Display that implements image displaying and light reception concurrently or alternately

A display device that implements image displaying and light reception alternately, the display device comprising:

• a plurality of display elements arranged in a matrix;
• a plurality of light-receiving elements disposed adjacent to the plurality of display elements, the display elements and the light-receiving elements are offered by a common element that implements displaying and light reception alternately;
• a position detector;
• a processor;
• a backlight disposed on a backside of a surface on which the display elements are arranged;
• and
• a memory device storing instructions which when executed by the processor, cause the processor to operate with the plurality of display elements, the plurality of light-receiving elements, the position detector, and the backlight to:
• (a) determine a position of contact or proximity to a display plane based on a light reception signal arising from light reception;
• (b) in a predetermined state, determine whether a presence of contact or proximity occurs;
• (c) in response to the presence of contact or proximity, shift a displaying state and a position detection state from a low power consumption mode to a normal operation mode;
• (d) in the normal operation mode:
• implement displaying of images according to a first cycle,
• implement detection of contact or proximity based on a light reception signal arising from light reception by all of the plurality of light-receiving elements according to the first cycle, and
• continuously cycle the backlight between an on-state and an off-state,
• wherein detection of contact or proximity in the normal operation mode occurs by detecting the difference between the data of light reception when the backlight is in the on-state and when the backlight is in the off-state;
• and
• (e) in the low power consumption mode:
• stop displaying of images,
• implement detection of contact or proximity based on a light reception signal arising from light reception by the plurality of light-receiving elements with a second cycle longer than the first cycle of detection of contact or proximity in the normal operation mode, and only based on a light reception signal arising from light reception by the light-receiving element in a specific area on the display plane smaller than that of the normal operation mode, and
• maintain the backlight at the off-state,
• wherein detection of contact or proximity in the low power consumption mode occurs by detecting only changes of the input state of external light with the backlight at the off-state.