Digital camera and method of controlling the same

A digital camera comprising:

• a flash unit including a light source, the flash unit configured to emit light to illuminate a subject using a preliminary light emission operation followed by a main light emission operation;
• an image sensor including a pixel array arranged along a plurality of lines, the image sensor configured to convert an image of the subject into an electrical signal by reading an image frame corresponding to one screen using the pixel array, to perform the reading operation in units of frames in response to a vertical synchronization signal, and to perform the reading operation in units of lines in response to a horizontal synchronization signal;
• and
• a digital signal processor communicatively coupled with the flash unit and the image sensor, the digital signal processor configured to control the light emitting operation of the flash unit to start the preliminary light emission operation at a synchronization pulse of the vertical synchronization signal and end the preliminary light emission operation at a next synchronization pulse.

A method of controlling a digital camera that includes a flash unit that provides a light source for photographing, and an image sensor that includes a pixel array arranged along a plurality of lines and that is configured to convert an image of the subject into an electrical signal by reading an image frame corresponding to one screen, the method comprising:

• starting a preliminary light emission operation of a flash unit;
• reading an image frame corresponding to one screen using an image sensor while maintaining the preliminary light emission operation;
• ending the preliminary light emission operation;
• calculating an amount of light required for a main light emission operation by analyzing a luminance signal of the image frame;
• and
• performing a main light emission operation according to the calculated amount of light.