Abstract: The principle and experimental technique of hiding optical instruments detection based on "Cat's eye" effect were described.The factors that influence the intensity of the reflection wave were analyzed both quantitatively and qualitatively with the method of ray tracing.Research results show that the incline and defocusing of reflection plane in optical instrument(such as telescope and camera) reduce the intensity of the "Cat's eye" reflection.For example,the ratio of the reflection energy of optical instrument and the pulse energy of scanning laser decreases from 3.3%(under the ideal reflection condition) to(0.03%)(for the defocusing) and 0.016%(for the incline) respectively,while the distance between the laser scanning setup and infrared camera is 1000m and the incidence angle of scanning laser is 0.3rad.