The invention features an apparatus and an associated method for illuminating a target area. The apparatus includes reflectors defining a first optical cavity. The first optical cavity defines a first set of longitudinal modes. The apparatus includes a first gain medium defining a first gain band. The first gain medium is configured to cause a plurality of the longitudinal modes of the first set to oscillate over an oscillation band within the first gain band when the first gain medium is pumped at an operative level. The apparatus includes a first optical waveguide positioned within the first optical cavity. The first optical waveguide has a length selected to cause a temporal coherence length of light emitted from the first optical cavity to be shorter than a scattering distance associated with the target area.