Article for detecting power drift in the putout of a diode array source

A method and article for monitoring and controlling power drift in the output of a diode array is described. The diode array is used, for example, as a light pump for a fiber laser. In one embodiment, an improved fiber laser includes the light pump, which launches light into a laser cavity. The fiber laser further includes a sampler operable to receive at least a portion of the light before it is launched into the laser cavity. The sampled portion represents a known fraction of the total light signal generated by the light pump. In some embodiments, the sampled light is directed, via the sampler, to a photodetector. The photodetector converts the sampled light into a first electrical signal and delivers it to a processor. The processor is operable to compare the electrical signal with a set-point signal representative of a desired power output of the sampled portion of the launched light. To the extent that a differential exists between the set point signal and the first electrical signal, the desired optical power is not being launched into the lasing cavity. If such a differential exists, the processor generates and sends a control signal to a controllable current source. The control signal is operable to increase or decrease the current delivered from the controllable current source to the light pump to correct power drifts in light pump output.