AUTOMATIC FOCUSING DEVICE FOR IMAGE PICKUP DEVICE

摘要

PURPOSE:To realize the automatic focusing device not requiring an exclusive component such as a range finder sensor. CONSTITUTION:When a change is in existence between a current picture in a 1st picture memory and a preceding picture in a 2nd picture memory through the comparison, an area subjected to change is specified. Discrete cosine transformation is executed to the located change area to calculate the total sum of high frequency components and a focus adjustment lens is moved so as to maximize the total sum of the high frequency components to adjust the focus automatically.