Systems and methods for stabilizing mid-infrared light generated by difference frequency mixing may include a mode locked Er fiber laser that generates pulses, which are split into a pump arm and a wavelength shifting, signal arm. Pump arm pulses are amplified in Er doped fiber. Shifting arm pulses are amplified in Er doped fiber and shifted to longer wavelengths in Raman-shifting fiber or highly nonlinear fiber, where they may be further amplified by Tm doped fiber, and then optionally further wavelength shifted. Pulses from the two arms can be combined in a nonlinear crystal such as orientation-patterned gallium phosphide, producing a mid-infrared difference frequency, as well as nonlinear combinations (e.g., sum frequency) having near infrared and visible wavelengths. Optical power stabilization can be achieved using two wavelength ranges with spectral filtering and multiple detectors acquiring information for feedback control. Controlled fiber bending can be used to stabilize optical power.

A method for generating pulsed laser radiation in the spectral range from 860 nm to 1000 nm is disclosed, including the steps of generating pulsed laser radiation in the spectral range from 1500 nm to 1600 nm, preferably at a wavelength of 1560 nm; shifting the wavelength of the pulsed laser radiation to a longer wavelength of at least 1720 nm, and preferably to 1840 nm; amplifying the wavelength-shifted pulsed laser radiation in a Thulium-doped gain medium so that the Thulium-doped gain medium is pumped in an in-band pumping scheme; and frequency-doubling the amplified wavelength-shifted pulsed laser radiation. A laser system suitable for practicing the method is also disclosed.

Apparatuses and methods are disclosed for applying laser energy having desired pulse Characteristics, including a sufficiently short duration and/or a sufficiently high energy for the photomechanical treatment of skin pigmentations and pigmented lesions, both naturally-occurring (e.g., birthmarks), as well as artificial (e.g., tattoos). The laser energy may be generated with an apparatus having a resonator with the capability of switching between a modelocked pulse operating mode and an amplification operating mode. The operating modes are carried out through the application of a time-dependent bias voltage, having waveforms as described herein, to an electro-optical device positioned along the optical axis of the resonator.

A laser architecture for selectively producing short high-energy laser pulses having octave-spanning, continuous tunability. Two oppositely chirped pulses are used in combination with a pair of tunable pulse stretcher/compressors to produce a short, high-energy, tunable, broadband pulse.

Chirped pulse amplification (CPA) systems configured to generate and amplify multi-pulses are described. The nonlinear interaction of pulses can generate a multiple pulse pack with a dense time separation between pulses. Reducing or eliminating the nonlinear interaction can be provided by spectrally and/or temporally splitting pulses in the chirped amplification system.

A high-power mode-locked laser system is disclosed herein which includes at least one pump source, at least one laser cavity formed by at least one high reflector and at least one output coupler, and at least one ytterbium-doped optical crystal positioned within the laser cavity in communication with the pump source, the ytterbium-doped optical crystal configured to output at least one output signal of at least 20 W, having a pulse width of 200 fs or less, and a repetition rate of at least 40 MHz.

A pulse laser apparatus (100) for creating laser pulses (1), in particular soliton laser pulses (1), based on Kerr lens mode locking of a circulating light field in an oscillator cavity (10), comprises at least two resonator mirrors (11, 12, . . . ) spanning a resonator beam path (2) of the oscillator cavity (10), at least one Kerr-medium (21, 22, 23) for introducing self-phase modulation and self-focusing to the circulating light field in the oscillator cavity (10), at least one gain-medium (31) for amplifying the circulating light field in the oscillator cavity (10), and a tuning device (40) for setting a first mode-locking condition and a second mode-locking condition of the oscillator cavity (10) such that an intra-cavity threshold-power for mode-locking at the first mode-locking condition is lower than that at the second mode-locking condition, wherein the first mode-locking condition is adapted for starting or shutting-down of the Kerr lens mode locking and the second mode-locking condition is adapted for continuous Kerr lens mode locking and a resonator-internal peak-power of the circulating light field is higher at the second mode-locking condition than at the first mode-locking condition. Furthermore, a method of operating a pulse laser apparatus is described.

Wavelength-tunable source of pulsed laser radiation for VIS-NIR spectroscopy which consists of a pump source (1) forming bursts of picosecond pulses of high pulse repetition rate, and a synchronously pumped optical parametric oscillator (2). The pump source (1) comprises a solid-state regenerative amplifier (31) having one or two electro-optical switches (32,33) inside its resonator (44). The switches create partial transmission of the resonator for a time interval longer than a resonator roundtrip time, and eject a part of energy of a pulse circulating inside. Bursts of 5-10 ns duration are formed, which are filled with high peak power picosecond pulses. Pulse repetition rate of the order of GHz of pump pulses allows the construction of a compact optical parametric oscillator. The whole set of parameters ensures high energy efficiency, stability and an ability to provide output pulse bursts repeating at up to 10 kHz repetition rate.

Wavelength-tunable source of pulsed laser radiation for VIS-NIR spectroscopy which consists of a pump source (1) forming bursts of picosecond pulses of high pulse repetition rate, and a synchronously pumped optical parametric oscillator (2). The pump source (1) comprises a solid-state regenerative amplifier (31) having one or two electro-optical switches (32,33) inside its resonator (44). The switches create partial transmission of the resonator for a time interval longer than a resonator roundtrip time, and eject a part of energy of a pulse circulating inside. Bursts of 5-10 ns duration are formed, which are filled with high peak power picosecond pulses. Pulse repetition rate of the order of GHz of pump pulses allows the construction of a compact optical parametric oscillator. The whole set of parameters ensures high energy efficiency, stability and an ability to provide output pulse bursts repeating at up to 10 kHz repetition rate.

In one embodiment, a lidar system includes a light source configured to emit pulses of light. The lidar system also includes multiple optical links and multiple sensor heads. Each optical link couples the light source to a corresponding sensor head, and each optical link is configured to convey at least a portion of the emitted pulses of light from the light source to the corresponding sensor head. Each sensor head includes a scanner configured to scan pulses of light across a field of regard of the sensor head, where the scanned pulses of light include the portion of the emitted pulses of light conveyed from the light source to the sensor head by the corresponding optical link. Each sensor head also includes a receiver configured to detect at least a portion of the scanned pulses of light scattered or reflected by a target located downrange from the sensor head.