convex-concave lens是什么意思

用法例句

The images can be used to measure the refractive index of thin convex-concave lens and the radius of curvature of its fore and rear surfaces.

介绍了薄透镜焦距测定中观察到的薄凸凹透镜对物的球面反射成像及折—反—折成像，指出利用这一现象可较好地测定薄凸凹透镜的折射率及前后表面的曲率半径。