System and method for testing solar cells is provided. The system includes a first light source configured to generate a first optical beam; a second light source configured to generate a second optical beam; a reflector for each light source, configured to collimate and direct each of the first optical beam and the second optical beam; a spectral filter assembly associated with each of the first light source and the second light source, the spectral filter assembly configured to (a) receive the first optical beam and the second optical beam (b) split each of the first optical beam and the second optical beam into “N” smaller optical beams, and (c) filter the “N” smaller optical beams; a re-imaging assembly for each spectral filter assembly configured to re-image the smaller “N” optical beam at a dichroic mirror that receives one or more N beams.