The invention provides a method for laser modification of a sample to form a modified region at a target location within the sample. The method comprises positioning a sample in a laser system for modification by a laser; measuring tilt of a surface of the sample through which the laser focusses; using at least the measured tilt to determine a correction to be applied to an active optical element of the laser system; applying the correction to the active optical element to modify wavefront properties of the laser to counteract an effect of coma on laser focus; and laser modifying the sample at the target location using the laser with the corrected wavefront properties to produce the modified region.

A method and system for detecting an operating condition of an optical element along a propagation path of a power laser beam in a laser processing machine head are based on a first signal of a back-propagating optical radiation at the wavelength of the laser beam; a second signal of a back-propagating optical radiation having a wavelength in the near infrared; a third signal of an optical radiation emitted by the optical element in the infrared in proximity to its surface; a fourth signal which is a function of the time-of-flight of an acoustic wave launched through the volume of the optical element.

An irradiation system includes: a first beam source configured to output a first laser beam and a second beam source configured to output a second laser beam, in which the second laser beam has a higher beam quality higher than that of the first laser beam;

optics arranged to focus the first and second laser beams; and a beam guiding system including a first beam path along which the first laser beam is guided, and a second beam path along which the second laser beam is guided, in which the beam guiding system includes a beam combiner to superimpose the first and second laser beams, the first beam source is a pump laser, the second beam source is a laser resonator, and the beam guiding system further includes a beam switch adapted to feed the first laser beam into a pump laser beam path and/or into the first beam path.

There is provided an optical axis adjustment jig including a flat parallel-surface plate having an upper surface and a lower surface with reflective films disposed respectively thereon, and an image capturing unit disposed beneath the flat parallel-surface plate for capturing an image of a laser beam applied thereto. The flat parallel-surface plate is made of a material that is transmissive of a wavelength of the laser beam. The laser beam is applied through the flat parallel-surface plate to the image capturing unit. A tilt of the optical axis of the laser beam is detected on the basis of the shape of the beam spot of the laser beam whose image has been captured by the image capturing unit.

Various embodiments of the teachings herein include a method for determining a radiation intensity and/or a wavelength of a process light, wherein the melt pool underlying the process light can be generated by irradiating a metal material with an energy beam along a path, wherein the energy beam can be moved in accordance with a power profile along the path. The method may include: providing a power profile for a section of the path as an input variable for a machine learning model; training the model using historical and/or synthetic power profiles and associated historical or synthetic radiation intensities and/or wavelengths of the process light for the metal material; and determining the radiation intensity and/or the wavelength of the process light as an output variable of the model.

An apparatus for laser processing of very wide non-woven fabric materials at high speeds. This invention enables a laser beam to sever, perforate and pattern a large piece of fabric materials planarly disposed at regular or irregular spatial intervals over the entire width while the fabric passes from one roller to another roller at high speeds by precisely managing focus and intensity of the beam at the focal point on the web. A control system managing the laser processing system enables rapid reconfiguration of perforation patterns. The fabric can be woven or nonwoven, homogeneous or nonhomogeneous material with uniform or nonuniform thickness. An optical sensor is provided to sense the laser processing as it is performed and provide feedback to a system controller to optimize laser processing performance in real time.

A laser irradiation apparatus (1) according to an embodiment includes an optical-system module (20) configured to apply laser light (L1) to an object to be irradiated, a shield plate (51) in which a slit (54) is formed, through which the laser light (L1) passes, and a reflected-light receiving component (61) disposed between the optical-system module (20) and the shield plate (51), in which the reflected-light receiving component (61) is able to receive, out of the laser light (L1), reflected light (R1) reflected by the shield plate (51).

A device for determining a focus position of a laser beam in a laser machining system includes an optical element configured to reflect a portion of the laser beam for coupling out a first sub-beam of the laser beam, a spatially resolving sensor to which the first sub-beam can be directed, and an evaluation unit configured to determine a focus position of the laser beam based on an actual diameter of the first sub-beam incident on the spatially resolving sensor, a laser beam power, and calibration data.

A laser machining method includes the steps of: outputting a laser beam to the workpiece at a laser power low enough not to melt or oxidize the workpiece to measure reflected light of the laser beam; selecting a laser power suitable for melting or oxidizing the workpiece based on a measured value of the reflected light; determining whether or not the workpiece can be melted or oxidized based on the selected laser power; when the workpiece can be melted or oxidized, outputting a laser beam to the workpiece at a laser power high enough to melt or oxidize the workpiece; outputting again a laser beam to the workpiece at the low laser power to measure reflected light of the laser beam; and checking the degree of the melting or oxidization of the workpiece based on a measured value of the reflected light to determine whether or not to start laser machining.

A focusing state measuring apparatus for measuring a focusing state of a working apparatus with respect to a target object so as to perform work includes: a base plate installed in the working apparatus performing work on the target object and spaced apart from the target object; a first line beam generation unit provided on one side of the base plate and configured to irradiate a first line beam toward the target object; and a second line beam generation unit provided on one side of the base plate so as to be spaced apart from the first line beam generation unit in a first direction and configured to irradiate a second line beam toward the target object. The focusing state of the working apparatus with respect to the target object is determined according to states of the first line beam and the second line beam.