An apparatus for spectral broadening of laser pulses includes a main body, a plurality of mirror elements fastened to the main body, each having a mirror surface formed thereon and configured to reflect the laser pulses the plurality of mirror elements being fastened to a main body, and at least one nonlinear optical medium for the passage of the laser pulses for the generation of a nonlinear phase (Φ.sub.NL) by self-phase modulation. The at least one nonlinear optical medium may be a sheet-like and disk-shaped solid-state optical medium and/or a gaseous optical medium.

Object: To provide a remote substance identification device that can identify an unidentified substance, such as a harmful substance, from a remote location. Solution: Provided are a remote substance identification device and method, the device comprising a laser device 10 that emits a laser beam to an irradiated space; a wavelength conversion device 20 that converts a wavelength of the laser beam emitted from the laser device into a plurality of different wavelengths and that emits laser beams of the different wavelengths to the irradiated space; a light collecting-detecting device 30, 40, 50 that collects and detects resonance Raman-scattered light generated from an irradiated object due to resonance Raman scattering; and a processor 60 that identifies the irradiated object on the basis of a result detected by the collecting-detecting device 30, 40, 50.

The concentration of substance in blood is measured non-invasively, with high accuracy and with simple configuration. Laser light 100 generated by a light source 10 is locally irradiated on the body epithelium F of a subject, and the resulting diffused reflected light 200 is detected by a light detector 40. The laser light 100 has a wavelength of 9.26 μm. The laser light 100 is generated by converting and amplifying pulsed excitation light 101 from an excitation light source 11 to a long wavelength. A plate-shaped window 300 that is transparent to mid-infrared light is brought in close contact with the body epithelium F. The glucose concentration in interstitial fluid can be calculated using normalized light intensity calculated from a signal ratio of signals from a monitoring light detector 16 and light detector 40.

A nonlinear crystal grating assembly including two integral nonlinear crystal grating structures having inverted crystal axes and having parallel spaced-apart mesas with predetermined mesa widths arranged such that, when assembled in an interdigitated configuration, the mesas of the two grating structures form an alternating grating pattern that is aligned with a propagation direction of input light, thereby creating a periodic structure for quasi-phase-matching (QPM). The nonlinear crystal grating structures are formed using strontium tetraborate, lithium triborate or another nonlinear crystal material. The nonlinear crystal grating assembly is utilized in a laser assembly in which fundamental wavelengths are doubled and/or summed using intermediate frequency conversion stages, and then a final frequency converting stage utilizes the nonlinear crystal grating assembly to double or sum one or more intermediate light beam frequencies to generate laser output light at high power and photon energy levels. A method and inspection system are also described.

A method for providing a detection-signal for objects to be detected—at least a first and second light-beam including different frequencies being generated with a first optical non-linear 3-wave-process from a light-beam of a light-source including an output-frequency, and the first light-beam including a reference-frequency being detected, and the second light-beam including an object-frequency being emitted and received after reflection on an object, and the light-beam including the output-frequency and the second light-beam including the object-frequency being superposed, and a reference-beam including a reference-frequency being generated with a second optical non-linear 3-wave-process from the two superposed light-beams including the output-frequency and including the object-frequency, and a detection-signal being generated so that the object-distance is determinable due to the aforementioned superposition based on the time-difference between the detection of the first light-beam including the reference-frequency and a detection of a change of the reference-beam including the reference-frequency.

A nonlinear converter may comprise: alternating layers of a dielectric material and a metal material; a first refractive index of the nonlinear converter for a first wavelength (i.e., input wavelength or pump wavelength) between 207 nm and 237 nm, the first refractive index being less than 0.5, the first refractive index corresponding to metal fill ratio; and a second refractive index of the nonlinear converter for a second wavelength (i.e., output wavelength or SHG wavelength), the second wavelength being approximately double the first wavelength, the second refractive index corresponding to the metal fill ratio.

A method and a system for generating intense, ultrashort pulses of XUV and soft X-ray radiation via high-order harmonic generation (HHG), the method comprising selecting a nonlinear solid target and a laser source; separating a beam from the laser source into a first laser beam and a second laser beam; focusing the first laser beam onto the nonlinear solid target, thereby generating a laser ablated plume; and compressing and frequency-doubling the second laser beam and directing a resulting second compressed and frequency-doubled laser beam to the laser ablated plume, thereby yielding high-order harmonic generation of radiation of photon energies in a range between 12 eV and 36 eV. A high-order harmonic source of radiation, comprising a nonlinear solid target; a laser source; a beam splitter separating a beam from the laser source into a first beam line and a second beam line; the first beam line comprising a first focusing unit directing a first, uncompressed, laser beam onto the nonlinear solid target, to generate a laser ablated plume; and the second beam line directing a second, compressed and frequency-doubled laser beam, to the laser ablated plume, yielding high-order harmonic generation of radiation of photon energies in a range between 12 eV and 36 eV.

A wavelength conversion device that includes a plurality of crystal layers adjacent to one another such that crystal-axis orientations thereof are alternately arranged, the plurality of crystal layers each including a first-thickness portion having a first thickness and a second-thickness portion having a second thickness smaller than the first thickness; and an adhesive layer in at least part of a gap between adjacent second-thickness portions of the plurality of crystal layers and with which the plurality of crystal layers are bonded to one another.

A frequency conversion laser system is configured with a single mode (SM) laser source outputting a pulsed pump beam at a fundamental frequency and a nonlinear optical system operating to convert the fundamental frequency sequentially to a second harmonic (SH) and then third harmonic (TH). The nonlinear optical system includes an elongated SHG crystal traversed by the SM pulsed pump beam which generates the SH beam. The SHG crystal has an output surface inclined relative to a longitudinal axis of the SHG crystal at a first wedge angle different from a right angle. The nonlinear optical system further has an elongated THG crystal with an input surface which is impinged upon by a remainder of the pump and SHG beams which propagate through the THG crystal at a walk-off angle therebetween to generate a third harmonic (TH) beam, the input surface of the THG crystal being inclined to a longitudinal axis of the THG crystal at a second wedge angle. The output and input surfaces of respective SHG and THG crystals are inclined so as to minimize the walk-off angle between SH and IR pointing vectors in the THG crystal thereby improving the conversion efficiency and TH output beam's ellipticity.

A nonlinear crystal grating assembly including two integral nonlinear crystal grating structures having inverted crystal axes and having parallel spaced-apart mesas with predetermined mesa widths arranged such that, when assembled in an interdigitated configuration, the mesas of the two grating structures form an alternating grating pattern that is aligned with a propagation direction of input light, thereby creating a periodic structure for quasi-phase-matching (QPM). The nonlinear crystal grating structures are formed using strontium tetraborate, lithium triborate or another nonlinear crystal material. The nonlinear crystal grating assembly is utilized in a laser assembly in which fundamental wavelengths are doubled and/or summed using intermediate frequency conversion stages, and then a final frequency converting stage utilizes the nonlinear crystal grating assembly to double or sum one or more intermediate light beam frequencies to generate laser output light at high power and photon energy levels. A method and inspection system are also described.