An electrodeless laser-driven light source includes a laser that generates a CW sustaining light. A pump laser generates pump light. A Q-switched laser crystal receives the pump light generated by the pump laser and generates pulsed laser light at an output in response to the generated pump light. A first optical element projects the pulsed laser light along a first axis to a breakdown region in a gas-filled bulb comprising an ionizing gas. A second optical element projects the CW sustaining light along a second axis to a CW plasma region in the gas-filled bulb comprising the ionizing gas. A detector detects plasma light generated by a CW plasma and generates a detection signal at an output. A controller generates control signals that control the pump light to the Q-switched laser crystal so as to extinguish the pulsed laser light within a time delay after the detection signal exceeds a threshold level.

A method for generating femtosecond vortex beams with high spatial intensity contrast, where a noncollinearly pumped HG beam femtosecond laser generates femtosecond HG beam and a cylindrical lens mode converter converts the femtosecond HG beam to femtosecond LG vortex beam. The HG beam femtosecond laser comprises a pump source, a gain medium, a saturable absorption mirror as mode-locker, and an output coupler with a noncollinear angle between the laser beam and the pump beam in the gain medium, which enables the laser to generate pure, order-tunable femtosecond HG beams. Femtosecond vortex beams obtained after the cylindrical lens converter have high-intensity-contrast, and are topological charge-tunable.

Compact optical frequency sources are described. The comb source may include an intra-cavity optical element having a multi-material integrated structure with an electrically controllable active region. The active region may comprise a thin film. By way of example, the thin film and an insulating dielectric material disposed between two electrodes can provide for rapid loss modulation. In some embodiments the thin film may comprise graphene. In various embodiments of a frequency comb laser, rapid modulation of the CEO frequency can be implemented via electric modulation of the transmission or reflection loss of an additional optical element, which can be the saturable absorber itself. In another embodiment, the thin film can also be used as a saturable absorber in order to facilitate passive modelocking. In some implementations the optical element may be formed on a cleaved or polished end of an optical fiber.

An optoelectronic oscillator for generating an optical and/or electric pulse comb, comprising a monolithically integrated passively mode-coupled semiconductor laser and an optical feedback loop which guides a part of the optical radiation of the semiconductor laser and feeds said part back into the semiconductor laser as feedback pulses. Without the influence of the feedback pulses, the semiconductor laser would emit comb-like optical pulses, hereafter referred to as primary pulses, and in the event of an influence, emits comb-like output pulses which have been influenced by the feedback pulses, said output pulses having a lower temporal jitter or less phase noise than the primary pulses. The feedback loop is damped between 27.5 and 37.5 dB, and the time lag of the feedback loop is selected such that each feedback pulse is incident within the temporal half-value width of each subsequent primary pulse.

A light source unit, a light source module, and a laser ignition device. The light source unit includes a lens array including a plurality of two-dimensionally disposed lenses and a lens substrate portion that supports the lenses, and an element substrate portion that supports a plurality of light emitters. The element substrate portion has a second coefficient of linear expansion. The first coefficient of linear expansion is approximately same as the second coefficient of linear expansion of the element substrate portion. The light source module includes the light source unit, and a condenser lens to collect and condense pump light emitted from the light source unit. The laser ignition device includes the light source module, and a laser resonator to absorb the pump light emitted from the light source unit.

A MOPA laser system that includes a seed laser configured to output pulsed laser light, an amplifier configured to receive and amplify the pulsed laser light emitted by the seed laser; and a pump laser configured to deliver a pump laser beam to both the seed laser and the amplifier.

Examples of robust self-starting passively mode locked fiber oscillators are described. In certain implementations, the oscillators are configured as Fabry-Perot cavities containing an optical loop mirror on one cavity end and a bulk mirror or saturable absorber on the other end. The loop mirror can be further configured with an adjustable line phase delay to optimize modelocking. All intra-cavity fiber(s) can be polarization maintaining. Dispersion compensation components such as, e.g., dispersion compensation fibers, bulk diffraction gratings or fiber Bragg gratings may be included. The oscillators may include a bandpass filter to obtain high pulse energies when operating in the similariton regime. The oscillator output can be amplified and used whenever high power short pulses are required. For example the oscillators can be configured as frequency comb sources or supercontinuum sources. In conjunction with repetition rate modulation, applications include dual scanning delay lines and trace gas detection.

A modular, compact and widely tunable laser system for the efficient generation of high peak and high average power ultrashort pulses. Peak power handling capability of fiber amplifiers is expanded by using optimized pulse shapes, as well as dispersively broadened pulses. Dispersive pulse stretching in the presence of self-phase modulation and gain results in the formation of high-power parabolic pulses. To ensure a wide tunability of the whole system, Raman-shifting of the compact sources of ultrashort pulses in conjunction with frequency-conversion in nonlinear optical crystals can be implemented, or an Anti-Stokes fiber in conjunction with fiber amplifiers and Raman-shifters are used. Positive dispersion optical amplifiers are used to improve transmission characteristics. An optical communication system utilizes a Raman amplifier fiber pumped by a train of Raman-shifted, wavelength-tunable pump pulses, to thereby amplify an optical signal which counterpropagates within the Raman amplifier fiber with respect to the pump pulses.

A frequency comb laser providing large comb spacing is disclosed. At least one embodiment includes a mode locked waveguide laser system. The mode locked waveguide laser includes a laser cavity having a waveguide, and a dispersion control unit (DCU) in the cavity. The DCU imparts an angular dispersion, group-velocity dispersion (GVD) and a spatial chirp to a beam propagating in the cavity. The DCU is capable of producing net GVD in a range from a positive value to a negative value. In some embodiments a tunable fiber frequency comb system configured as an optical frequency synthesizer is provided. In at least one embodiment a low phase noise micro-wave source may be implemented with a fiber comb laser having a comb spacing greater than about 1 GHz. The laser system is suitable for mass-producible fiber comb sources with large comb spacing and low noise. Applications include high-resolution spectroscopy.

A method and apparatus for characterizing an optical element. The optical element is part of a laser and is mounted on a translation stage to scan the optical element transverse to an intracavity laser beam. A performance characteristic of the laser is recorded as a function of position of the optical element.