Apparatus for detecting focusing status of taking lens

A focusing status detecting apparatus which detects a focusing status of a taking lens with respect to a two-dimensional image pickup device for image-output of a camera that obtains an image to be outputted, the focusing status detecting apparatus determining that the focusing status is one of front focus, rear focus, and in focus, the focusing status detecting apparatus comprising:

• a plurality of two dimensional image pickup devices for detecting the focusing status which detect the focusing status, the plurality of image pickup devices receiving subject light incident through the taking lens with different optical path lengths, a focusing evaluation value being obtained according to a high frequency component of each of images obtained by the plurality of image pickup devices for detecting the focusing status, the focusing status being determined according to the obtained focusing evaluation value,
• wherein an image pickup size of the plurality of image pickup devices for detecting the focusing status is smaller than an image pickup size of the image pickup device for image-output, and wherein of the digital signals of the images obtained by the image pickup devices for detecting focusing status only digital signals corresponding to pixels within a predetermined focus area are extracted, so that the focusing status is detected within a frame of the image smaller than the entire frame of the image to be outputted obtained by the image pickup device for image-output.