One of the purposes of our work was the development of self-assembled photonic crystal for lowthreshold lasers. We have studied the spectral properties of two types of active PC matrix fabricated by horizontal self-assembly of dye doped polystyrene colloids in ambient conditions. We used nanospheres doped with Rhodamine-B and Fluored dyes with a diameter of 280 nm and 246 nm respectively, as determined by SEM observation and Bragg reflection analysis.