When my son was born, the bedroom we put him in must be east facing, because the sun would just pour into his room early in the day and increase in brightness throughout the day.  At that time, we did not have any blinds or curtains in his room, a problem we needed to rectify promptly if there was to be any hope that he would nap.  I started to look into curtains to start with, and found many different varieties, from sheer to ridiculously thick, many choices, options and prices that ranged from very cheap to super expensive.