A laser that emits light at all available frequencies distributed throughout the spectral bandwidth or emission bandwidth of the laser in a single pulse or pulse train is disclosed. The laser is pumped or seeded with photons having frequencies distributed throughout the superunitary gain bandwidth of the gain medium. The source of photons is a frequency modulated photon source, and the frequency modulation is controlled to occur in one or more cycles timed to occur within a time scale for pulsing the laser.

The optical amplifier, which amplifies wavelength multiplexed signal light, comprises: a multi-core optical fiber which includes cladding and a first core and a second core disposed in the cladding, and which is doped with rare-earth ions; an excitation light source for supplying excitation light to the cladding of the multi-core optical fiber; and a wavelength demultiplexing means for separating the wavelength bands of the wavelength multiplexed signal light that has propagated through the first core. The signal light of a relatively long wavelength band among a plurality of wavelength bands separated by the wavelength demultiplexing means is caused to propagate through the second core, and is then multiplexed with the signal light of a relatively short wavelength band among the plurality of wavelength bands separated by the wavelength demultiplexing means, and the resultant multiplexed signal light is output.

The invention belongs to the field of lasers, more precisely to the field of constructional details of laser devices and laser devices for controlling intensity, frequency, length, polarization or direction of emitted rays. The present invention is an improved gain switched fiber laser, which enables changes of repetition frequency in a large range and which, at the same time, maintains a constant peak power and duration of generated laser pulses. The essence of the laser according to the invention is the pump system which is coupled to an oscillator and pumps the oscillator as well as the amplifier. The pump system comprises a primary and a secondary pump module, each at least with one pump laser diode, wherein the primary module generates short pump pulses and wherein the primary and secondary pump module operate at different peak powers. The power generated by the secondary module can be directly used to decrease the effect of active medium relaxation via spontaneous emission in-between laser pulses, which enables generation of short laser pulses on demand having constant parameters.

In one embodiment, a lidar system includes a light source configured to emit light at one or more wavelengths between 1200 nm and 1400 nm. The lidar system also includes a scanner configured to scan the emitted light across a field of regard of the lidar system and a receiver configured to detect a portion of the emitted light scattered by a target located a distance from the lidar system. The lidar system further includes a processor configured to determine the distance from the lidar system to the target based at least in part on a round-trip time for the portion of the emitted light to travel from the lidar system to the target and back to the lidar system.

An optical coupler includes N members. A Kth (K is an integer of 1 to N) member includes a MCF including P (P is an integer of N or greater) cores, and a marker disposed at a position closest to a first core, and at least one SCF. A core of the SCF of the Kth member is coupled to a coupled core other than the first core. Cores of the MCF of an Mth (M is an integer of 1 to N−1) member are connected to cores of the MCF of an (M+1)th member. A total number of SCF included in the N members is P. Each of P cores of the MCFs configured through the connection of the N members is connected to a core of one of the SCFs.

An optical coupler includes N members. A Kth (K is an integer of 1 to N) member includes a MCF including P (P is an integer of N or greater) cores, and a marker disposed at a position closest to a first core, and at least one SCF. A core of the SCF of the Kth member is coupled to a coupled core other than the first core. Cores of the MCF of an Mth (M is an integer of 1 to N−1) member are connected to cores of the MCF of an (M+1)th member. A total number of SCF included in the N members is P. Each of P cores of the MCFs configured through the connection of the N members is connected to a core of one of the SCFs.

Embodiments discussed herein refer to LiDAR systems and methods that enable substantially instantaneous power and frequency control over fiber lasers. The systems and methods can simultaneously control seed laser power and frequency and pump power and frequency to maintain relative constant ratios among each other to maintain a relatively constant excited state ion density of the fiber laser over time.

The system and method of using an ultra-short pulse mid and long wave infrared laser. The system is seeded with a 2 μm laser source having a pulse duration in the femtosecond range. The beam is stretched, to increase the pulse duration, and the beam is amplified, to increase an energy level of the laser beam. Both mid wave IR and long wave IR seed beams are first generated, and then amplified via one or more optical parametric chirped-pulse amplification stages. A compressor may be used to compress one or more of the output beams to achieve high peak power and controllable pulse duration in the output beams. The output beams may then be used to create atmospheric or material effects at km range.

The system and method of using an ultra-short pulse mid and long wave infrared laser. The system is seeded with a 2 μm laser source having a pulse duration in the femtosecond range. The beam is stretched, to increase the pulse duration, and the beam is amplified, to increase an energy level of the laser beam. Both mid wave IR and long wave IR seed beams are first generated, and then amplified via one or more optical parametric chirped-pulse amplification stages. A compressor may be used to compress one or more of the output beams to achieve high peak power and controllable pulse duration in the output beams. The output beams may then be used to create atmospheric or material effects at km range.

A device controller (16) for directing a drive current (12A) to a device (12) includes a current driven power source (40) that is electrically connected to the device (12); and a current adjuster (22) electrically connected to the power source (40) in parallel to the device (12). The current adjuster (22) selectively adjusts the drive current (12A) directed to the device (12). For a laser (12), the current adjuster (22) can adjust the drive current (12A) to modulate a center wavelength of an illumination beam (20) generated by the laser (12).