Real-time Optical Joint Transform Correlator System

An optical correlator is an optical information processing system for extracting the required information from many target information or for detecting specific information exists or not by using Fourier optical technologies. Optical correlators are widely used in optical image identification field. There are two kinds of optical correlator, the matched filter correlator (MFC) and the joint transform correlator (JTC). The JTC can identify the target very fast. Especially through the development of optoelectronic devices (such as SLM and CCD etc.), the real-time JTC has become possible.In this paper, I mainly completed the following works. First, the principle, characteristics, classification, application and development of optical correlator are introduced. Secondly, using the optoelectronic devices like electricity addressed liquid crystal spatial light modulator (LC-SLM) and CCD as well as some commonly used optical components, a set of optical electronic hybrid real-time optical JTC system is build. And using this system, simple targets like the same and different characters are identified, i.e. their joint power spectrum and correlation peak pictures are obtained. Finally, by using the MATLAB program the gray value distributions of the correlation peak pictures are obtained, and the quantitative experimental results are compared with each other.