He focused the sun's rays on a paper with a burning glass.

他用一面凸透把阳光聚焦纸上。

A physiotherapeutic apparatus for preventing and treating near sighted eye has a convex lens used as objective lens, lens cone, eyepiece, headgear and lens set.

一种防治近视眼的理疗器，它有作的凸透、筒、目，还有头套和透，它用于人们近距离上长间用眼眼上，可以使被视的像清楚、放大和变远。