Abstract: A device for generating laser pulses is provided, the device having an optical parametric oscillator converts the laser pulses of a pump laser to laser pulses at a signal wavelength and at an idler wavelength. The optical parametric oscillator has an optical resonator with a non-linear wavelength converter. It is an object of the invention to provide a device that makes efficient generation of synchronous laser pulse trains with two different central wavelengths possible. To this end, the invention proposes that the pump laser is tunable with respect to the pump wavelength and the repetition frequency, wherein the resonator has an optical fibre with a dispersion in the range of 10-100 ps/nm and a length of 10-1000 m. The invention furthermore relates to a method for generating laser pulses using such a device.

Abstract: The invention relates to an optical waveguide with two or more light-guiding cores (1a-1e) extending continuously along the longitudinal extension of the optical waveguide, parallel to one another and spaced apart from one another, from one end of the optical waveguide to the other, and with a first cladding (2) enclosing the cores (1a-1e). It is an object of the invention to provide a multicore optical waveguide for high-power operation with reduced system complexity compared to the prior art.

Abstract: The invention relates to a method for stably transmitting laser radiation through an optical waveguide (3), wherein two or more modes of the laser radiation propagating in the optical waveguide (3) interfere and form a mode interference pattern in the optical waveguide, as a result of which a thermally induced refractive index grating is produced in the optical waveguide (3). It is an object of the invention to demonstrate an effective approach for stabilizing the output signal of the optical waveguide (3) in a fiber-based laser/amplifier combination at high output powers, i.e. for avoiding mode instability. The invention achieves this object by virtue of the fact that a relative spatial phase shift between the mode interference pattern and the thermally induced refractive index grating is set in the direction of propagation of the laser radiation.

Abstract: An exemplary laser microscope can be provided, comprising at least one first laser source which emits at least one (e.g., pulsed) excitation beam, a scanning optical configuration (e.g., configured to scan the excitation beam over the surface of a sample), a focusing optical configuration (e.g., configured to focus the excitation beam onto the sample), and at least one detector configured to detect light emitted by the sample due to an optical effect in response to the excitation beam. A second laser source facilitates a pulsed ablation beam for a local ablation of the material of the sample. The ablation beam can be guided to the sample via the scanning and focusing optical configurations. The first and second laser sources can be fed by a mutual continuous wave pump laser and/or a mutual pulsed pump laser. The first laser source can emit pulses with at least two different wavelengths.

Abstract: The invention relates to an apparatus for generating laser pulses. It is an object of the invention to provide a method for generating synchronized laser pulse trains at variable wavelengths (e.g., for coherent Raman spectroscopy/microscopy), wherein the switching time for switching between different wavelengths should be in the sub-?s range. For this purpose the apparatus according to the invention comprises a pump laser (1), which emits pulsed laser radiation at a specified wavelength, an FDML laser (3), which emits continuous wave laser radiation at a cyclically variable wavelength, and a nonlinear conversion medium (4), in which the pulsed laser radiation of the pump laser (1) and the continuous wave laser radiation of the FDML laser (3) are superposed.

Abstract: An exemplary laser microscope can be provided, comprising at least one first laser source which emits at least one (e.g., pulsed) excitation beam, a scanning optical configuration (e.g., configured to scan the excitation beam over the surface of a sample), a focusing optical configuration (e.g., configured to focus the excitation beam onto the sample), and at least one detector configured to detect light emitted by the sample due to an optical effect in response to the excitation beam. A second laser source facilitates a pulsed ablation beam for a local ablation of the material of the sample. The ablation beam can be guided to the sample via the scanning and focusing optical configurations, The first and second laser sources can be fed by a mutual continuous wave pump laser- and/or a mutual pulsed pump laser. The first laser source can emit pulses with at least two different wavelengths.

