The cat eye effect can be used for active detection of electro-optical equipment.In the face of the complexity of the environment,it is particularly important to seek ways to improve the effectiveness of active detection.The analysis model of cat eye effect was established,and the influence mechanism of the echo on the cat eye effect was analyzed.The incident angle,the defocusing amount and other parameters were used to derive average illumination expression of the echo energy.The factors that restrict the ability of active detection were analyzed so as to seek a method to improve the detection probability.Finally,the simulation is carried out by using FRED.Results show that the defocusing results in echo divergence angle which will reduce the echo energy;the tiny incident angle without changing the effective optical aperture can reduce the echo divergence angle;the detection of laser wavelength and divergence angle can compensate for the inherent defocusing amount of cat eye system so as to improve the detection ability;the simulation results have proved the conclusion.