Abstract: Apparatus for providing optical radiation (15) comprising a pump source (19) and at least one first amplifying waveguide (1), characterised in that the first amplifying waveguide (1) emits optical radiation (15) in excess of 1400 nm when pumped by the pump source (19). In one embodiment, the pump source (19) comprises a plurality of laser diodes (3) and a plurality of second amplifying waveguides (2). The first amplifying waveguide (1) is pumped by the second amplifying waveguides (2). The second amplifying waveguides (2) are pumped by the laser diodes (3). The second amplifying waveguides (2) are configured to improve the beam quality of radiation emitted by the laser diodes (3). Advantageously, the apparatus can be configured such that the optical radiation (15) emitted by the first amplifying waveguide (1) has a higher brightness when the second amplifying waveguide (2) emits at a first wavelength.