It is necessary to reduce the power consumption of a plurality of optical amplifiers when there is a difference in the required pumping power between the plurality of optical amplifiers; therefore, an optical amplifying apparatus according to an exemplary aspect of the invention includes a plurality of optical amplifying means for amplifying a plurality of optical signals, each of the plurality of optical amplifying means including a gain medium; a plurality of laser light generating means for generating a plurality of laser beams; at least one optical coupling means for coupling the plurality of laser beams variably in accordance with a coupling factor and outputting a plurality of excitation light beams, each of the plurality of excitation light beams exciting the gain medium; and controlling means for controlling the coupling factor and an output power of each of the plurality of laser light generating means.

A system for pumping laser sustained plasma is disclosed. The system includes a plurality of pump modules configured to generate respective pulses of pump illumination for the laser sustained plasma, wherein at least one pump module is configured to generate a train of pump pulses that is interlaced in time with another train of pump pulses generated by at least one other pump module of the plurality of pump modules. The system further includes a plurality of non-collinear illumination paths configured to direct the respective pulses of pump illumination from the plurality of pump modules into a collection volume of the laser sustained plasma.

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.

An optical system, apparatus, or method can comprise or implement a seed module to generate and output electromagnetic radiation at a predetermined amplitude and at a predetermined wavelength. The seed module can include at least one non-hollow core optical fiber and at least one hollow core optical fiber. One at least one non-hollow core optical fiber can be optically coupled to one at least one hollow core optical fiber. The non-hollow core optical fiber and the hollow core optical fiber may receive and pass electromagnetic radiation emitted from a laser diode or amplifier.

A beam shaper array assembly including a beam source that provides a plurality of beams having a low fill factor profile. The assembly also includes an input beam shaper array having cells positioned adjacent to each other, where each cell includes an input beam shaper that receives one of the plurality beams and is shaped to cause the beam to expand as it propagates away from the input array to be converted from the low fill factor profile to a high fill factor profile. The assembly further includes an output beam shaper array having cells positioned adjacent to each other, where each cell includes an output beam shaper that receives one of the converted beams and is shaped to cause the beam to stop expanding so that the output array provides a plurality of adjacent beams with minimal overlap and a minimal gap between the beams.

An amplified spontaneous emission (ASE) light source and a method for using the ASE light source are provided. The ASE light source may include a seed stage light source for providing a light beam to be amplified. The apparatus may include a tunable element coupled to the seed stage light source configured for filtering a portion of the light beam from the seed stage light source. The apparatus may include a loopback circuit coupled to the tunable element, the loopback circuit comprising a booster stage element for amplifying light from the tunable element.

A high-power laser beam with an arbitrary intensity profile is produced. Such beam has a variety of uses including for laser materials processing such as powder bed fusion additive manufacturing. Several challenges in additive manufacturing are mitigated with the present non-uniform intensity laser profiles. Nonuniform shapes include a set of intensity pixels in a line that could print a wide stripe area instead of just a single line. One example uses the multimode interference pattern from the output of a ribbon fiber which is imaged onto a work piece. The interference pattern is controlled to allow turning on or off of pixels along a line which can be used to shape the beam and form the additively manufactured part.

An optical amplifier includes a light source that generates excitation light in a wavelength band for Raman-amplifying signal light, an input unit that inputs the signal light and the excitation light to an optical fiber, and a processor connected to the light source. The processor executes a process including: acquiring a gain reduction amount of Raman amplification according to power of the signal light input to the optical fiber; determining a target gain based on the gain reduction amount acquired; judging whether a Raman gain corresponding to power of spontaneous emission light generated when the signal light is Raman-amplified in the optical fiber achieves the target gain determined; and setting power of the excitation light according to a judging result at the judging.

Provided is a method for monitoring a pump laser of at least one optical amplifier in an optical transmission link in operation. The optical output power of the pump laser to be monitored depends on an injection current. The pump laser to be monitored is operated at an operating point defined by a given value of the injection current and a corresponding value of the optical output power. The method includes the steps of shifting the operating point of the pump laser to be monitored to at least one shifted operating point. The shifting is effected in such a way that the gain of the respective optical amplifier essentially reaches its steady state, determining information on the at least one shifted operating point, and using the information on the operating point and the at least one shifted operating point to determine information on the stage of aging of the pump laser to be monitored.

A pumping light source outputs pumping lights. A pumping light source outputs a pumping light. Optical multiplexers couple the pumping lights to a plurality of cores. The optical multiplexer couples the pumping light to the clad. A pumping light source drive unit drives a pumping light source. A pumping light source drive unit drives a pumping light source. A monitoring unit outputs a monitoring signal indicating a monitoring result of the number of wavelengths used in each of optical signals amplified by the plurality of the cores. The control unit controls the power of the pumping lights based on the monitoring signal. The control unit controls the power of each of the pumping lights in accordance with the number of wavelengths used in each of the optical signals and controls the power of the pumping light so that signal qualities of the optical signals fall within a prescribed range.