when we come out of a dark room what changes take place in the size of The Pupil and why

         Dear student
When we come out of a dark room our eyes feel a glaring affect this is due to the reason that in dark room the pupil is large so when we come out in bright light,a large amount of light enters our eyes and we feel glare but after some time,the pupil contract and we become able to able to see clearly as less light enters our eyes now
             Regards