Abstract: The invention relates to a device (1) for generating laser pulses, comprising a pump laser (1), which emits laser pulses at a pump wavelength (12) with a repetition frequency, wherein the pulse duration of the laser pulses is 0.5-100 ps, and an optical parametric oscillator (3) that converts the laser pulses of the pump laser (1) at least partially to laser pulses at a signal wavelength (10) and at an idler wavelength (11), which differs from the former, wherein the optical parametric oscillator (3) has an optical resonator (20), comprising a non-linear wavelength converter (22), which converts the laser pulses of the pump laser (1) to laser pulses at the signal wavelength (10) and at the idler wavelength (11), and an output coupling element (24), which couples at least some of the radiation out of the optical resonator (20).

Abstract: The invention relates to an optical arrangement having a division element which divides an input beam consisting of a sequence of temporally equidistant light pulses into two spatially separate partial beams, at least one optical element through which at least one of the partial beams propagates, and at least one combination element which spatially superimposes the partial beams in an output beam. It is the object of the present invention to show a method for increasing the pulse energy of light pulses which is improved in comparison with the prior art. The invention solves this problem by virtue of the fact that the combination element superimposes a number of the temporally successive light pulses in a single light pulse in the output beam. The invention also relates to a method for increasing the pulse energy of light pulses.

Abstract: The invention relates to an apparatus for generating laser pulses. It is an object of the invention to provide a method for generating synchronized laser pulse trains at variable wavelengths (e.g., for coherent Raman spectroscopy/microscopy), wherein the switching time for switching between different wavelengths should be in the sub-?s range. For this purpose the apparatus according to the invention comprises a pump laser (1), which emits pulsed laser radiation at a specified wavelength, an FDML laser (3), which emits continuous wave laser radiation at a cyclically variable wavelength, and a nonlinear conversion medium (4), in which the pulsed laser radiation of the pump laser (1) and the continuous wave laser radiation of the FDML laser (3) are superposed.

Abstract: A method for generating a laser pulse train is provided, including at least the following method steps: generating a laser pulse train at a pulse repetition frequency; coupling the laser pulse train into an acousto-optical modulator, and selecting individual laser pulses of the laser pulse train. A system for generating a laser pulse train is also provided, including at least a pulsed laser and an acousto-optical modulator, and an associated control device.

Abstract: The invention relates to a method for stably transmitting laser radiation through an optical waveguide (3), wherein two or more modes of the laser radiation propagating in the optical waveguide (3) interfere and form a mode interference pattern in the optical waveguide, as a result of which a thermally induced refractive index grating is produced in the optical waveguide (3). It is an object of the invention to demonstrate an effective approach for stabilizing the output signal of the optical waveguide (3) in a fiber-based laser/amplifier combination at high output powers, i.e. for avoiding mode instability. The invention achieves this object by virtue of the fact that a relative spatial phase shift between the mode interference pattern and the thermally induced refractive index grating is set in the direction of propagation of the laser radiation.

Abstract: A method of propagating a laser signal through an optical waveguide and a waveguide laser system provide a novel way of stabilizing the beam emitted by a fiber laser system above the mode instability threshold wherein the beat length of two or more interfering transverse modes of the laser signal in the optical waveguide is modulated in time.

Abstract: The invention relates to an optical waveguide (3) as a laser medium or as a gain medium for high-power operation, wherein the optical waveguide (3) is an optical fiber, the light-guiding core of which, at least in sections, is doped with rare earth ions. It is an object of the invention to provide an optical waveguide as a laser or a gain medium, and a laser/amplifier combination realized therewith, in which the output signal of the laser or gain medium is better stabilized. The invention achieves this object by virtue of the maximum small signal gain of the optical waveguide (1) being up to 60 dB, preferably up to 50 dB, more preferably up to 40 dB, even more preferably up to 30 dB, on account of the concentration of the rare earth ions and/or the distribution thereof in the light-guiding core. Moreover, the invention relates to the use of such an optical waveguide as an amplifier fiber (3) in a laser/amplifier combination.

Abstract: The invention relates to an optical waveguide with at least one core region (1) extending along the longitudinal extent of the optical waveguide, and with a first jacket (2) which, viewed in the cross section of the optical waveguide, surrounds the core region (1). The invention further relates to an optical arrangement with such an optical waveguide, and to a method for producing the optical waveguide. The object of the invention is to make available an optical waveguide for high-performance operation, which is improved in relation to the prior art in terms of mode instability. The invention achieves this object by virtue of the fact that the optical waveguide consists of crystalline material at least in the core region (1).

