An example laser apparatus of the disclosure may include an oscillator capable of outputting a laser beam, a slab optical amplifier capable of amplifying the laser beam outputted by the oscillator by passing the laser beam through an optical amplification region shaped like a slab and outputting the amplified laser beam, and a mirror disposed on an optical path of the laser beam to enter the slab optical amplifier or the amplified laser beam outputted from the slab optical amplifier, the mirror being movable in a direction parallel to a plane where the laser beam travels in the slab optical amplifier.

A method of calibrating a tunable laser includes shifting a filter output peak defined by a tunable optical feedback filter of the tunable laser in an optical spectral domain to align with a target etalon output peak of a plurality of spaced etalon output peaks defined by an etalon of the tunable laser. The method also includes shifting a cavity frequency grid defined by cavity modes of the tunable laser to align a target cavity mode of the cavity frequency grid with the filter output peak and shifting the spaced output peaks defined by the etalon to align a target etalon output peak with a target wavelength of an output wavelength grid. The method includes modifying a bias current and a modulation current of a gain section of the tunable laser to achieve a defined output modulation amplitude and a defined extinction ratio.

A system includes N master oscillators to generate N master oscillator driving signals. The system includes N splitters to split each of the N master oscillator signals into M coherent signals with M being a positive integer greater than one. A modulator and fiber amplifier stage adjusts the relative phases of the M coherent signals and generates M×N amplified signals. The M×N amplified signals are aggregated into M clusters of N fibers. The system includes M spectral beam combination (SBC) modules to combine each of the M clusters. Each SBC module combines the M×N amplified signals at N wavelengths and generates M tiled output beams. Each SBC module employs a single dimensional (1D) fiber optic array to transmit one cluster of N amplified signals from the M signal clusters and generates one tiled output beam of the M tiled output beams.

A tunable laser has a first mirror, a second mirror, a gain medium, and a directional coupler. The first mirror and the second mirror form an optical resonator. The gain medium and the directional coupler are, at least partially, in an optical path of the optical resonator. The first mirror and the second mirror comprise binary super gratings. Both the first mirror and the second mirror have high reflectivity. The directional coupler provides an output coupler for the tunable laser.

Aspects of the present disclosure are directed to methods and apparatuses for generating laser light. As may be implemented in accordance with one or more embodiments, laser light is generated at a laser light source and is modulated in response to a frequency modulation signal, to generate a plurality of different wavelengths of laser light. The frequency modulation signal is generated, for each particular one of the wavelengths of laser light, at a respective seeding frequency corresponding to the particular one of the wavelengths in which the seeding frequency is different for each of the different wavelengths. Such an approach may, for example, involve generating the frequency modulation signal with a frequency generator circuit and using the frequency modulation signal to control an electro-optical modulator for modulating the wavelength of the laser light.

An optical device including an acousto-optic modulator (AOM), a laser, an upstream optical fibre extending between the laser and the AOM, a downstream optical fibre located downstream of the AOM and a reflector connected to the fibre downstream of the AOM. The optical device including the upstream fibre is a polarisation-maintaining optical fibre, and/or the downstream fibre is arranged so that a transit time of the optical beam through said downstream fibre from the AOM to the reflecting means is nonzero and shorter than or equal to half an open duration of the AOM, and/or the AOM includes a crystal in which the entrance/exit faces are planar and are at a nonzero angle to each other, and/or at least one of the two entrance/exit faces is at a nonzero angle to a direction of propagation of the acoustic wave in the crystal.

A wavelength tunable laser device includes a gain element positioned in an optical cavity that provides optical gain to an optical signal. A frequency shifter that generates a frequency shift as a function of time is positioned in the optical cavity. The optical cavity is configured so that a magnitude of the frequency shift as a function of time generated by the frequency shifter is substantially equal to a frequency separation of a cavity mode of the cavity such that an output of the cavity generates laser light having a wavelength that tunes as a function of time.

The invention relates to dispersion adjustment units for electromagnetic radiation having a spectral width, e.g., for laser pulses. The dispersion adjustment unit includes at least one dispersive element for producing angular dispersion in an angular dispersion region limited by two interaction regions of the electromagnetic radiation with the at least one dispersive element. In the angular dispersion region, individual spectral components of the electromagnetic radiation are associated with optical paths extending at an angle to one another. Furthermore, the dispersion adjustment unit includes an optical unit that is arranged in the angular dispersion region and includes an optical element that transmits the electromagnetic radiation. The optical element effects an incidence-angle-dependent parallel offset of the individual spectral components of the electromagnetic radiation with respect to the propagation of the individual spectral components before and after the optical unit.

An optical amplifier of the present disclosure includes an optical resonator that includes an amplification fiber capable of amplifying signal light having one or more propagation modes and resonates at least one propagation mode of the signal light amplified by the amplification fiber; an excitation light source that outputs excitation light for exciting the amplification fiber; and a multiplexer that multiplexes the signal light and the excitation light, in which the optical resonator includes a gain clamp setting unit which sets gain clamp for at least one propagation mode out of a plurality of propagation modes resonating in the optical resonator.

A device comprises three elements. The first element, comprising an optical gain structure and a laser cavity mirror structure, couples light to the second element, comprising a phase tuner. The second element couples phase tuned light to the third element. The third element, comprising an optical resonator with first and second coupler/splitter structures, provides a primary optical output from the second coupler/splitter structure. Light coupled into the optical resonator through the first coupler/splitter structure and then coupled out of the optical resonator though the first coupler/splitter structure is injected back into the optical gain structure through the second element. Light coupled out of the optical resonator through the second coupler/splitter structure is provided as the primary optical output. Characteristic of the coupler/splitter structures and the optical resonator are selected such that the light injected back into the optical gain structure reduces linewidth, and noise in primary optical output is suppressed.