Abstract: In an optical system, “cat eye effect” can be modeled as a focus lens system. Based on the model and Fourier transform, when a system has some optoelectrical devices and illuminated by one laser beam, the laser beam will be reflected from the system along incident direction as a result of “cat eye effect”. The experimental proof is made by the detection of laser power backscattered from the optosensitive material, such as CCD. The experiments show that “cat eye effect” surely exists in the optoelectrical detectors. With “cat eye effect”, the target with optoelectrial detectors could be detected and classified. In the experiment, the ratio of the laser power reflected from the CCD detector surface and the input laser power is about 4%. Though the experiments are simple and its d