35 results about "Pulsed laser radiation" patented technology

An additive manufacturing method includes applying a layer of building material on a support or a layer of building material that has been previously selectively solidified, selectively solidifying the layer of building material by supplying laser radiation to positions in the layer that are assigned to a cross-section of the object in this layer in that these positions are scanned with a laser beam along a number of trajectories in order to melt the building material along these trajectories, and repeating the two steps of applying a layer and solidifying said layer until the cross-sections of the object that are to be manufactured by additive manufacturing have all been selectively solidified. Pulsed laser radiation is used for melting the building material and the laser beam can be moved across the layer of building material with a speed exceeding 1000 mm / s.

The present invention relates to a method and to a device for correcting the shape of an optical component (1) using pulsed laser radiation. For this purpose, the component (1) is measured and excess material (7) is determined by way of comparison with a target geometry (6) and is at least partially removed by machining using at least one pulsed laser beam (4) with pulse durations of > 1 μs in order to at least approximate the actual geometry (5) to the target geometry (6). During machining, the component (1) is rotated at a rotational speed about an axis of rotation, wherein the distance of the laser beam (4) to the axis of rotation is changed at least temporarily. The rotational speed, the beam diameter of the laser beam (4) on the component (1) and the temporal pulse interval between the pulses of the laser beam (4) are selected such that material regions of the component (1) removed by successive pulses of the laser beam (4) do not overlap.

The disclosure relates to an optical system comprising a laser source (1) which generates pulsed laser radiation consisting of a temporal sequence of laser pulses in an input laser beam (EL), a splitting element (2) which follows the laser source (1) in the course of the beam and splits each of the laser pulses into laser pulse replicas separated spatially and / or temporally from one another, a combination element (4) which follows the splitting element (2) in the course of the beam and superimposes the laser pulse replicas in a respective laser pulse in an output laser beam. It is the task of the disclosure to provide an improved optical system compared to the prior art. It should be possible to generate particularly short and thus spectrally broadband laser pulses of high power with the optical system. The disclosure proposes that at least one multipass cell (3) is arranged in the beam path between the splitting element (2) and the combination element (4), through which the laser pulse replicas propagate, wherein the multipass cell (3) contains a medium in which the laser pulse replicas undergo nonlinear spectral broadening.

The invention discloses a preparation method of all-inorganic perovskite nanocrystals based on liquid phase pulse laser induction, belonging to the technical field of perovskite luminescent materials. The preparation method is: using Cs2CO3 and PbBr2 as reaction precursors, adding n-hexane, oleic acid and oleylamine, and performing irradiation reaction under a 1064nm pulse laser beam; the product after the irradiation reaction is centrifuged once to obtain a supernatant, and the supernatant is centrifuged twice to obtain a solid product perovskite nanocrystal. The invention successfully prepares all-inorganic perovskite nanocrystals with high fluorescence quantum yield under the condition of no inert gas protection by using liquid phase pulse laser radiation technology.

The invention relates to a method for producing a hollow structure (28) in a workpiece (25) in the form of a substrate for a mirror, in particular for an EUV mirror (M4), by material removal using pulsed laser radiation (35), comprising: illuminating the workpiece (25), which is made of a material transparent to the pulsed laser radiation (35), from a radiation entry side (27), focusing the pulsed laser radiation (35) in a focus area (39), forming a removal front (46) for the planar removal of material from the workpiece (25) by moving the focus area (39) along a movement pattern (41), and producing the hollow structure (28) by moving the removal front (46) within the workpiece (25), wherein a removal front (46) is formed at least temporarily during the production of the hollow structure (28).which is not oriented perpendicular to an incident direction (Z) of the pulsed laser radiation (35) on the radiation entry side (27) of the workpiece (25), and wherein the hollow structure is created in the form of a channel through which a fluid can flow. The invention also relates to a mirror, in particular an EUV mirror, and an EUV lithography system.

