Focus detection apparatus and control method thereof

A focus detection apparatus comprising:

• an auto focus sensor which receives reflected lights from an object at a plurality of light receiving sections and photoelectrically converts the received lights;
• a converting section which converts sensor data output from each of the light receiving sections into a digital signal;
• a memory section which stores each sensor data converted by the converting section;
• a plurality of arithmetic sections which concurrently execute a plurality of types of arithmetic operations which determines whether an object image is focused, a focal point of the reflected based each sensor data stored in the memory section;
• and
• a control section which adjusts determines whether the object image is focused, the focal point of the reflected based on an arithmetic operation result of each of the arithmetic sections.