A light source system includes a first light emitter configured to emit a first light with a first color band in a first time interval of a time period, a second light emitter configured to emit a second light with a second color band in a second time interval of the time period rather than in the rest of the time period other than the second time interval, and a light guide disposed downstream from the first light emitter and the second light emitter. The first time interval and the second time interval overlap in an overlapping time interval. The first light emitter and the second light emitter synchronously emit the first light and the second light in the overlapping time interval to form a combined light beam in the light guide. The light with the second color band is dominant of the combined light beam.