As some studies said, there has more than 750 kinds of chemical contains within cigarette smoke, most of them are toxic substance. It is bad for eyes. Amblyopic or weak sight will also be one of the affect which has been called toxic weak sight, the result will be view lessening, and discrepancies of red, green colors. The whole eyes sight will be affected by the smoking of toxic substance, how do you think about your night vision? Even the smoke itself may cause the infection of eyes or tears. You will feel foreign body on your eyes in the environment of smoking, no matter the active or passive smoking. Therefore, if you want to have a wonderful eye sight, you may get rid of smoking no matter in the daytime or at night.