My prescription is within the +2 to -7 prescription correction range, why do words or images still seem a little blurry?
There are several reasons why your lens power (measured in diopters (D)) can fall within the range yet the screen still seems a little blurry after focusing. First, it could be some time since you last had your eye exams and your eyes may have adjusted. Someone near the max ranges of the +2 to -7 could be the most affected. Second, Moon does not correct for astigmatism. So, if you have a number under the Cylinder column for a prescription that means you have an astigmatism and it may cause the edges to be blurry and/or affect your ability to focus your Moon. Third, if it is mostly the words that are blurry you might just be affected by presbyopia which is the natural inability to see sharp objects up close as we age.