Well, generally speaking, vitamin a deficiency can not cause blindness. But on the other hand, if you suffer vitamin a deficiency, it can just cause many eye problems; for example, vitamin a deficiency can lead to dry eyes. So just be careful about the vitamin a deficiency, or it can be dangerous to have dry eyes. According to some researches, if you do not intake enough vitamin A, you may also experience problems with dry eye. To treat it, you can take some foods which are rich in vitamins such as the fishes and some other vegetables. Also, your eyes will just suffer watery eyes too. So just be careful about it.
Ok, from what i can see, it seems that you concern a lot about your eye health,which is good for you. So, it is true that a lack of vitamin a could give rise to a lot of problems, such as decreased vision, eye strain, nyctalopia, and some other serious problems, etc. Because, vitamin a is a must for our eye health, which contains many kinds of nutrition. So you have to pay attention to your vitamin intake, which is vital for your eye health.