| 摘要 |
PURPOSE:To detect a focusing state with simple configuration and processing. CONSTITUTION:Picture data obtained by reading a focusing checking chart having a pattern on which white level areas and black level areas are arranged alternately by an image sensor are inputted to a latch 42 and a level difference detection circuit 43 at every picture element. The level difference detection circuit 43 obtains the level difference of picture data between adjacent picture elements over one line and the maximum value of the level difference values is obtained by a maximum value deciding circuit 44. Then a decision circuit 45 compares the maximum value obtained by the maximum value deciding circuit 44 with a reference value DR set in advance to decide the focusing state. |
