A semiconductor laser light-emitting structure includes a semiconductor laser light-emitting structure having a vertical-cavity surface-emitting laser structure and configured to emit light having a first wavelength, and a wavelength converter including a metasurface and monolithically formed with the semiconductor laser light-emitting structure on a light output side of the semiconductor laser light-emitting structure, wherein the metasurface is configured to non-linearly convert the light having the first wavelength into light having a second wavelength.

A collinear T-cavity VECSEL system generating intracavity Hermite-Gaussian modes at multiple wavelengths, configured to vary each of these wavelengths individually and independently. A mode converter element and/or an astigmatic mode converter is/are aligned intracavity to reversibly convert the Gaussian modes to HG modes to Laguerre-Gaussian modes, the latter forming the system output having any of the wavelengths provided by the spectrum resulting from nonlinear frequency-mixing intracavity (including generation of UV, visible, mid-IR light). The laser system delivers Watt-level output power in tunable high-order transverse mode distribution.

A visible light source includes a substrate, a vertical-cavity surface-emitting laser including an active semiconductor region configured to emit infrared light and a first reflector configured to reflect the infrared light emitted by the active semiconductor region, a second reflector configured to reflect the infrared light and form a vertical cavity for the infrared light with the first reflector, and one or more micro-resonators configured to receive the infrared light and generate visible light in one or more colors using the infrared light through optical parametric oscillation. The visible light source also includes one or more output couplers configured to couple the visible light in one or more colors from the one or more micro-resonators into free space or into a photonic integrated circuit.

A narrow linewidth mid infrared laser, including a pumping laser diode with a fast-axis compressor and a pumping wavelength λ.sub.o; and an optical resonator arranged to receive the pumping wavelength λ.sub.o, the optical resonator including a laser crystal with a lasing wavelength λ.sub.p, a dichroic mirror, and a nonlinear crystal to generate an idler wavelength λ.sub.i.

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 system for resonantly enhanced frequency conversion includes a nonlinear crystal for frequency converting a pump laser beam, and mirrors forming a ring resonator for the pump laser beam such that a closed propagation path of the pump laser beam, inside the ring resonator, passes through the nonlinear crystal. The mirrors include an adaptive mirror, a curved-mirror pair positioned in a first segment of the propagation path spanning between the adaptive mirror and the nonlinear crystal, and an input coupler for coupling the pump laser beam into the ring resonator. The curved-mirror pair forms an imaging system having conjugate planes at the adaptive mirror and the nonlinear crystal. The input coupler is positioned in a second segment of the propagation path that spans between the adaptive mirror and the nonlinear crystal and does not include deflection by the curved-mirror pair.

A current control device supplies a current to a semiconductor laser in order to output laser light to the semiconductor laser, and includes a current commander and a supplier. The current commander outputs a command value corresponding to a current value by increasing the command value with a lapse of time until reaching a target command value corresponding to a current value for outputting the laser light with a predetermined strength. The supplier supplies a current with a size corresponding to the command value output by the current commander to the semiconductor laser.

A chip scale ultra violet laser source includes a plurality of laser elements on a substrate each including a back cavity mirror, a tapered gain medium, an outcoupler, a nonlinear crystal coupled to the outcoupler with a front facet that has a first coating that is anti-reflectivity (AR) to a fundamental wavelength of the laser element and high reflectivity (HR) to ultra violet wavelengths, and has an exit facet that has a second coating that has HR to a fundamental wavelength of the laser element and AR to the ultra violet wavelengths, a photodetector coupled to the outcoupler, a phase modulator coupled to the photodetector and coupled to the back cavity mirror, and a master laser diode on the substrate coupled to the phase modulator of each laser element. Each laser element emits an ultra violet beamlet and is frequency and phase locked to the master laser diode.

A Schottky diode is monolithically integrated into the core of an infrared semiconductor laser (e.g., a quantum cascade laser) to create a heterodyned infrared transceiver. The internal mode field of the infrared semiconductor laser couples to an embedded Schottky diode and can mix the infrared fields to generate a response at the difference frequency.

A laser assembly for generating laser output light at an output wavelength of approximately 183 nm includes a fundamental laser, an optical parametric system (OPS), a fifth harmonic generator, and a frequency mixing module. The fundamental laser generates fundamental light at a fundamental frequency. The OPS generates a down-converted signal at a down-converted frequency. The fifth harmonic generator generates a fifth harmonic of the fundamental light. The frequency mixing module mixes the down-converted signal and the fifth harmonic to produce the laser output light at a frequency equal to a sum of the fifth harmonic frequency and the down-converted frequency. The OPS generates the down-converted signal by generating a down-converted seed signal at the down-converted frequency, and then mixing the down-converted seed signal with a portion of the fundamental light. At least one of the frequency mixing, frequency conversion or harmonic generation utilizes an annealed, deuterium-treated or hydrogen-treated CLBO crystal.