| 摘要 |
PROBLEM TO BE SOLVED: To always stably detect a focal point by improving variation in focal point detection value generated by phase in/phase out even in the case of photographing objects existing near and distant. SOLUTION: This focal point detecting device for detecting a focal point state of an imaging optical system includes: a photoelectric conversion means SNS having a line sensor array 112 outputting first and second image signals corresponding to first and second objects; and a computing means PRS for previously filtering the first and second image signals, obtaining an image shift amount of the first and second object images based on a change in evaluation amount and computing a defocus amount to the image shift amount, when the first and second image signals are sequentially relatively displaced in computing to compute the evaluation amount representing the degree of coincidence of the first and second image signals in each relatively displaced position. The above filtering is a processing applied to the first and second image signals using two, first and second digital filters which have a difference of 1 or less in group delay amount. COPYRIGHT: (C)2009,JPO&INPIT |
