Patent classifications
G02F1/354
BLUE LASER OPERATING AT THE H-BETA FRAUNHOFER LINE
The present invention provides a blue laser transmitter operating at the H-beta Fraunhofer line at 486.13 nm wavelength. The subject blue laser is based on pulsed lasing action in thulium doped into lutetium sesquioxide (Tm:Lu.sub.2O.sub.3). The laser wavelength is restricted by volume
Bragg grating to the vicinity of 1944 nm wavelength. The laser is operated with a q-switch to generate high-energy pulses within the nanosecond regime. The output at the 1944 nm wavelength is then frequency quadrupled in a single pass through non-linear crystals to a wavelength near the center of the H-beta Fraunhofer line. The operation at the 1944 nm wavelength in Tm:Lu.sub.2O.sub.3 is very efficient because this wavelength is located on a shoulder of a substantially broad emission peak at 1945 nm. In addition, at the 1944 nm wavelength, Tm:Lu.sub.2O.sub.3 has only a modest saturation fluence of about 15 J/cm.sup.2, which allows for efficient energy extraction.
Remote substance identification device and remote substance identification method
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.
Frequency conversion using interdigitated nonlinear crystal gratings
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.
GLASS PROCESSING METHOD
A glass processing method according to a viewpoint of the present disclosure includes generating a pulse laser beam by using a laser oscillator, and irradiating alkali-free glass to be processed with the pulse laser beam. The wavelength of the pulse laser beam ranges from 248 nm to 266 nm, and the pulse laser beam has an energy ratio greater than or equal to 91% but smaller than or equal to 99% in the region from 5 ns after a pulse rises to 400 ns.
TUNABLE DUV LASER ASSEMBLY
A tunable laser assembly uses a fundamental wavelength between 1 μm and 1.1 μm to alternately generate laser output light at two or more output wavelengths within the range of 184 nm to 200 nm by directing the fundamental light through different regions of a fan-out periodically poled nonlinear crystal to generate corresponding different down-converted signals, and using different nonlinear summing crystals to mix the different down-converted signals with a fifth harmonic of the fundamental wavelength. Each nonlinear summing crystal has a crystal axis aligned at an angle relative to the light propagation direction to facilitate the efficient transmission and summing of the fifth harmonic with an associated down-converted signal. In response to a user-selected output wavelength, a frequency control system positions the fan-out periodically poled nonlinear crystal to generate a corresponding down-converted signal frequency and positions an associated nonlinear summing crystal to receive the fifth harmonic and the corresponding down-converted signal.
METHOD AND APPARATUS FOR EFFICIENT HIGH HARMONIC GENERATION
A high harmonic radiation source and associated method of generating high harmonic radiation is disclosed. The high harmonic radiation source is configured to condition a gas medium by irradiating the gas medium with a pre-pulse of radiation, thereby generating a plasma comprising a pre-pulse plasma distribution; and irradiate the gas medium with a main pulse of radiation to generate said high harmonic radiation. The conditioning step is such that the plasma comprising a pre-pulse plasma distribution acts to configure a wavefront of said main pulse to improve one or both of: the efficiency of the high harmonic generation process and the beam quality of the high harmonic radiation. The high harmonic radiation source further may comprise a beam shaping device configured to shape said customized pre-pulse prior to said conditioning.
AN ILLUMINATION SOURCE AND ASSOCIATED METROLOGY APPARATUS
Disclosed is an illumination source comprising a gas delivery system comprising a gas nozzle. The gas nozzle comprises an opening in an exit plane of the gas nozzle. The gas delivery system is configured to provide a gas flow from the opening for generating an emitted radiation at an interaction region. The illumination source is configured to receive a pump radiation having a propagation direction and to provide the pump radiation in the gas flow. A geometry shape of the gas nozzle is adapted to shape a profile of the gas flow such that gas density of the gas flow first increases to a maximum value and subsequently falls sharply in a cut-off region along the propagation direction.
Method and system for generating intense, ultrashort pulses of XUV and soft x-ray radiation via HHG
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.
OPTICAL RESONATOR FREQUENCY COMB
An optical resonator frequency comb (1) comprising a main optical resonator (2) being made of a resonator material, which has a third order nonlinearity and an anomalous resonator dispersion; a continuous wave (cw) laser (4) configured for supplying continuous laser light into an optical waveguide (5), which is coupled with the main optical resonator. The cw laser (4), the optical waveguide (5) and the main optical resonator (2) are arranged for resonantly coupling the cw laser light into the main optical resonator (2) for forming a single dissipative soliton circulating in the main optical resonator (2) corresponding to the generation of a frequency comb. Furthermore, the optical resonator frequency comb further comprises an auxiliary optical element (3, 25, 26) configured to induce a phase shift to a frequency comb component at the cw laser frequency to enhance the conversion efficiency of a generated frequency comb. The disclosure also relates to an associated method.
Method for rapid growth of long seed KDP-type crystals
A pyramidal growth method for long-seed KDP-type crystal. In the growth method provided by the present invention, the lower end of the long-seed crystal is restricted by a lower tray, and the upper end is free to grow into a pyramidal. At the same time, the four prismatic faces at two directions of [100] and [010] can grow, avoiding growth stress problem during crystal growth, and all cut optical elements have high optical quality. Because the growth process is that four prismatic faces with highly similar growth environments grow at the same time and stirring is applied by blade-like stirring paddles during the crystal growth process, the cut optical elements have high optical uniformity.