| 摘要 |
PURPOSE:To shorten time required for correlational operation by comparing the sizes of correlational operation values and moving an image pickup optical system in each prescribed distance when the optical system is in a non-focused state. CONSTITUTION:A pair of analog electric signals corresponding to the distribution of light intensity of a pair of optical images are non-destructively outputted from a sensor means 32 while being delayed in each picture element unit at a prescribed period and correlationally operated by a correlational operation means and a correlational operation value H(0) when a relative moving distance lis l=0 and a correlational operation value (1) at the time of l=1 are sequentially outputted. When the image pickup optical system is in the non-focused state, the image pickup optical system is moved in each prescribed variable (e.g. a unit moving distance) while comparing the sizes of the correlational operation values H(0), H(1) obtained when the relative moving distance is l=0 and l=1. Consequently, time required for correlational operation can be shortened. |
