an electronic apparatus includes : a luminance adjustable display module ; an illuminance sensor configured to detect illuminance around the electronic apparatus ; and a controller configured to : read the illuminance from the illuminance sensor ; determine luminance corresponding to the illuminance ; control the luminance adjustable display module to set luminance to the determined luminance ; and set a waiting time based on the determined luminance , the waiting time being a time to a next time point of illuminance reading and luminance control . the controller is configured to set the waiting time short when the determined luminance is high and to set the waiting time long when the determined luminance is low .