An optical amplifier uses, in a gain medium, a multicore optical fiber having a plurality of cores, and comprises: an input-light power monitor that monitors the optical power of input light to the plurality of cores of the multicore optical fiber; an output-light power monitor that monitors the optical power of medium-passed output light from the plurality of cores that has passed through the multicore optical fiber; a crosstalk monitor that monitors the amount of inter-core crosstalk among the plurality of cores; and a controller that controls the pump-light power of pump light superimposed on the input light to the plurality of cores on the basis of the monitored optical power of input light, the monitored optical power of output light, and the monitored amount of inter-core crosstalk.

A laser device includes: a light source including laser diodes; a processor that holds: a maximum current value of a driving current applied to the laser diodes, and a maximum power value of a power of light emitted from the light source; and a memory, coupled to the processor, that stores a relationship between a magnitude of the driving current, a magnitude of the power of the light, and a degree of deterioration of the light source. The processor further refers to the memory and estimates the degree of deterioration from the maximum current value and the maximum power value.

A laser irradiating device preferably includes: a reflector having a receiving space formed therein; a flash lamp inserted and mounted in the reflector to generate light; a laser rod for resonating light incident from the flash lamp to emit a laser; a capacitor for storing, for a predetermined time interval, voltage to be supplied to the flash lamp; a digital variable resistor unit for outputting different voltages according to configured resistance values; a voltage increasing unit for increasing voltage input from the digital variable resistor unit and supplying the increased voltage to the capacitor; a control unit which stores resistance values corresponding to laser irradiating levels and configures a resistance value corresponding to the configured laser irradiating level; and a trigger circuit unit turned on according to a control of the user to supply a charge voltage of the capacitor to the flash lamp.

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.

Disclosed are an online program update method and device for an optical amplifier. The method comprises: when a program update instruction is sent, a Microcontroller Unit MCU receiving update programs of MCU and a programmable logic device FPGA, storing them in a program memory device, and sending an update instruction to FPGA; FPGA terminating operations of a digital-to-analog converter DAC according to the instruction and a current state remaining unchanged; MCU loading new codes of MCU and FPGA while DAC remains in state of halting refreshing; and after MCU and FPGA run the new codes, reading previously stored data, and starting switching from a previous operation state to enter normal operation state. On basis of conventional optical amplifier control, the invention combines characteristics of MCU and FPGA, and ensures uninterrupted service of optical amplifiers, achieving smooth transition of service, thereby improving stability and reliability of whole optical communications systems.

The present invention provides an optical amplifier and a control method therefor, with which it is possible to stably control an optical amplifier that uses a multicore optical fiber. The optical amplifier uses, in a gain medium, a multicore optical fiber having a plurality of cores, and comprises: an input-light power monitor that monitors the optical power of input light to the plurality of cores of the multicore optical fiber; an output-light power monitor that monitors the optical power of medium-passed output light from the plurality of cores that has passed through the multicore optical fiber; a crosstalk monitor that monitors the amount of inter-core crosstalk among the plurality of cores; and a controller that controls the pump-light power of pump light superimposed on the input light to the plurality of cores on the basis of the monitored optical power of input light, the monitored optical power of output light, and the monitored amount of inter-core crosstalk.

To limit the number of excitation laser diodes (LDs) in an optical amplification device provided with a redundant excitation LD configuration, the optical amplification device is provided with: an excitation unit which outputs a plurality of excitation lights generated by a plurality of excitation light sources; a first distributing unit of which inputs are connected to the plurality of excitation light sources and which branches input lights and then outputs branched lights as a plurality of first distributed lights; a plurality of second distributing units of which inputs are connected to the first distributing unit and which combines and branches input lights and then outputs branched lights as a plurality of second distributed lights; and a plurality of gain mediums which are respectively excited by the plurality of second distributed lights.

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.

At least one beam of pump pulses is combined in a nonlinear process with a plurality of monochromatic beams, each containing signal pulses of a unique wavelength. This produces an ensemble of beams of pulses having wavelengths of medium length. Then, all of the pulses in all of the beams in the ensemble are subject to second harmonic generation, optical parametric amplification, sum-frequency generation, or combinations to reduce the wavelengths of those pulses to ultraviolet wavelengths, thereby creating driver pulses. Driver beams made up of those reduced-wavelength driver pulses can then be focused upon a fuel pellet.

A burst logging system logs and transmits to a local or remote computing system event data related to errors in and or potential failures of laser system components. The system further provides for capturing data at different rates from different sensors, synchronization of data capture associated with system events and the possibility for aggregation of data from multiple systems, which can in turn be leveraged to predict and or remediate future system events.