An erbium fiber laser produces a beam of ultrashort laser pulses having a center wavelength greater than 780 nanometers, an average power greater than 0.5 watt, and a pulse duration less than 200 femtoseconds. The fiber laser includes an erbium fiber amplifier that is energized by a pump beam having a pump wavelength longer than 1520 nanometers. The pump wavelength is selected to provide uniform gain over the broad spectral bandwidth of a seed beam and minimal gain at shorter wavelengths in the fiber amplifier, thereby overcoming gain narrowing and gain shifting. The pump beam has sufficient power to achieve pump saturation in the fiber amplifier.

A method for producing a composite material of metal and plastic to form a plastic-metal hybrid component, in which macroscopic undercuts with microscopic undercuts having stochastically random roughness shapes and depths are introduced into the metal surface by means of short-pulse laser radiation to improve the adhesion between the metal surface and at least one plastic component, wherein the shapes and depths of the laser structuring of the metal surface are produced by changing the guidance and / or speed of the laser beam movement and simultaneously adjusting the power and / or the repetition rate of the short-pulse laser radiation, and the stochastically random roughness shapes are each at least partially filled with the at least one plastic component in an injection molding process such that the latter is gripped in the macroscopic and / or microscopic undercuts.wherein, following the roughening of the metal surface prior to the injection molding process of the at least one plastic component, at least the roughened surface of the metal is heated to a temperature which, in the processing range from room temperature to 100°C, is above the processing temperature of the at least one plastic component.

A method for laser processing of workpieces in liquid, the method including the following steps:providing a workpiece in a process chamber filled with a liquid;focusing pulsed laser radiation on a surface of the workpiece using a focusing unit;producing a relative movement between the focused laser radiation and the workpiece surface using a positioning unit;detecting a gas bubble in a predefined detection region using a detection unit; andconducting a first action to avoid or reduce interaction effects between the laser radiation and the detected gas bubble.

Wavelength-tunable source of pulsed laser radiation for VIS-NIR spectroscopy which consists of a pump source (1) forming bursts of picosecond pulses of high pulse repetition rate, and a synchronously pumped optical parametric oscillator (2). The pump source (1) comprises a solid-state regenerative amplifier (31) having one or two electro-optical switches (32,33) inside its resonator (44). The switches create partial transmission of the resonator for a time interval longer than a resonator roundtrip time, and eject a part of energy of a pulse circulating inside. Bursts of 5-10 ns duration are formed, which are filled with high peak power picosecond pulses. Pulse repetition rate of the order of GHz of pump pulses allows the construction of a compact optical parametric oscillator. The whole set of parameters ensures high energy efficiency, stability and an ability to provide output pulse bursts repeating at up to 10 kHz repetition rate.

The invention relates to a method for machining a workpiece made of brittle material, in particular a substrate made of glass, glass ceramic, sapphire or silicon, wherein at least one filament-shaped hollow channel is formed in the volume of the workpiece, wherein the workpiece is irradiated with pulsed laser radiation which generates free electrons and / or ions from the material of the workpiece in the volume of the workpiece, so that a plasma with free electrons and / or ions is created in a filament-shaped volume region of the workpiece, which plasma leaves behind the filament-shaped hollow channel, and wherein the workpiece is subjected to an additional electric and / or magnetic field which acts on the free electrons and / or ions, in particular in order to influence the filament-shaped volume region and / or the filament-shaped hollow channel in the workpiece.

