Research on the mechanism of reflection characteristics of laser irradiation on cat eye optical lens
激光辐照猫眼光学镜头时的反射特性机理研究

Using the theory of matrix optics and expanding the aperture function into a sum of finite complex Gaussian functions, this paper theoretically deduces the mechanism of cat eye effect generated by laser irradiation on the cat eye optical lens and analyzes the reflection law of cat eye effect through numerical computation. Then an experiment is operated to validate the cat eye effect by making 532nm laser irradiate on an optical zoom lens whose focusis ranged between 12 and 72mm. By using the above method, the law governing the variation of laser reflection characteristics with the parameters of the transmitting laser beam and the cat eye optical lens, including aperture, focus and focal shift etc, is established. The study reveals that the reflection characteristics of cat eye effect are intimately correlated with the parameters of the cat eye optical lens and transmitting laser beam, furthermore, the characteristics would change obviously when there is a large change in the distance between the waist of the incident beam and the cat eye optical lens. In particular, a reasonable choice of the positive focal shift would result in a higher peak intensity at the return place than that of no focal shift, when the distance between the waist of the incident beam and the cat eye optical lens varies, whereas the former conclusion based on geometry optics was that the highest peak intensity could be obtained when the optical lens has no focal shift.