| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic focusing device capable of performing focusing operation at high speed with simple constitution. SOLUTION: A digital camera to which this automatic focusing device is applied is equipped with a lens system for forming an object image and including an auxiliary lens 101B having different refractive indexes in two directions orthogonal to an optical axis direction and orthogonal to each other, a color image sensor 103 where an AF area is set at least at one part of an imaging area and which converts the object image formed by the lens system into image data, a distance and direction calculating part 111 obtaining dot image distribution showing the blur characteristic of the image data of the AF area and estimating the direction of a focusing point and a distance to the focusing point based on the size and the length-and-width difference of the dot image, and a focusing driving device 112 determining whether or not a focusing state is attained and moving the lens system or the sensor 103 the estimated distance to the focusing point in the estimated direction of the focusing point when it determines that the focusing state is not attained. |