The invention relates to a method for producing a hollow structure (28) in a workpiece (25) in the form of a substrate for a mirror, in particular an EUV mirror (M4), by a material removal process with pulsed laser radiation (35), comprising the steps of irradiating the pulsed laser radiation (35) from a radiation inlet side (27) onto the workpiece (25) made of a material transparent to the pulsed laser radiation (35), focusing the pulsed laser radiation (35) in a focal region (39) and moving the focal region (39) along a movement pattern (41) to focus the workpiece (25). The method comprises the steps of forming a removal front (46) for areal removal of material of the workpiece (25) and manufacturing a hollow structure (28) by moving the removal front (46) in the workpiece (25), wherein the removal front (46) which is not aligned perpendicularly to the incident radiation direction (Z) of the pulsed laser radiation (35) at the radiation inlet side (27) of the workpiece (25) is formed at least intermittently during the manufacturing of the hollow structure (28), the hollow structure being manufactured in the form of a channel through which a fluid can flow. The invention also relates to a method for manufacturing a flow channel (28) in a workpiece (25) in the form of a substrate (25) for a mirror (M4), the flow channel (28) being manufactured by a material removal process by pulsed laser radiation (35), and wherein a fluid supply (50) is introduced at least partially into the flow channel (28) during the manufacturing of the flow channel (28). The invention also comprises an apparatus for carrying out the method, and a mirror, in particular an EUV mirror, an EUV lithography apparatus, a fluid supply apparatus and a fluid supply method.

It is an object of the invention to provide a method and a corresponding laser system that are simple and robust and that are able to provide sub-100 fs laser pulses using nonlinear frequency-conversion. The method of the invention comprises the steps of generating pulsed laser radiation at a fundamental wavelength, increasing the spectral bandwidth of the laser radiation by passing the laser radiation through a periodically poled nonlinear crystal material whose poling period is larger than or smaller than the poling period satisfying the quasi-phase-matching condition at the fundamental wavelength, and frequency-converting the spectrally broadened laser radiation. The laser system of the invention comprises a laser source generating pulsed laser radiation at a fundamental wavelength, a first periodically poled nonlinear crystal section arranged in the beam path and having a poling period larger than or smaller than the poling period satisfying the quasi-phase-matching condition at the fundamental wavelength to spectrally broaden the laser radiation, and a second periodically poled nonlinear crystal section arranged in the beam path downstream of the first section, wherein the second section is quasi-phase-matched at the fundamental wavelength to frequency-convert the laser radiation.

A laser system (1) comprises a laser radiation source (7) for providing a pulsed laser radiation (9), wherein the pulsed laser radiation comprises laser pulses (11) having a pulse energy in the range of 1 mJ to 100 J or in the range of 10 mJ to 1 J and a pulse duration in the range of 10 fs to 5 ps or in the range of 500 fs to 1.5 ps. The laser system (1) further comprises an optical system (3) for spectral broadening of the pulsed laser radiation (9). The optical system (3) comprises: - a first polarization setting optics (19) setting a circular polarization state (17B) of the pulsed laser radiation (9), and - a multi-pass cell (5) having at least two mirrors (25A, 25B) through which the pulsed laser radiation (9) passes forming a plurality of intermediate focus regions (29), wherein the multi-pass cell (5) is filled with a filling gas (5A) having an optical nonlinearity, wherein the filling gas (5A) enables spectral broadening of the pulsed laser radiation (9) in the intermediate focus regions (29). Further, a pressure of the filling gas (5A) is set in a pressure range in which there is an ionization behavior of the filling gas (5A) in the regime of multiphoton ionization, and a focus diameter (d) of the intermediate focus regions (29) is set such that the pulsed laser radiation (9) passes through the multi-pass cell (5) without ionization of the filling gas (5).

The present invention relates to a method and a device for shape correction of an optical component using pulsed laser radiation. For this purpose, the component is measured and excess material is determined by comparison with a target geometry. This excess material is then at least partially removed by processing with at least one pulsed laser beam with pulse durations of > 1 µs in order to at least approximate the actual geometry to the target geometry. During processing, the component is rotated at a speed about a rotational axis, with the distance of the laser beam from the rotational axis being changed at least temporarily. The speed, beam diameter of the laser beam on the component, and the temporal pulse spacing of the laser beam pulses are selected such that material regions of the component removed by successive pulses of the laser beam do not overlap.

