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.

A laser device comprises first and second laser units to respectively emit first and second laser beams that propagate in first and second directions and that are polarized in first and second polarization directions and a polarization coupling prism arranged to couple the two laser beams. The coupling prism comprises: a light entry surface to receive the first laser beam; a reflecting surface to reflect the first laser beam at an angle greater than the limit angle of total inner reflection; and a light exit surface through which the first laser beam exits the prism. The second laser unit is arranged relative to the polarization coupling prism to cause the second laser beam to impinge on and be reflected at the light exit surface in the same direction as the first laser beam exiting the prism, resulting in a collinear superposition of the first and second laser beams.

In a fiber laser system (1) for outputting a laser beam obtained by combining a plurality of laser beams outputted by driving the respective fiber laser unit (2a, 2b, 2c), a control section (7) controls a plurality of current sources (6a, 6b, 6c) so that there are time intervals of a certain time between peaks which appear in a case where respective powers of the laser beams rise.

According to one embodiment, a laser processing method includes irradiating a region of a substrate with first laser light having a first pulse width greater than ten nanoseconds and irradiating the region substrate with second laser light having a second pulse width less than the first pulse width. In some embodiments, the region may be irradiated with the first and second laser lights simultaneously. In other embodiments, the irradiation with first laser light may occur before the irradiation with the second laser light.

Forming holes in a material includes focusing a pulsed laser beam into a laser beam focal line oriented along the beam propagation direction and directed into the material, the laser beam focal line generating an induced absorption within the material, the induced absorption producing a defect line along the laser beam focal line within the material, and translating the material and the laser beam relative to each other, thereby forming a plurality of defect lines in the material, and etching the material in an acid solution to produce holes greater than 1 micron in diameter by enlarging the defect lines in the material. A glass article includes a stack of glass substrates with formed holes of 1-100 micron diameter extending through the stack.

Multi-beam, multi-wavelength processing systems include two or more lasers configured to provide respective beams to a substrate. The beams have wavelengths, pulse durations, beam areas, beam intensities, pulse energies, polarizations, repetition rates, and other beam properties that are independently selectable. Substrate distortion in processes requiring local heating can be reduced by preheating with a large area beam at a first wavelength followed by exposure to a focused beam at a second wavelength so as to heat a local area to a desired process temperature. For some processing, multiple wavelengths are selected to obtain a desired energy deposition within a substrate.

A three dimensional printing system includes a laser system, a beam splitter, a pinhole, a sensor, and a controller. The laser system emits a light beam of varying diameter carrying at least 100 watts of optical power along an optical path. The laser has an imaging plane along the optical path which can be coincident or close to a focal plane at which the beam has a minimum diameter. The beam splitter is positioned along the optical path to receive the beam and to transmit most of the optical power and to reflect remaining optical power. The pinhole is positioned along the optical path at the imaging plane to receive the reflected beam having a minimal diameter. The controller is configured to analyze a signal from the sensor to determine intensity and distribution parameters for the light beam.

A method of laser processing a material to form a separated part. The method includes focusing a pulsed laser beam into a laser beam focal line, viewed along the beam propagation direction, directed into the material, the laser beam focal line generating an induced absorption within the material, the induced absorption producing a hole or fault line along the laser beam focal line within the material, and directing a defocused carbon dioxide (CO.sub.2) laser from a distal edge of the material over the plurality of holes to a proximal edge of the material.

Metal field 3D printers discharge metal powder over a base plate and a directable laser subsequently welds relevant points. Iteration layer-by-layer results in a shaped body which is printed using a computer model as an individual piece for rapid prototyping. The metal powder discharge, subsequent welding and final multiple iteration, however, take time, making shaped body production time-consuming. A more rapid movement of the carriage does not accelerate the process, because of metal powder turbulence occurring in the metal powder. To solve this problem, a laser is carried along on the carriage such that the welding process can be carried out directly with the passing over of the carriage. Therefore, the carriage travels more rapidly without risking turbulence and multiple layer applications are thus possible in one pass, in particular by arranging parallel laser elements and material chambers across the whole carriage width passing over the base plate.

Forming holes in a material includes focusing a pulsed laser beam into a laser beam focal line oriented along the beam propagation direction and directed into the material, the laser beam focal line generating an induced absorption within the material, the induced absorption producing a defect line along the laser beam focal line within the material, and translating the material and the laser beam relative to each other, thereby forming a plurality of defect lines in the material, and etching the material in an acid solution to produce holes greater than 1 micron in diameter by enlarging the defect lines in the material. A glass article includes a stack of glass substrates with formed holes of 1-100 micron diameter extending through the stack.