Generally speaking, an eye exam does not cause harm to your eyes. However, if the doctor applied something like eye drops to your eyes before the exam, you might have some problems like blurred vision. Or it might because you focused on the diagram too much. Anyway, it is ok if the situation does not last.
Well, generally speaking, it is normal to have blurred vision after you have eye exam. and according to some experts, it can be because of the eye strain you have got when you are in the eye exam. first, you should know that when you have an eye exam, it will make your eyes focus on the points for a long time. in that way, the doctor can make the light go through your eyes to check it. in the end, it can lead eye strain and eye pressure. As we know that eye pressure can lead to a lot of eye problems such as dry eyes, even blurred eyes. and in common, maybe it can be fine in a few days. So you should not worry about it.
Before you do the eye exam, you will be accepted to use the eye drops. Your blurry vision after the eye exam may be caused by your original eyes diseases that you have ignored. You'd better see the eye exam to find that whether you have the eyes problems. If you do, you'd better accept the treatment as soon as possible.