The systems and methods described herein relate to solid-state light sources capable of generating radiation beams for, but not limited to, the treatment of surfaces, bulk materials, films, and coatings. The solid-state ultraviolet source optically combines the light output of at least two and preferably as many four independently controllable discrete solid-state light emitters to produce a light beam that has a controllable multi-wavelength spectrum over a wide range of wavelengths (i.e. deep UV to near-IR). Specific features of this light source permit changes in the spectral, spatial and temporal distribution of light for use in curing, surface modification and other applications.