The invention relates to sources of optical radiation wherein polarized radiation from first and second rows of light emitters is first collimated and combined into two combined beam using first and second rows of collimating and beam re-directing elements, respectively, and then polarization multiplexed to form a polarization-multiplexed output beam. In order to reduce the footprint, emitters of the first and second emitter rows are disposed in an interleaved, staggered arrangement, and the second row of collimating and beam re-directing elements is disposed in a space between the first emitter row and the first row of collimating and beam re-directing elements.