A system for characterizing chiral molecules including an interaction zone arranged to receive a sample of chiral molecules; a laser source arranged to emit pulsed laser radiation, the laser radiation being suitable for interacting with the molecules in the interaction zone; a polarization modulator arranged to elliptically polarize the laser radiation; an optical cavity configured to redirect the pulsed laser radiation into the interaction zone several times; a detector arranged to measure a chiroptical signal produced by the interaction between the molecules and the laser radiation; and a determiner arranged and / or programmed to determine at least the chirality of the molecules from the detected chiroptical signal.

The invention relates to a method for producing a hollow structure (3) in a substrate (2), in particular a glass substrate, of a workpiece (1), wherein the hollow structure (3) to be produced has inner walls (4). The method comprises selecting a pulsed laser radiation (12) for which the material of the substrate (2) is at least partially transparent. Furthermore, the method comprises irradiating the pulsed laser radiation (12) into the substrate (2), focusing the pulsed laser radiation (12) in a focus area (15), and moving the focus area (15) along a desired geometry (17) of the hollow structure (3) to be produced. The pulsed laser radiation (12) modifies at least partially the material of the substrate (2) along the desired geometry (17) of the hollow structure (3) to be produced. Specifically, the pulsed laser radiation (12) modifies at least the material of the substrate (2) that borders the inner walls (4) of the hollow structure (3) to be produced.After the material has been modified by pulsed laser radiation (12), the modified material (2a) is thermally and / or mechanically processed in such a way that the material in the hollow structure (3) to be produced detaches from the substrate (2).

A device (11) for transmitting pulsed laser radiation having a pulse energy that results in a high-intensity laser pulse (3C) with a compressed pulse duration comprises a pulse duration setting device (13), a hollow-core fiber (1), and a fiber coupling input device (17). The pulse duration setting device is configured to receive the pulsed laser radiation and to set the transmission pulse duration (Δt_t) of the laser radiation. The hollow-core fiber has a hollow core (4A) surrounded by a material (4B), wherein the hollow-core fiber (1) transmits a laser pulse (3B) coupled into the first fiber end (1A) in the hollow core (4A) to a second fiber end (1B) and outputs the laser pulse at the second fiber end. The hollow-core fiber (1) is configured to operate with a beam trajectory parameter value (X, α) present at the first fiber end (1A), the beam trajectory parameter value being within a target tolerance range (ΔX_S). The fiber coupling device is configured to receive laser radiation set to the transmission pulse duration (Δt_t) and couple the laser radiation into the hollow core fiber (1) with a beam trajectory parameter value (X, α), the beam trajectory parameter value being within the target tolerance range (ΔX_S). The transmission pulse duration (Δt_t) is set in such a way that for all beam trajectory parameter values (X, α) within the target tolerance range (ΔX_S), the laser radiation is coupled into the hollow core (4A) in such a way that the material and / or structure (37) of the hollow core fiber (1) is retained during the coupling.

The invention relates to a method for manipulating pulsed laser radiation (2), having the following steps: - providing pulsed laser radiation (2); - spatially separating the frequency components of the pulsed laser radiation (2) to a first predetermined extent in a direction perpendicular to a propagation direction of the pulsed laser radiation (2); - guiding pulsed laser radiation (2), spatially separated to the first predetermined extent, to a multiple-pass gas cell (8); - increasing the spectral bandwidth of the pulsed laser radiation (2) in the multiple-pass gas cell (8) for temporal pulse compression of the pulsed laser radiation (2). The invention also relates to a corresponding device (1).

A system for material-ablative laser processing of workpieces in liquid is provided witha laser beam source for generating pulsed laser radiation;a focusing unit for focusing the laser radiation onto a workpiece;and a process chamber for receiving a workpiece. The process chamber includesa first side having a transparent process window for letting pass laser radiation;a second side arranged opposite the first side;a chamber wall surrounding an interior of the process chamber; anda flow generator for generating a flow within the interior of the process chamber. The flow generator includes a first flow generator unit for generating a first flow along a first flow axis and a second flow generator unit for generating a second flow along a second flow axis; anda positioning unit for adjusting the position of the laser radiation on the workpiece.

