No, garlic won't improve your Vision.
Though garlic can prevent many diseases, it is not good for eyes. If you eat lots of garlic for a longtime, it have bad effect to your eyes. If you often eat garlic, in your ages of 50,or 60, you will feel vision blur, vision decreased and memory loss etc. So, wearing garlic not improve your vision, but do harm to your vision in latter of your life.
Yes, it could. Garlic is a kind of vegetable, which has different mineral, such as Ca, Mg, Na, Fe. It can inhibit bacterial because of its cell infiltration ability. Garlic is good for people's health, especially heart disease. And mainly vitamin A food, such as carrot, pumpkin, tomato can keep the eye healthy as well as garlic. However, it would be harmful to eye vision if you overeat garlic. Hence, the adult normally eat 5g of garlic per day. On the other side, it would cause smelly after eating garlic. It's useful to drink some milk, a cup of coffee or tea to get rid of it as well as chawing gun.
Garlic is nourishing, garlic can prevent a lot of diseases, it can disinfect, prevent tumour and cancer, and can also protect liver. In theory, too much garlic is bad too your eyes. That is because garlicis spicy, it gets blood trouble, and blood can nourish the liver, eyes' function is root in liver,
Garlic has some role in prevention of many diseases, however, if people eat it for a long-term, especially those people with eye disease, they will have adverse effects, when they reach their 50s or 60s, they will gradually feel that they can not see things clear, and their vision will decrease. So garlic can not improve your vision.