Correlations are important in communications,memory and signal processing applications. Contrapose shortage of traditional correlator.A new implement of optical real-time correlator is introduced.Combined with Fourier theory and holography using the stimulate photon echoes(SPE) to perform correlation,physical phenomena of SPE is analysized.The principle of optical correlator is described.The implement of router using optical correlator is explained.The potentially value in optical fiber communications is mentioned.