The first is a light green drop called Fluorescein.This tints your tears temporarily, allowing your doctor to determine the time it takes for your tears to dissipate after you blink.

• 第一种是浅绿色的荧光素，它能暂时对你的人造泪染色，使医生能够判定你眨眼后人造泪消失所需的时间。