Laser active detection technology based on cat’s eye effect is an effective detection and effect evaluation method for the implementation of strong laser interference on the UAV photoelectric system.Based on the theoretical analysis of optical detection system’s parameters,the calculation model of echo divergence angle and echo power caused by defocus is established.The influence factors of laser active detection technology are studied from the aspects of laser divergence angle,incidence angle and reflection angle.In order to determine whether it is valid,the influence factors of laser echo detection power are analyzed finely,and the effective angle range of laser interference is calculated under simulation conditions.