IPG PHOTONICS CORPORATION

A laser system and method. In one example, the laser system includes an optical pulse stretcher configured to stretch pulse durations of an input train of input pulses to produce a train of stretched laser pulses, a pulse replicator module configured to increase a pulse repetition rate of the train of stretched laser pulses to produce a modified pulse train of laser light, a fiber power amplifier configured to amplify the modified pulse train to produce amplified laser pulses, and a pulse compressor that temporally compresses the amplified laser pulses to produce amplified and compressed laser pulses. The system may further include a nonlinear frequency conversion stage comprising at least one nonlinear crystal.

The disclosed laser welding system is adapted for welding overlapping coated metal sheets, e.g. Zi- or Zi-alloy coated steel sheets. The disclosed welding system comprises a laser source producing OW or QCW laser beam, a laser beam delivery cable delivering the laser beam to a laser head of the welding system, wherein the laser head is equipped with a hollow pressure piece adapted to press against the surface of the first metal sheet and simultaneously to deliver the laser beam to the surface of the first metal sheet through the hollow pressure piece to create dimples on the surface of the first metal sheet. The hollow pressure piece of the laser head is also adapted to press against the surface of the second metal sheet positioned on the surface of the first metal sheet with the dimples during the step of seam welding the first and the second metal sheets. According to the invention, the power of the laser beam is reduced during the pre-processing dimpling step comparing to the laser beam power during the seam welding processing step.

A beam shaper includes upstream and downstream fibers fused together at a splice angle different from a zero angle and controllably increased to provide a transformation of a Gaussian intensity distribution profile at an input of the upstream fiber to an intensity distribution profile including one of flattop, inverse Gaussian and donut-shaped profiles at an output of the downstream fiber. The fibers are selected from SM, MM passive and active fibers with the downstream fiber being a multimode fiber.

Steering handles with manifolds that enable an operator to configure an endoscopic system in situ for a variety of tasks, including irrigation, aspiration, or both. In addition, the disclosed endoscopic systems facilitate rapid reconfiguration of the location of a laser fiber optic within a catheter assembly. The laser fiber optic, for example, can be removed from an irrigation channel of the endoscopic system and reinserted in the aspiration channel during a laser lithotripsy procedure. In some embodiments, the removal and reinsertion can be performed in situ, without removing the catheter from the patient or the treated organ. These aspects of the disclosed system reduce the time required to perform laser lithotripsy procedures, with less trauma to the patient.

Controlling a low-threshold femtosecond supercontinuum (fs SCG) in a bulk nonlinear material (BNLM) with a positive thermo-optic coefficient (dn/dT>0 K −1 ) is provided by coupling light at a first wavelength output by a fs oscillator at a full pulse repetition PRR into the BNLM. The coupling of light produces a nonlinear lens of the coupled beam in the BNLM which is insufficient to provide intensity of the light sufficient to reach ta threshold of the fs SCG. To raise the pulse energy and reach the SCG threshold, light at a second wavelength different from the first wavelength is absorbed in the BNLM to form a thermal lens in the BNLM which assist the nonlinear lens in creating the SCG.

Systems and methods for on-the-fly (OTF) welding using optical coherence tomography (OCT) use measurement and compensation techniques to ensure accuracy of OCT measurements. OTF welding may involve a coordinated motion of a process beam by the process beam head while the process beam head is moved relative to the workpiece to perform, for example, linear OTF welding, rotary OTF welding, or infinite FOV welding. The systems and methods described herein may be used to perform OTF welding in different applications including, for example, in EV battery manufacturing applications for welding battery cells and busbars. OCT may be used to monitor the OTF welding process using an OCT measuring beam directed to the workpiece with the process beam.

A beam combiner configured to spectrally combine multiple beams includes at least one pair of identically configured TVBGs. The TVBGs are spaced apart along a light path and aligned at respective “+” and “−” Bragg angles. The upstream TVBGs diffracts a first beam, which is incident thereon at one of the Bragg angles, so that spectral components of this beams diverge from one another defining thus a fan-shaped beam at the output of the upstream TVBG. Upon launching the diffracted first beam to the downstream TVBG at the other Bragg angle, its spectral components again are diffracted but in the direction opposite to that provided by the upstream TVBG. Thus, the dispersion effects in respective TVBGs cancel out each other. Another beam is incident on and transmitted by the downstream TVBG which combines the twice diffracted and transmitted beams into a collimated combined beam.

A high-power laser system includes at least one high-power laser source outputting a substantially single mode (SM) beam. The SM beam is coupled into a reflective volume Bragg grating (RVBG) made of material which absorbs the SM beam to induce a first thermal lens (TL). Upon reflecting, the beam exits the RVBG through the first TL and is coupled into an optical compensator made from material different from that of the first TL and inducing a second TL. The second TL is configured to have a power opposite to that of the first TL matching to that of the first TL to least partially compensate a heat induced thermal degradation of the reflected beam by the first TL.

The DCS includes a pair of optical frequency combs (FC) which generate respective outputs at different pulse repetition frequencies (PRF) in a monitoring regime mode characterized by free running FCs. The outputs are combined in a single output which is split between sample-investigating (SI) and reference channels with the latter including a cell with etalon material which has a known etalon spectrum at low pressure. The etalon spectrum contains one or more broadly spaced apart, high intensity narrow molecular lines. Upon interacting with one of the beams, the cell emits a cell signal detected by a photodetector. The cell signal is processed in a data processing unit operative to mathematically filter out a single molecular line of the etalon spectrum and correct the phase change in the filtered line. The corrected phase change is used to restore the desired spectrum of the cell signal and further the desired spectrum of the SI signal.

A nozzle assembly for performing material processing operations with a handheld laser system on a surface of a workpiece. The handheld laser system comprises a laser source configured to generate laser radiation, a handheld device that guides the laser radiation, and an optical fiber coupling the handheld device to the laser source, and the nozzle assembly comprises a nozzle configured to deliver the laser radiation to the surface, and a coupling mechanism that includes a retaining portion formed on an output end of the handheld device, and an engagement portion configured to be releasably attachable to the nozzle and engage with the retaining portion. A rearward ring provides a first initial coupling with the handheld device and an intermediate ring is rotated to provide a final coupling where the nozzle is non movably secured to the handheld device.