Well, in some cases, it is possible to have blurry vision if you wear sleep masks. First, you should know that by wearing sleep masks, your eye pressure will be high. And then it will just affect your eyes, leading to eye strain and blurry vision. On the other hand, I have to say that, it also may be because of the infection. As we know that blurry vision is also can be caused by the bacteria, and other allergies, when your eyes are infected by some viruses, you can get eye infection. In that way, it is likely to have blurry vision too. so just have an eye exam to check the real reason.