a volume grating in any size.

The present invention relates to a laser apparatus using optical fibers for stable laser welding and a laser welding method using same. Hybrid ring mode-shaped laser beams, in which a central beam using fiber laser is positioned at the center of outer beams using diode laser, are used to perform welding by irradiating a to-be-welded portion of an object with the outer beams, the central beam, and the outer beams in this order. Thus, since the welding is performed using the central beam as a heat source in a state in which the to-be-welded portion of the object has been heated with a sufficient amount of heat input, the temperature gradient of the to-be-welded portion is low and solidification cracking does not occur. Also, problems such as spatter and voids can be minimized, and the laser welding is stable, and thus a quality of welding that is uniform and stable overall can be obtained.

There is provided an optical axis alignment mechanism between the laser oscillator and the optical fiber. The laser oscillator emits laser light, which then emerges from the emission end of the optical fiber via the axis alignment mechanism. Part of the laser light is received on the light-receiving surface of the CCD camera of a laser light evaluator. Thus, the laser light evaluator acquires a light intensity distribution. The light intensity distribution is used by the optical axis alignment mechanism to align the axis of the laser oscillator with the axis of the optical fiber.

A system that uses a scalable array of individually controllable laser beams that are generated by a fiber array system to process materials into an object. The adaptive control of individual beams may include beam power, focal spot width, centroid position, scanning orientation, amplitude and frequency, of individual beams. Laser beam micro scanner modules (MSMs) are arranged into 2D arrays or matrices. During operation of the MSMs, a fiber tip that projects the laser beam is displaced along the x and y-axis in order to scan the focal spot. Each MSM within a matrix can process a corresponding cell (e.g., one square centimeter) during focal spot scanning, and the plurality of MSMs may be operated in parallel to process a plurality of corresponding cells (e.g., with a 10×10 matrix of MSM, 100 cm.sup.2) without rastering or otherwise repositioning the assembly over the build surface.

A nozzle structure for discharging printing material onto a substrate is presented. The nozzle structure comprises a tubular member having a distal part that faces the printing plane when in operation and defining an elongated inner cavity along the tubular member for placement a filament printing material. The tubular member comprises light input ports on the proximal part thereof for directing light toward inner surfaces thereof. The tubular member has an elongated tube portion and a distal tip portion at the distal part thereof, configured and operable as a light guide trapping and guiding the input light along the tubular member in a general direction toward the distal part, thereby continuously transferring light field to distal regions of the elongated inner cavity. The distal tip portion is configured to allow the trapped light to escape towards the printing plane, thereby heating a location on the printing plane facing the nozzle.

A system that uses a scalable array of individually controllable laser beams that are generated by a fiber array system to process materials into an object. The adaptive control of individual beams may include beam power, focal spot width, centroid position, scanning orientation, amplitude and frequency, of individual beams. Laser beam micro scanner modules (MSMs) are arranged into 2D arrays or matrices. During operation of the MSMs, a fiber tip that projects the laser beam is displaced along the x and y-axis in order to scan the focal spot. Each MSM within a matrix can process a corresponding cell (e.g., one square centimeter) during focal spot scanning, and the plurality of MSMs may be operated in parallel to process a plurality of corresponding cells (e.g., with a 10×10 matrix of MSM, 100 cm.sup.2) without rastering or otherwise repositioning the assembly over the build surface.

Laser processing systems and methods image a multiple core array to a work surface in a multiple processing beam array. An optical system separates processing beams and converges the beams toward the work surface and focuses each beam of the array at or near the work surface. A central axis with access for filler material flow to the work surface is provided. The processing beam array and central filler material feed provide omni-directional additive laser processing capability.

A method includes forming a plurality of semiconductor regions on a wafer, placing the wafer in an etching chamber, globally heating the wafer using a heating source, and projecting a laser beam on the wafer. When the wafer is heated by both of the heating source and the laser beam, the plurality of semiconductor regions on the wafer are etched.

A laser welding optical apparatus includes: a laser beam source; a collimation optical unit collimating the provided laser beam; a beam splitter splitting the collimated laser beam into partial beams, the beam splitter having a first setting facility, which variably sets the splitting of the collimated laser; and a focusing optical unit focusing the partial beams onto the welding workpiece The laser beam source has a multiclad fiber having a core and ring fiber, and a second setting facility, which variably splits an input laser beam at an end of the multiclad fiber between the core and ring fiber. A second end of the multiclad fiber provides the laser beam for the collimation optical unit. The beam splitter splits the collimated laser beam among two leading and trailing partial beams. The first setting facility sets the energy distribution between the leading and the trailing partial beams.

An additive manufacturing system is disclosed that comprises two or more lasers for precisely heating a fiber-reinforced thermoplastic feedstock and a fiber-reinforced thermoplastic workpiece in preparation for depositing and tamping the feedstock onto the workpiece. The system employs feedforward, a variety of sensors, and feedback to ensure that the feedstock and workpiece are properly heated.