Comparative analysis of the image quality at the output of a fiber bundle under active and passive conditions

The results are given of an experimental estimate of the quality of an image at the output of fiber laser amplifiers of transmission and reflection types. It is shown that the active regime of operation of a fiber bundle makes it possible to increase considerably the absolute value of the image contrast, compared with the passive regime. The resolution of a reflection-type fiber laser amplifier approaches the limit governed only by the diameters of the component fibers and is independent of the regularity of fiber packing in a bundle.