The present invention describes a laser system for eliminating astigmatism to produce an elliptical laser beam that has an ellipticity between about 0.9 to 1.0. The laser system described herein allows for increased conversion efficiency and output powers. on-linear optical elements in the laser system eliminate astigmatism. The laser system comprises one or more cavities with wavelength splitters that act as dual-minor chambers for single-pass light transmission through the non-linear optical elements to reduce cavity size or as beam splitters for double-pass light transmission through the non-linear optical elements to increase laser output power. The laser system may also include a birefringent filter and/or etalon in the first cavity for polarization and wavelength tuning. The laser system may also generate a high-power, deep-ultraviolet laser output. The laser system may also be devoid of curved mirrors and non-normal incidence reflection to eliminate astigmatism.

A high harmonic generation assembly and method for generating high harmonic radiation. The assembly comprises a cavity configured to receive input radiation and increase the intensity of the input radiation inside the cavity for forming drive radiation suitable for use in high harmonic generation. The assembly further comprises an interaction region within the cavity at which, in use, a medium is present, the medium being configured to generate harmonic radiation by high harmonic generation when the drive radiation is incident thereupon, and an optical assembly configured to direct the drive radiation to pass through the interaction region, and comprising an output coupler comprising an aperture through which at least a part of the generated harmonic radiation is able to exit the cavity. The optical assembly is further configured to shape the drive radiation into a converging hollow beam before the drive radiation passes through the interaction region.

An optical resonator frequency comb comprising a main optical resonator being made of a resonator material, which has a third order nonlinearity and an anomalous resonator dispersion; a continuous wave (cw) laser configured for supplying continuous laser light into an optical waveguide, which is coupled with the main optical resonator. The cw laser, the optical waveguide and the main optical resonator are arranged for resonantly coupling the cw laser light into the main optical resonator for forming a single dissipative soliton circulating in the main optical resonator corresponding to the generation of a frequency comb. Furthermore, the optical resonator frequency comb further comprises an auxiliary optical element 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.

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.

This application provides a light source system and a laser projection display device. The light source system and the laser projection display device are applied to the field of laser projection display. The light source system includes an infrared laser light source and a nonlinear optical crystal array. An input end of the nonlinear optical crystal array is connected to an output end of the infrared laser light source, the nonlinear optical crystal array is configured to: perform frequency conversion on an infrared laser generated by the infrared laser light source, and output a laser obtained after the frequency conversion, the infrared laser light source is a pump light source, the nonlinear optical crystal array includes at least one nonlinear optical crystal.

The invention relates to a frequency conversion arrangement (100) for optimising properties of a harmonic of a laser, in particular a beam profile and/or a long-term stability, the arrangement comprising:—a first non-linear crystal (X1), which is designed to convert a first wavelength (λ1) partially into a second wavelength (λ2); and—an optical unit, which in particular comprises at least one prism (P), which is designed in such a way as to influence the main axes (x1, y1, x2, y2) of the beam profiles of the first wavelength (λ1) and/or the second wavelength (λ2) differently; and—a second non-linear crystal (X2), which is designed in such a way as to generate a third wavelength (λ3) from the unconverted part of the first wavelength (λ1) and/or the second wavelength (λ2), the second non-linear crystal (X2) having an entry face (A1) and an exit face (A2), and the exit face (A2) running obliquely to the entry face (A1).

Described embodiments include a plasmonic apparatus and method. The plasmonic apparatus includes a substrate having a first negative-permittivity layer comprising a first plasmonic surface. The plasmonic apparatus includes a plasmonic nanoparticle having a base with a second negative-permittivity layer comprising a second plasmonic surface. The plasmonic apparatus includes a dielectric-filled gap between the first plasmonic surface and the second plasmonic surface. The plasmonic apparatus includes a plasmonic cavity created by an assembly of the first plasmonic surface, the second plasmonic surface, and the dielectric-filled gap, and having a spectrally separated first fundamental resonant cavity wavelength λ.sub.1 and second fundamental resonant cavity wavelength λ.sub.2. The plasmonic apparatus includes a plurality of fluorescent particles located in the dielectric-filled gap. Each fluorescent particle of the plurality of fluorescent particles having an absorption spectrum including the first fundamental resonant cavity wavelength λ.sub.1 and an emission spectrum including the second fundamental resonant cavity wavelength λ.sub.2.

A method and apparatus for generating high-order harmonics in a solid-state medium comprising integrated semiconductor devices and electronics. The high-order harmonics interact with and are modified by the internal electric field associated with the operation of the integrated semiconductor devices and electronics. Measurement of the high-order harmonics after modification by the internal electric fields amounts to high resolution (temporal and spatial) dynamic imaging of the internal electric fields associated with the integrated semiconductor devices and electronics.

A nonlinear crystal including stacked strontium tetraborate SrB.sub.4O.sub.7 (SBO) crystal plates that are cooperatively configured to create a periodic structure for quasi-phase-matching (QPM) is used in the final frequency doubling stage of a laser assembly to generate laser output light having a wavelength in the range of about 180 nm to 200 nm. One or more fundamental laser beams are frequency doubled, down-converted and/or summed using one or more frequency conversion stages to generate an intermediate frequency light with a corresponding wavelength in the range of about 360 nm to 400 nm, and then the final frequency converting stage utilizes the nonlinear crystal to double the frequency of the intermediate frequency light to generate the desired laser output light at high power. Methods, inspection systems, lithography systems and cutting systems incorporating the laser assembly are also described.