An optical pulse generation device includes an optical resonator of mode-locked type, a light source, and a waveform controller. The optical resonator includes an optical amplification medium and generates, amplifies, and outputs laser light. The light source is optically coupled to the optical resonator and supplies excitation light to the optical amplification medium. The waveform controller is arranged in the optical resonator, and controls a time waveform of the laser light within a predetermined period to convert the laser light into an optical pulse train including two or more optical pulses within a period of the optical resonator. The optical resonator amplifies the optical pulse train after the predetermined period and outputs the optical pulse train having amplified as the laser light.

A laser device comprises a first optical cavity comprising a first gain medium and a second optical cavity comprising a second gain medium. The first gain medium and the second gain medium generate light at respective different ranges of wavelengths. A synchronizer is optically coupled to both the first optical cavity and the second optical cavity and is configured to synchronize and mode-lock light from the first optical cavity and the second optical cavity. The laser device also includes a first optical filter and a second optical filter to filter the light from the first optical cavity and the second optical cavity respectively to output first filtered light pulses at a first predetermined range of wavelengths and second filtered light pulses at a second predetermined range of wavelengths.

A laser device comprises a first optical cavity comprising a first gain medium and a second optical cavity comprising a second gain medium. The first gain medium and the second gain medium generate light at respective different ranges of wavelengths. A synchronizer is optically coupled to both the first optical cavity and the second optical cavity and is configured to synchronize and mode-lock light from the first optical cavity and the second optical cavity. The laser device also includes a first optical filter and a second optical filter to filter the light from the first optical cavity and the second optical cavity respectively to output first filtered light pulses at a first predetermined range of wavelengths and second filtered light pulses at a second predetermined range of wavelengths.

A mode locking semiconductor disk laser (SDL) comprising a resonator terminated by first and second mirrors and folded by a third mirror is presented. The third mirror includes a semiconductor disk laser (SDL) suitable for generating a resonator field having a predetermined central wavelength .sub.0, while the second mirror includes an intensity saturable mirror suitable for mode locking the resonator field at the predetermined wavelength. The central wavelength of the reflectivity profile of the first and or second mirrors is shifted to a wavelength shorter than the central wavelength .sub.0 to suppress gain at wavelengths longer than the central wavelength .sub.0. By mismatching the reflectivity profile of the first and or second mirrors to that of the desired output wavelength provides a stable mode locked laser with significantly reduced noise.

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.

Embodiments herein describe a path length adjuster for, e.g., adjusting the length of an optical cavity of a laser. In one embodiment, the path length adjuster includes a circulator element for ensuring unidirectional lasing. The path length adjuster may also include one or more focusing elements such as a focusing lens and/or a collimator which directs received laser light at a mirror. The mirror is mounted on an actuator that moves the mirror in a direction parallel with the propagation of the laser light, thereby increasing or reducing the length of the ring cavity.

Disclosed is a system and a method for generating high-power laser pulses with very high repetition rate. The laser system includes an oscillator capable of generating a source laser beam including a series of sources pulses with femtosecond or picosecond duration at a first repetition frequency no lower than 800 megahertz and an optical amplifier system suitable for receiving and amplifying the series of source pulses at a second repetition frequency that is equal to or a multiple of the first repetition frequency, the multiple being a non-negative integer greater than or equal to two, so as to generate a series of laser pulses with very high repetition frequency.

Disclosed is a system and a method for generating high-power laser pulses with very high repetition rate. The laser system includes an oscillator capable of generating a source laser beam including a series of sources pulses with femtosecond or picosecond duration at a first repetition frequency no lower than 800 megahertz and an optical amplifier system suitable for receiving and amplifying the series of source pulses at a second repetition frequency that is equal to or a multiple of the first repetition frequency, the multiple being a non-negative integer greater than or equal to two, so as to generate a series of laser pulses with very high repetition frequency.

A method and apparatus for passively synchronising the repetition rate of two or more mode-locked lasers is described. The method and apparatus involve forming a first synchronising optical field (6) by separating a portion of an output field of a first mode-locked laser (2) and thereafter redirecting this synchronising optical field to form a driving signal for a second mode-locked laser (3). Employing these techniques results in systems with timing jitter of less than 1 fs. The method is independent of the wavelength and polarisation at which the mode-locked lasers operate and so is not limited to use with any particular type of mode-locked laser. Since the technique is passive it does not require the employment of electronics, variable time delay paths or additional non-linear optical crystals. Therefore, the method and apparatus are significantly less complex than those known in the art and are not power limited by additional non-linear optical processes. Part of the output (7) of the first mode-locked laser (2) is redirected via a beam splitter (9) and beam steering mirrors (11,12) and a half-wave plate (15) to a polariser (13) in the the beam line of the second mode-locked laser (3). The seeding and synchronising signal from the first mode-locked laser (2) may be perpendicularly polarized with respect to the polarization of the second mode-locked laser (3) and may have a different wavelength.

Low phase noise radio frequency (RF) sources generated by voltage controlled oscillators (VCOs) are described. Optical modulators driven by a VCO may be used to generate optical side-bands to cw lasers. The spectral extent of said side-bands can be increased via frequency broadening in highly nonlinear waveguides. Free running mode locked low phase noise comb oscillators can be used as reference oscillators to generate beat signals between those side-bands and individual comb modes at distal spectral regions, thereby creating an error signal used to reduce the phase noise of VCOs and the generation of low phase noise RF signals. VCO phase noise may be reduced by using free-running modelocked comb lasers phase locked to external frequency references, by omitting a reference comb and using a nonlinear interferometer for generating an error signal, or by locking a slave comb to the modulation frequency of an intra-cavity modulator driven by the VCO.