A waveguide for plastic welding has an entry end, an exit end as well as a first and a second inner face arranged between the entry end and the exit end, which are arranged opposite to each other and by means of which laser light can be reflected. A first distance between the entry end and the exit end defines a length of the waveguide and a second distance between the first and the second inner face defines a thickness of the waveguide. The exit end may be arranged opposite to the entry end and a central plane of the waveguide may extend centrally from the entry end to the exit end. The first inner face comprises a continuously curved, concave shape so that a third distance between the first inner face and the central plane varies continuously from the entry end in the direction of the exit end.

A pyrometer device for temperature determination in laser plastic welding is provided, wherein the pyrometer device comprises: a first fiber connector for a first optical fiber; a second fiber connector for a second optical fiber; and a radiation temperature sensor; wherein the pyrometer device is adapted to forward process laser radiation received via the first fiber connector to the second fiber connector and output via the second fiber connector; wherein the pyrometer device is adapted to forward thermal radiation received via the second fiber connector to the radiation temperature sensor. Further a system for laser plastic welding with a laser beam source, process optics, and a fiber-coupled pyrometer device is provided.

An optical head for a laser transmission welding apparatus comprising a housing with an end on the outlet side with respect to a laser beam and a ball mounted in the housing. The ball may comprise a material whose refractive index is higher than the refractive index of quartz glass.

A method for sensing intensity of laser light in a simultaneous laser welding system includes placing a smart part in a weld area. The smart part includes at least a laser light intensity sensor for sensing laser light directed at it. Laser light intensity is sensed by the laser light intensity sensor of the smart part which provides an output signal indicative thereof to a controller.

A narrow waveguide homogenizes laser light traveling from a laser light source of a laser bank through a plurality of laser delivery bundles that include at least a fiber optic bundle leg to weld a plurality of work pieces along a weld line that is narrower than the width of the fiber optic bundle leg. The narrow waveguide has a portion associated with each fiber optic bundle leg that is narrower than the fiber optic bundle leg with which that portion of the waveguide is associated. A reflective bounce plane diverts laser light of the fiber optic bundle leg that does not travel through the narrow waveguide.

A curved and one-sidedly open waveguide for plastic welding, especially for laser transmission welding, includes a first reflecting element having a reflecting surface by means of which laser light can be reflected. The reflecting surface defines a receiving end at which laser light from a laser light source, in particular a light guide or a plurality of light guides, is receivable, and an output end at which laser light is directable into a laser light transmitting work piece. The reflecting surface is defined by a curve between the receiving end and the output end so that the reflecting surface of the first reflecting element has a continuously curved concave shape when viewed in cross-section. Further, the first reflecting element is not opposed by a second reflecting element so that the waveguide is open in the direction normal to the reflecting surface.

Sensors incorporated within a laser channel detect laser light upconverted by a dopant. The dopant is located after a delivery end of a laser delivery optical fiber and upconverts laser light that has traveled from a laser light source from a laser bank through one of a plurality of laser channels through to a location after the delivery end of a laser delivery optical fiber. In some embodiments, the dopant is positioned at the delivery end of the laser delivery optical fiber. In other embodiments, the dopant is positioned within a dummy part or on a surface of at least a work piece.

Sensors incorporated within a laser bank detect light emitted by light sources that is directed into and travels through a delivery end of an associated laser delivery optical fiber. The light sources may be positioned between downstream of the delivery end of the associated laser delivery optical fiber and a lower tooling. In some embodiments, the light source is incorporated within a waveguide. In other embodiments, the light source is positioned within a dummy part.

Simultaneous laser welding equipment of a vehicle light including at least a plurality of laser sources suitable for emitting light beams, a plurality of optical fibres associated, at the input ends to the at least one laser source and transmitting the light beams. A light guide is provided with at least one hollow seat that delimits a continuous perimetral contour, counter-shaped to the weld interface. The light guide comprises diffusion elements that pass through the perimetral contour of the seat of the light guide internally, so as to intercept and influence the light beams that propagate inside the seat and that are shaped to expand the light beams along a direction substantially tangent to the curvilinear abscissa defining the perimetral contour, before it projects from the light output wall and/or at the latter.

This invention provides a process and device for simultaneous laser welding; after using the moving lower die and the fixing upper die to make the base and the lens attached, by using the light pipe, for example, transparent substances or other cheap materials, to make the laser, which is emitted from the laser source, emit through the lens to a welding region of the base after being processed, to operate rapid and average heating to the welding region; meanwhile, using the welding cylinder to press the base and the lens together, to make base and the lens pressed and welded together in molten state, and when welding, it does not generate powder or other defects, and, at the same time, it can make the height H and the width w of the generated waste selvage between [0, 0.4] mm, which can improve the performance of welding object more efficiently.