Generally, it shouldn't make a difference what time of day your eyes are examined.However,according to the regular conduct and experience, the time varies because of different ages.For young children, the morning of the day or after a nap when they have a rest.During this time,they are willing to get an exam.For adults,you just come to get an exam as long as you are in good health and feel vigorous.That is because having a good health,means your eyes are also in goo d health.For seniors,the morning of the day will be the best time,that's because seniors always get up early,and they are in good health and feel sober in the morning.Under this condition,getting an eye exam must be successful. As i don't know what your age,you choose for yourself.I hope i can help you sincerely!