The invention relates to an optical system comprising a laser source (1) generating pulsed laser radiation consisting of a temporal sequence of laser pulses and at least one pulse compression device (3) located in the beam path and having a nonlinear medium (7), wherein the laser pulses undergo a nonlinear spectral broadening during the propagation through the medium (7) and a chirp is applied to the laser pulses. The object of the invention is to provide an optical system which makes it possible to generate nonlinearly compressed laser pulses with an improved temporal pulse contrast or with an improved pulse quality. According to the invention, a group delay dispersion which varies along the beam path and at least partially compensates the chirp is applied to the laser pulses by the pulse compression device (3).

The present invention relates to a surgical instrument for minimally invasive aspiration of tissue. A device for destroying cataracts in lens tissue. The device includes a housing; a pulsed laser radiation source and an optical waveguide. The optical waveguide is configured to conduct pulsed laser radiation from the pulsed laser radiation source and can be coupled to the pulsed laser radiation source at the proximal end of the optical waveguide to receive pulsed laser radiation from the pulsed laser radiation source. The device further includes a drive mechanism that is coupled to the optical waveguide to controllably change the relative position of the optical waveguide and the distal end of the housing.

Method for generating pulsed laser radiation, comprising the following process steps: - Generating first pulsed laser radiation, wherein the spectrum of the first pulsed laser radiation is an optical frequency comb with a number of equidistant spectral lines, - Generating a second pulsed laser radiation by frequency doubling of the first pulsed laser radiation, wherein the second pulsed laser radiation is polarized orthogonally to the first pulsed laser radiation, - Superposition of the individual pulses (3, 5) of the first and the second pulsed laser radiation to form a third pulsed laser radiation, - Detection of the polarization of the third pulsed laser radiation, - Deriving the temporal change of the carrier envelope phase of the individual pulses of the first pulsed laser radiation from the temporal evolution of the detected polarization.

The invention relates to a laser machining device (10), comprising - a laser beam source (12) for generating pulsed laser radiation (14); - a focusing unit (18) for focusing the laser radiation (14) onto a workpiece (22) to be machined; - a flow generator unit (24) for providing a flow on the surface of the workpiece (22), wherein the flow generator unit (24) has an inlet channel (26) and a flow generator for generating a flow and for providing a liquid (23) into the inlet channel (26); and - a holding unit (34) which is designed to receive the workpiece (22) to be machined, and wherein the holding unit (34) - has a first holding element (36) which is designed to receive a workpiece (22); - has a second holding element (38) which is designed to receive an annular fastening element (39), wherein the second holding element (38) annularly surrounds the first holding element (36); - a third holding element (40), which annularly surrounds the second holding element (38), wherein the third holding element (40) has a first end (42) which adjoins the second holding element (38) and has a second, distal end (44), and an outer region (46) which comprises the distal end (44), wherein the third holding element (40) has a greater height at its second end (44) than at its first end (42).

A pulse compressor (14) for time-compressing pulsed laser radiation according to a chirped pulse amplification, CPA, scheme, the pulse compressor comprising a first compressor element (14a), and a second compressor element (14b). The first compressor element (14a) is configured to receive as input the pulsed laser radiation and to produce as output first compressed radiation having a first pulse duration. The second compressor element (14b) is configured to receive as input the first compressed radiation and to produce as output second compressed radiation having a second pulse duration. The second pulse duration is shorter than the first pulse duration. The first compressor element (14a) is configured to time-compress the pulse of the pulsed laser radiation of a first compression factor. The second compressor element (14b) is configured to time-compress the pulse of the first compressed radiation of a second compression factor. The first compression factor is larger than the second compression factor.

The present invention relates to a method and a device for shape correction of an optical component using pulsed laser radiation. For this purpose, the component is measured, and excess material is determined by comparison with a target geometry. This excess material is then at least partially removed by processing with at least one pulsed laser beam with pulse durations of > 1 µs in order to approximate the actual geometry to the target geometry. During processing, the component is rotated about an axis of rotation at a certain speed, whereby the distance of the laser beam to the axis of rotation is changed at least temporarily. The rotational speed, the diameter of the laser beam on the component, and the temporal interval between the laser pulses are selected such that the material areas of the component removed by successive laser pulses do not overlap, as illustrated by way of example in Figure 3.

