Method of acquiring outside luminance using camera sensor and electronic device applying the method

An electronic device comprising:

• a housing;
• a display viewable via a front surface of the housing and configured to display a screen;
• a camera sensor disposed proximate at least a portion of the front surface of the housing and configured to measure an external illuminance;
• a processor operationally connected to the display and the camera sensor;
• and
• a memory operationally connected to the processor,
• wherein the memory is configured to store instructions that, when executed, are configured to cause the processor to control the electronic device to:
• detect a turn-on event of the display;
• turn on the camera sensor to acquire the external illuminance via the camera sensor at a time point when the display is turned on;
• acquire information related to the external illuminance during an acquisition interval through the camera sensor, wherein the acquisition interval corresponds to one frame interval;
• turn off the camera sensor after acquiring the information during the acquisition interval;
• determine the external illuminance based on the information acquired during the one frame interval;
• and
• control a luminance of the display based on the external illuminance.