Abstract: The invention relates to an optical arrangement having a division element which divides an input beam consisting of a sequence of temporally equidistant light pulses into two spatially separate partial beams, at least one optical element through which at least one of the partial beams propagates, and at least one combination element which spatially superimposes the partial beams in an output beam. It is the object of the present invention to show a method for increasing the pulse energy of light pulses which is improved in comparison with the prior art. The invention solves this problem by virtue of the fact that the combination element superimposes a number of the temporally successive light pulses in a single light pulse in the output beam. The invention also relates to a method for increasing the pulse energy of light pulses.

Abstract: The invention relates to an optical array comprising a splitting element (1) which splits an input beam (E) into at least two partial beams (T1, T2, T3, T4), at least one optical element (V1, V2, V3, V4, MV) through which at least one of the partial beams (T1, T2, T3, T4) propagates, and at least one combining element (4) which spatially superimposes the partial beams (T1, T2, T3, T4) in one output beam (A). The object of the invention is to provide an optical array which is improved over the prior art and which permits effective and simple splitting of the input light beam, in particular a laser beam with pulsed or continuous emission. The invention achieves this object in that the splitting element (1) and/or the combining element (4) each have a partially reflective element (2, 2?) which reflects the radiation of the input beam (E) or of the output beam (A) two or more times, wherein the partially reflective element (2, 2?) has zones (a, b, c, d) of different reflectivity.

Abstract: The invention relates to a method for generating a laser pulse train, comprising the following method steps: generating the laser pulse train (4a) at a pulse repetition frequency; coupling the laser pulse train (4a) into an acousto-optical modulator, and selecting individual laser pulses of the laser pulse train (4a) by driving the acousto-optical modulator with high-frequency pulses (4h), wherein the high-frequency pulses (4h) are generated by modulating a high-frequency carrier signal (4f) with a periodic switching signal (4e). In addition, the invention relates to a system for generating a laser pulse train, comprising a pulsed laser (1), which generates the laser pulse train at a pulse repetition frequency, and an acousto-optical modulator (2), in which the laser pulses propagate, and comprising a control device (7), which drives the acousto-optical modulator (2) with high-frequency pulses for the purpose of selecting individual laser pulses.

Abstract: The invention relates to an optical waveguide (3) as a laser medium or as a gain medium for high-power operation, wherein the optical waveguide (3) is an optical fiber, the light-guiding core of which, at least in sections, is doped with rare earth ions. It is an object of the invention to provide an optical waveguide as a laser or a gain medium, and a laser/amplifier combination realized therewith, in which the output signal of the laser or gain medium is better stabilized. The invention achieves this object by virtue of the maximum small signal gain of the optical waveguide (1) being up to 60 dB, preferably up to 50 dB, more preferably up to 40 dB, even more preferably up to 30 dB, on account of the concentration of the rare earth ions and/or the distribution thereof in the light-guiding core. Moreover, the invention relates to the use of such an optical waveguide as an amplifier fiber (3) in a laser/amplifier combination.

Abstract: The invention relates to an apparatus (1) for producing short synchronous radiation pulses at different wavelengths, particularly to an optically parametric oscillator, comprising at least one pump radiation source (2), preferably a pump laser, for outputting radiation at a pump wavelength, and a resonator (3) having a wavelength-dependent effective resonator length, wherein the resonator (3) has a non-linear wavelength converter (4) for producing radiation at a first and a second wavelength; a dispersive element (5) having a strong wavelength-dependent delay characteristic; and a coupling-out element (6) for at least partially coupling-out the radiation from the resonator (3). In addition, the invention relates to a method for producing short radiation pulses by means of an apparatus (1), particularly an optically parametric oscillator.

Abstract: A method of propagating a laser signal through an optical waveguide and a waveguide laser system provide a novel way of stabilizing the beam emitted by a fiber laser system above the mode instability threshold wherein the beat length of two or more interfering transverse modes of the laser signal in the optical waveguide is modulated in time.