A laser system includes a laser radiation source for providing pulsed laser radiation, and an optical system that includes a first polarization setting optical unit configured to set a circular polarization state of the pulsed laser radiation and a multipass cell having at least two mirrors. The pulsed laser radiation passes through the multipass cell with formation of a plurality of intermediate focus zones. The multipass cell is filled with a filling gas that has an optical nonlinearity and causes a spectral broadening of the pulsed laser radiation in the intermediate focus zones. A pressure of the filling gas is set in a pressure range so that there is an ionization behavior of the filling gas in a form of multiphoton ionization. Focus diameters of the intermediate focus zones are set such that the pulsed laser radiation passes through the multipass cell without ionization of the filling gas.

The present invention relates to a method (100) for laser drilling or laser cutting of a workpiece (1), wherein material of the workpiece (1) is removed (110) by means of pulsed laser radiation (2), wherein a fluid (4) is arranged in a rear space (3) located behind a region (1a) to be penetrated of the workpiece (1) along the beam direction, wherein when the laser radiation has penetrated the region (1a), the laser radiation (2) enters the rear space, and the fluid at least partially blocks the passage of the laser radiation (2), wherein the fluid (4) comprises particles (4a) dispersed in a solvent (4b), and is characterized in that particles (4a) are selected (121) to form a plasma (5) under the action of the laser radiation (2) entering the rear space (3), so that the plasma (5) at least partially blocks the passage of the laser radiation (2).

Provided is an examination device comprising: a laser irradiation unit that irradiates an eye being examined with a pulsed laser beam; and a fluorescence detection unit that is provided with a detector for detecting autofluorescence which is from floating cells in the eye being examined and which occurs due to irradiation of the eye being examined with the pulsed laser beam, wherein the radiant exposure of the pulsed laser beam with which the floating cells in the eye being examined are irradiated is not more than 10 J / cm2. Also provided is a slit lamp microscope comprising the examination device.

The invention relates to a method for manufacturing a gemstone (10), in particular for timepieces, from a monocrystalline mineral body, the gemstone (10) comprising a hole (8). The method comprises an ablation step in which the body is subjected to material ablation by scanning at least one face of the body with ultrashort pulse laser radiation, the duration of which is less than one hundred picoseconds and whose beam is guided by a precession system of at least three axes configured to at least partially eliminate the conical focusing angle of the laser, the laser ablation step comprising the excavation of a cone (12) at the entrance to the hole (8). The invention also relates to a monocrystalline mineral gemstone, in particular for timepieces, the gemstone comprising a face (6) provided with a hole (8) formed in the body of the gemstone (10) and a functional element at the entrance to the hole (10). The functional element has the shape of a cone (12).

The invention relates to a device for generating a sequence of laser pulses consisting of pulse bursts. The object of the invention is to provide a possibility of generating laser pulses for material processing in the burst mode at a high quality based on the principle of beam combination. To that end, the invention proposes a device, comprising:at least one laser (1, 14, 15) which generates pulsed laser radiation in the form of a sequence of temporally equidistant individual pulses,a combination element (4) which superimposes the laser radiation supplied to the combination element (4) via at least two spatially separate input beam paths of different length, into pulse bursts in an output beam path (9),a coupling optics (10) arranged in the output beam path (9),an optical waveguide (11), wherein the coupling optics (10) couples the laser radiation superimposed in the output beam path (9) into the optical waveguide (11) at the input side thereof, and wherein the optical waveguide (11) guides the laser radiation primarily in a fundamental mode, anda decoupling optics (12) which couples out the laser radiation from the optical waveguide (11) at the output side thereof. Furthermore, the invention relates to a corresponding method.