For some people with astigmatism this is a worst case scenario. As you try and read a light font on a dark background in a dark room, the pupil opens up, lettin

For some people with astigmatism this is a worst case scenario. As you try and read a light font on a dark background in a dark room, the pupil opens up, letting more light in, however opening up the pupil this way exacerbates the effect of the deformed cornea.