众所周知,凸透镜对光线具有会聚作用,凹透镜对光线具有发散作用。能否说,凡是使光线会聚的透镜一定是凸透镜,能使光线发散的透镜一定是凹透镜呢?或者说任何光线经凸透镜后一定是会聚光线,经凹透镜后一定是发散光线呢? 如图1所示,有一条会聚光线,不经过透镜时会聚 It is well known that a convex lens has a converging effect on light, and a concave lens has a divergent effect on light. Can we say that any lens that converges the light must be a convex lens, and the lens that can make the light divergent must be a concave lens? Or any light that passes through the convex lens must converge the light, and after the concave lens, it must be divergent light? Figure 1 Shows that there is a converging light that converges without going through the lens