An antimicrobial composition with synergistic biocidal activity is described which comprises at least one antimicrobial polymeric biguanide and at least one antimicrobial vicinal diol, said vicinal diol comprises at least one monoalkyl glycol, monoalkyl glycerol, or monoacyl glycerol, to diminish or eliminate biofilm communities. The metric values for a parameter set are determined based on signals generated by the sensors when that therapy parameter set was in use. In a laser projection system, the separation distance between reflective flakes may be at least twice the coherence length of the laser light.