Orbital debt is removal (ODR) systems under the present approach may use a ground- or surface-based FEL and mirror system with sufficient power and both spatial and temporal resolution to both locate Category II OD (1 cm to 10 cm diameter) in low Earth orbit (LEO, 160 to 2000 km altitude) and remove these objects from orbit. Locating the Category II OD is performed by having, the light beam from an FEL and its beam director scan a volume of space of interest and then observing the light reflected from the OD. Removing the OD may include heating the OD to a sufficiently high temperature to evaporate the OD, changing the orbit of the OD such as to lower the perigee, or both. Megawatt-class MOPA FELs for, inter alia, removing OD, are described.

Apparatus for and methods of combining multiple, i.e., two or more laser beams to reduce even to the point of elimination a transverse gap between the two or more beams caused, for example, by a space between a coating on a surface of the mirror and the edge of the mirror, or by optic geometry, is avoided.

Apparatus for providing optical radiation (15), which apparatus comprises an optical input (13), a coupler (2), a first semiconductor amplifier (3), a controller (4), a preamplifier (61), a power amplifier (62) and an output fibre (5), wherein: the optical input (13) is for receiving input optical radiation (14); the optical input (13) is connected in series to the coupler (2), the first semiconductor amplifier (3), the preamplifier (61), the power amplifier (62), and the output fibre (5); the apparatus being characterized in that: the first semiconductor amplifier (3) comprises a waveguide (6) having a low reflecting facet (8); the first semiconductor amplifier (3) is in a double pass configuration such that the low reflecting facet (8) is connected to both the optical input (13) and the preamplifier (61) via the coupler (2); and the controller (4) is configured to cause the waveguide (6) of the first semiconductor amplifier (3) to operate in saturation thereby enabling the first semiconductor amplifier (3) to reduce non-linear effects in the preamplifier (61), the power amplifier (62), and the output fibre (5).

A supporting member supports a peeled end portion formed at an end portion in longitudinal direction representing first direction of an optical fiber, the optical fiber including: a core wire including a core and a cladding; and a jacket configured to enclose the core wire, the jacket being removed at the peeled end portion to expose the core wire. The supporting member includes: a first member; a second member fixed to the first member; a housing portion provided between the first member and the second member, the housing portion extending along the peeled end portion and being configured to house the peeled end portion; and a processed member housed in the housing portion and provided around the peeled end portion, the processed member being configured to cause transmission or scattering of light leaking from the peeled end portion.

A laser apparatus according to an aspect of the present disclosure includes a laser oscillator configured to emit a pulse laser beam, and a first optical pulse stretcher, a second optical pulse stretcher, and a third optical pulse stretcher that are disposed on an optical path of the pulse laser beam. When L1 represents an optical path length of a delay optical path of the first optical pulse stretcher, L2 represents an optical path length of a delay optical path of the second optical pulse stretcher, L3 represents an optical path length of a delay optical path of the third optical pulse stretcher, and n represents an integer equal to or larger than two, L2 is an integral multiple of L1 by an integer equal to or larger than two and L3 satisfies the following condition: (n−0.75)×L1≤L3≤(n−0.25)×L1.

A spectral feature selection apparatus includes a dispersive optical element arranged to interact with a pulsed light beam; three or more refractive optical elements arranged in a path of the pulsed light beam between the dispersive optical element and a pulsed optical source; and one or more actuation systems, each actuation system associated with a refractive optical element and configured to rotate the associated refractive optical element to thereby adjust a spectral feature of the pulsed light beam. At least one of the actuation systems is a rapid actuation system that includes a rapid actuator configured to rotate its associated refractive optical element about a rotation axis. The rapid actuator includes a rotary stepper motor having a rotation shaft that rotates about a shaft axis that is parallel with the rotation axis of the associated refractive optical element.

An all-fiber configuration system and method for generating temporally coherent supercontinuum pulsed emission are provided. The system includes a sequential structure of all-fiber sections including: a fiber laser seed source to produce a seed pulse with given optical properties; a stretching section including an optical fiber to temporally stretch the seed pulse; an amplification section including an active optical fiber, doped with a rare earth element, to amplify the stretched pulse by progressively stimulating radiation of active ions of the doped active optical fiber; a compressing section to temporally compress the amplified pulse; and a spectrum broadening section including an ANDi microstructured fiber that spectrally broadens the compressed pulse by a nonlinear effect of Self Phase Modulation (SPM) while maintaining the temporal coherence of the pulse.

An all-fiber laser oscillator comprises a laser cavity, an amplification fiber, a plurality of diode lasers, and at least one side-pump signal-and-pump combiner (combiner). The combiner comprises a double-clad fiber (DCF) and four or more multimode fibers (MMFs). DCF comprises a first taper portion, whereas each of MMFs comprises a second taper portion fused around DCF. MMFs are configured to carry a portion of combined optical energy (COE) and to couple to DCF. The first taper portion can partially compensate a beam divergence created by the second taper portion, thereby increasing a coupling efficiency of COE coupled from MMFs to DCF with improved thermal performance. In a coupling portion, a refractive index difference between MMFs and DCF is configured to form a backward coupling barrier to suppress an optical energy in DCF from coupling into MMFs, thereby protecting the plurality of diode lasers from damage.

A laser system having a multi-pass amplifier system which includes at least one seed source configured to output at least one seed signal having a seed signal wavelength, at least one pump source configured to output at least one pump signal, at least one multi-pass amplifier system in communication with the seed source and having at least one gain media, a first mirror, and at least a second mirror therein, the gain media device positioned between the first mirror and second mirror and configured to output at least one amplifier output signal having an output wavelength range, the first mirror and second mirror may be configured to reflect the amplifier output signal within the output wavelength range, and at least one optical system may be in communication with the amplifier system and configured to receive the amplifier output signal and output an output signal within the output wavelength range.

Systems, apparatuses, methods, and computer program products are provided for controlling a laser source that includes two laser discharge chambers. An example laser control system can include a first pulsed powertrain including a first independent circuit configured to generate a first resonant charging supply (RCS) output voltage. The first RCS output voltage can be configured to drive a first laser discharge chamber. The example laser control system can further include a second pulsed powertrain including a second independent circuit configured to generate a second RCS output voltage independent from the first RCS output voltage. The second RCS output voltage can be configured to drive a second laser discharge chamber independent from the first laser discharge chamber.