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.

A pulsed current source comprises a power source, a discharge capacitor, and an inductive element. The discharge capacitor is selectively coupled to either of the power source or the inductive element. When coupled to the power source, the discharge capacitor is charged. The inductive element can be connected to a load. The load can have a current-dependent impedance. When the discharge capacitor is coupled to the inductive element, the discharge capacitor discharges through the inductive element and the load. The discharge capacitor and the inductive element are configured so that the current through the load exhibits a substantially linear rise in a linear operational region. The inductive element is configured to saturate during discharge of the capacitor through the load, so that the saturation of the inductive element causes the current through the load to continue to rise in a substantially linear fashion.

A pulsed current source comprises a power source, a discharge capacitor, and an inductive element. The discharge capacitor is selectively coupled to either of the power source or the inductive element. When coupled to the power source, the discharge capacitor is charged. The inductive element can be connected to a load. The load can have a current-dependent impedance. When the discharge capacitor is coupled to the inductive element, the discharge capacitor discharges through the inductive element and the load. The discharge capacitor and the inductive element are configured so that the current through the load exhibits a substantially linear rise in a linear operational region. The inductive element is configured to saturate during discharge of the capacitor through the load, so that the saturation of the inductive element causes the current through the load to continue to rise in a substantially linear fashion.

A laser system may include a laser resonator configured to emit an input laser beam having an elliptical cross-sectional shape. The laser system also may include first reflective device configured to reflect the input laser beam to produce a first reflected laser beam. The first reflective device may include a spherical surface for reflecting the input laser beam. The laser system also may include a second reflective device configured to reflect the first reflected laser beam to produce a second reflected laser beam. The laser system also may include a coupling device configured to focus the second reflected laser beam to produce an output laser beam. The coupling device may include a spherical surface for receiving the second reflected laser beam. The laser system also may include an optic fiber configured to transmit the output laser beam for emission of the output laser beam onto a target area.

A laser system may include a laser resonator configured to emit an input laser beam having an elliptical cross-sectional shape. The laser system also may include first reflective device configured to reflect the input laser beam to produce a first reflected laser beam. The first reflective device may include a spherical surface for reflecting the input laser beam. The laser system also may include a second reflective device configured to reflect the first reflected laser beam to produce a second reflected laser beam. The laser system also may include a coupling device configured to focus the second reflected laser beam to produce an output laser beam. The coupling device may include a spherical surface for receiving the second reflected laser beam. The laser system also may include an optic fiber configured to transmit the output laser beam for emission of the output laser beam onto a target area.

Systems and methods for imaging in the short wave infrared (SWIR), photodetectors with low dark current and associated circuits for reducing dark currents and methods for generating image information based on data of a photodetector array. A SWIR imaging system may include a pulsed illumination source operative to emit radiation pulses in the SWIR band towards a target resulting in reflected radiation from the target; (b) an imaging receiver including a plurality of Ge PDs operative to detect the reflected SWIR radiation and a controller, operative to control activation of the receiver for an integration time during which the accumulated dark current noise does not exceed the time independent readout noise.

A laser system includes a first laser cavity to output a laser light along a first path, a first mirror to receive the laser light from the first laser cavity, and redirect the laser light along a second path that is different than the first path, a second mirror to receive the laser light from the first mirror, and redirect the laser light along a third path that is different than the first path and the second path, a beam splitter located at a first position on the third path, a beam combiner located at a second position on the third path; and a coupling lens assembly, the coupling lens assembly including a lens located at a third position on the third path, wherein the coupling lens assembly moves the lens in x-, y-, and x-directions.

A MOPA laser system that includes a seed laser configured to output pulsed laser light, an amplifier configured to receive and amplify the pulsed laser light emitted by the seed laser; and a pump laser configured to deliver a pump laser beam to both the seed laser and the amplifier and a variable attenuator configured to eliminate missing Q-switched pulses.

A laser energy meter circuit, method, and system for measuring excitation and ionization of a reactant. The laser energy meter circuit includes a pyroelectric detector head configured to receive laser pulses and output current signals; an amplifier having a first amplifier input and an amplifier output configured to generate amplified voltage signals; a sample-and-hold circuit; a trigger circuit connected to a second sample-and-hold input, wherein the trigger circuit is configured to receive a TTL signal and generate a delayed output pulse, Q.sub.1 and a trigger signal, Q.sub.2; a sample-and-hold circuit output configured to output the maximum pulse voltage when the trigger signal is received at the second sample-and-hold input; a switched capacitor bank connected to the sample-and-hold circuit output; and a peak detector circuit configured to measure a magnitude of the maximum pulse voltage and generate an averaged DC maximum pulse voltage signal.

A laser energy meter circuit, method, and system for measuring excitation and ionization of a reactant. The laser energy meter circuit includes a pyroelectric detector head configured to receive laser pulses and output current signals; an amplifier having a first amplifier input and an amplifier output configured to generate amplified voltage signals; a sample-and-hold circuit; a trigger circuit connected to a second sample-and-hold input, wherein the trigger circuit is configured to receive a TTL signal and generate a delayed output pulse, Q.sub.1 and a trigger signal, Q.sub.2; a sample-and-hold circuit output configured to output the maximum pulse voltage when the trigger signal is received at the second sample-and-hold input; a switched capacitor bank connected to the sample-and-hold circuit output; and a peak detector circuit configured to measure a magnitude of the maximum pulse voltage and generate an averaged DC maximum pulse voltage signal.