An excitation light source apparatus capable of assuring an excellent optical transmission characteristic even at occurrence of a gain tilt is provided. The excitation light source apparatus comprises an excitation light outputting means, a control signal detection means, a control signal detection means, an excitation light control means, and a multiplexing means. The excitation light outputting means outputs excitation light for Raman amplification. The control signal detection means detects a control signal of the excitation light outputting means from beams of WDM signal light transmitted through optical fibers in an upstream direction and a downstream direction. The excitation light control means controls the excitation light outputting means, based on the control signal. The multiplexing means multiplexes the excitation light and each of the beams of the WDM signal light, and outputs the respective multiplexed beams of light to the optical fiber.

A high-voltage pulse generation device configured to apply a pulsed high voltage to the space between a pair of discharge electrodes disposed in a laser chamber of a gas laser apparatus includes n transformer cores that form a transformer, where n is a natural number greater than or equal to two, n primary electric circuits of the transformer, the n primary electric circuits each having a first terminal connected to a reference potential and a second terminal connected to a charger, the n primary electric circuits each including one or more primary coils, one or more diodes connected in parallel to the one or more primary coils, and one or more pulse generators connected in parallel to the one or more primary coils, and a secondary electric circuit of the transformer, the secondary electric circuit including a secondary coil and connected to the pair of discharge electrodes.

A high voltage pulse generation device includes n transformer cores configuring a transformer, n being a natural number of 2 or more, each of the n transformer cores being configured to form a magnetic circuit along a first plane and to have a width in a first direction parallel to the first plane larger than a width in a second direction parallel to the first plane and perpendicular to the first direction; n primary electric circuits of the transformer connected in parallel to each other, each of the n primary electric circuits including at least one primary coil, and m pulse generation units connected in parallel to the at least one primary coil, m being a natural number equal to or more than 2; and a secondary electric circuit of the transformer including a secondary coil and connected to a pair of discharge electrodes.

The present invention is to provide a backscattered light amplification device, an optical pulse test apparatus, a backscattered light amplification method, and an optical pulse test method for amplifying a desired propagation mode of Rayleigh backscattered light with a desired gain by stimulated Raman scattering in a fiber under test having the plurality of propagation modes. The backscattered light amplification device according to the present invention is configured to control individually power, incident timing, and pulse width of a pump pulse for each propagation mode when the pump pulse is incident in a plurality of propagation modes after the probe pulse is input to the fiber under test in any propagation mode.

A compact diode laser achieves high-power, short duration output pulses by separating the lasing action from the pulse-generating mechanism. A diode seed source is configured for gain-switching via a variable RF source. A time lens element includes an intensity modulation device, a phase modulation device, and a pulse compressor. The intensity modulation device carves shorter pulses from the long gain-switched seed pulses, the phase modulation device adds chirp, and the pulse compressor compensates for the chirp while producing high-power short-duration output pulses.

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.

Disclosed are a method, device and system for dynamically controlling a gain of a Raman optical fiber amplifier. The method comprises: determining whether a target gain falls within a gain mask range; if the target gain falls within the gain mask range, directly locking a gain to the target gain; and if the target gain falls outside the gain mask range, locking the gain to a corresponding maximum gain in the gain mask range, and gradually increasing the locked gain according to a preset first step length until the target gain is reached or until at least one pump laser reaches a maximum output power. The invention enables an optical fiber amplifier to respond quickly to a change in an input optical signal, ensures gain stability, and ensures that no power overshoot or undershoot occurs in the non-switched optical channels in an optical path. Moreover, the invention minimizes an amount of time required to complete switching between gains.

An electrodeless laser-driven light source includes a laser source that generates CW sustaining light. A pump laser generates pump light. A Q-switched laser crystal is positioned to receive the pump light and generates pulsed laser light in response to the generated pump light that propagates to a breakdown region in a gas filled bulb comprising an ionizing gas. A detector detects plasma light generated by a CW plasma located at least partly in a CW plasma region in the gas filled bulb comprising the ionizing gas and generates a detection signal. A controller generates control signals that control the pump light to the Q-switched laser crystal so as to extinguish the pulsed laser light within a time delay after the detection signal exceeds a threshold level.

A control system includes a field-programmable gate array (FPGA), a digital-to-analog conversion (DAC) circuit, an external TEC driver, and a pump chip. The field-programmable gate array (FPGA) includes a pump driver and a thermoelectric-cooler (TEC) controller. The digital-to-analog conversion (DAC) circuit is coupled to the FPGA. The external TEC driver is external to the FPGA and coupled to the FPGA. The pump chip includes a pump and a TEC and is coupled to the DAC circuit and the external TEC driver.

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.