Disclosed is a system for generating a spatially localized, high-intensity laser beam, including: a laser source designed to generate a burst of N laser pulses with a duration of less than or equal to one picosecond, the N laser pulses having a first repetition frequency greater than or equal to 0.5 gigahertz; a resonant optical cavity designed to receive and store the burst of N laser pulses, the resonant optical cavity being designed to focus the burst of N laser pulses in an interaction region of the resonant optical cavity; and a servo control system designed to control the first repetition frequency relative to the roundtrip distance in the resonant optical cavity, such that the N pulses of the burst are superimposed temporally and spatially by constructive interferences in the interaction region so as to form one giant ultra-short and high-energy pulse.

The present invention discloses a high-peak-power single-frequency narrow-linewidth nanosecond fiber laser based on a triangular pulse, wherein the laser includes: pulsed laser generated by the laser seed injecting into a first power pre-amplifier through a first isolator, and then injecting into a second pre-amplifier and then injecting into a power amplifier; wherein triangle-shaped pulsed laser with fast rising edge is obtained by using electro-optic and acousto-optic modulator to modulate continuous wave single-frequency laser or a single-frequency semiconductor laser directly modulated by radio frequency signal; single-frequency triangle-shaped pulsed laser is employed as the laser source according to the characteristics of narrow intrinsic linewidth and suppression of linewidth broadening caused by SPM, and the power of pulsed laser is amplified through the MOPA system.

Provided are an optical equalizer, a method, and a program which are configured to be capable of flattening a tilt characteristic of a wavelength division multiplexed optical signal with a simple configuration. The optical equalizer includes a detection unit configured to detect a tilt characteristic on the basis of intensities of at least two optical signals among a plurality of optical signals multiplexed into a wavelength division multiplexed optical signal, an optical attenuation unit configured to attenuate an intensity of the wavelength division multiplexed optical signal by an optical attenuation amount, and an optical amplification unit configured to amplify the attenuated wavelength division multiplexed optical signal on the basis of a gain characteristic associated with an intensity of the attenuated wavelength division multiplexed optical signal. In the optical equalizer, the optical attenuation amount is controlled based on the tilt characteristic and the gain characteristic.

Apparatus and methods for mitigating transverse mode instabilities (TMI) in high power fiber amplifiers that does not depend on active feedback loops. The apparatus and method involve the modulation of the amplitude and/or phase of selected spatial mode components of an input signal beam to increase the TMI threshold of the amplifier. Once the desired modal adjustments are made, the beam is input to a mode multiplexer whereupon an optimized output beam can be input to the active fiber of the amplifier system. By increasing the TMI threshold of the amplifier, the amplifier can be operated at higher power before TMI sets in. A control stage of the fiber amplifier system includes (a) a (seed) beam splitting section; (b) an amplitude and phase control component; and (c) a mode multiplexer that maps multiple individual signal beams to different fiber modes.

An optical amplification device includes: a laser medium that amplifies input light to generate output light; an excitation light source that supplies excitation light used for amplifying the input light, to the laser medium; a resonator that includes a pair of first optical elements and disposed to optically face each other with the laser medium interposed between the first optical elements and that resonates generated light generated in the laser medium through the supply of the excitation light; and an optical switch disposed on an optical path of the resonator between the pair of first optical elements.

A WDM seed beam source for a fiber laser amplifier system that includes a number of master oscillators that generate seed beams at different wavelengths and a spectral multiplexer that multiplexes all of the seed beams onto a single fiber. An EOM modulates the combined seed beams on the single fiber and a spectral demultiplexer then separates the modulated seed beams into their constituent wavelengths on separate fibers before the seed beams are amplified and spectrally combined. The fiber laser amplifier system includes a separate fiber amplifier that amplifies the separated seed beams, an emitter array that directs the amplified beams into free space, beam collimating optics that focuses the uncombined beams, and an SBC grating responsive to the collimated uncombined beams that spatially combines the collimated uncombined beams.

A tunable or swept laser architecture that is appropriate for swept source optical coherence tomography and other applications including spectroscopy employing a cat's-eye configuration with a preferably transmissive tilt tuned interference thin film filter.

An apparatus (such as a laser-based system) and method for providing optical pulses in a broad range of pulse widths and pulse energies uses a pulse slicer which is configured to slice a predefined portion having a desired pulse width of each of the one or more output optical pulses from a laser oscillator, in which timings of a rising edge and a falling edge of each sliced optical pulse relative to a time instance of a maximum of the corresponding each of the one or more output optical pulses from the laser oscillator, are chosen at least to maximize amplification efficiency of the optical amplifier, which may be located after the pulse slicer, and to provide the one or more amplified output optical pulses each having the desired pulse energy and pulse width.

In coherent beam combining, the beams can be phase-modulated with a pseudo-random bit sequence (PRBS) to prevent stimulated Brillouin scattering (SBS) downstream. To coherently combine the phase-modulated beams, however, the PRBS waveforms should be true-time-delayed to within a small fraction of the bit duration. Traditionally, this true time delay is achieved by cutting optical fibers to length or with optical trombones. But trimming fibers is hard to do precisely, and optical trombones have large insertion loss. In addition, the path length mismatch varies as the fibers heat up and/or vibrate. Here, the beams are generated from a kilohertz linewidth seed split among N>1 (e.g., N=100) arms. Each arm is phase-modulated with a separate copy of the unique PRBS pattern. The relative phase of the PRBS patterns is stabilized by phase-locking the master oscillators used to read out the PRBS patterns. The PRBS patterns can be phase shifted with respect to one another to compensate for physical path length mismatches of the optical fibers. Scanning the relative phase of the PRBS pattern used to modulate different arms yields a cross-correlation peak in combined power when the phases are matched at the combination plane.

A compact diode laser achieves high-power, short duration output pulses by separating the lasing action from the pulse-generating mechanism. A diode seed source is configured for gain-switching via a variable RF source. A time lens element includes an intensity modulation device, a phase modulation device, and a pulse compressor. The intensity modulation device carves shorter pulses from the long gain-switched seed pulses, the phase modulation device adds chirp, and the pulse compressor compensates for the chirp while producing high-power short-duration output pulses.