| 摘要 |
PROBLEM TO BE SOLVED: To perform effective autofocus control highly precisely without deteriorating focusing precision as in the past, by considering inherent characteristics of a piezoelectric element. SOLUTION: A sensor module comprises: a lens part 1 for concentrating light of a photographic subject; an imaging device 2 on which an image of the light of a photographic subject is formed by the lens part 1; a drive part 3 for driving the piezoelectric element 31 so as to move the lens part 1 closer to or away from the imaging device 2 in one direction or in the reverse direction; and autofocus control means 50 for moving the lens part 1 in a predetermined direction from a reference point to a plurality of predetermined points consecutively by the drive part 3, calculating a focal point evaluation value, which increases as the lens becomes closer to the focal point, from image information based on an image signal from the imaging device 2 for each of the points, obtaining a peak position that corresponds to a peak value of each calculated focal point evaluation value, and subsequently, returning the lens part 1 temporarily to the reference point, and move the lens part 1 in the predetermined direction from the reference point to which the lens part is returned, to the peak position. COPYRIGHT: (C)2009,JPO&INPIT |
