Focus adjustment unit and camera system

A camera system, comprising a camera body having an image sensor, and an interchangeable lens removably attached to the camera body, wherein:

• the interchangeable lens comprises:
• a photographing optical system, including a focusing lens capable of moving in the optical axis direction and capable of adjusting a focused state, for introducing subject light to the image sensor;
• a lens communication section for carrying out communication with the camera body;
• and
• a lens control section for controlling communication operations with the camera body by the lens communication section, and controlling movement of the focusing lens, and
• the camera body comprises:
• a body communication section for carrying out communication with the interchangeable lens;
• a body control section for instructing movement of the focusing lens to the lens control section, and carrying out focus adjustment by executing imaging operations using the image sensor and controlling scan operations for detecting position of the focusing lens at which a peak of image contrast occurs, based on a plurality of items of imaged data output by the image sensor;
• a continuous shooting speed setting section for setting a speed for continuously executing exposure operations for shooting using the image sensor;
• and
• a limit time setting section for setting an effective limit time for carrying out the scan operation in accordance with a continuous shooting speed that has been set by the continuous shooting speed setting section, wherein
• the body control section controls the scan operation so that the limit time that has been set up by the limit time setting section is not exceeded.

A focus adjustment unit, for carrying out focus adjustment of a photographing optical system that concentrates light from a subject, including a focusing lens capable of movement in the optical axis direction, comprising:

• a lens drive section for driving the focusing lens;
• an image sensor for acquiring imaged data for a subject image that has been concentrated by the photographing optical system;
• and
• a control section for executing imaging operations using the image sensor by causing movement of the focusing lens, and carrying out a scan operation for detecting position of the focusing lens at which a peak of image contrast occurs, based on a plurality of items of imaged data output by the image sensor,
• wherein the control section stores a minimum value for a number of frames of imaged data required in order to detect a peak of contrast using the scan operation, and carries out scan operation in accordance with a number of frames being the minimum value or more.