adj.视觉的；光学的
The optical system of the eye stimulate cell of the retina. 眼睛的视觉系统刺激视网膜内的细胞。
A mirage is an optical illusion. 海市蜃楼是一种视错觉。
Microscopes and telescopes are optical instruments. 望远镜和显微镜是光学仪器。
My camera has an optical viewfinder. 我这个照相机装有光学取景器。
adj.大纲的(天气的)
