| 摘要 |
PURPOSE:To provide a focus controller where the influence of noise regarding an AC component having a low illuminance characteristic is evaded and an integrated value to which the change of an AC component having high illuminance and low contrast characteristic is faithfully reflected is generated. CONSTITUTION:A subtraction ratio changing means 20 judges the illuminance on an AC component S1 by referring to a parameter P. The subtraction ratio changing means 20 sets the subtraction ratio of a subtraction circuit 19 to a first subtraction ratio when it judges that the illuminance is low illuminance. Further, the subtraction ratio changing means 20 sets the subtraction ratio of the subtraction circuit 19 to a second subtraction ratio when it judges that the illuminance is high illuminance and low contrast. The subtraction ratio changing means 20 sets time subtraction ratio of the subtraction circuit 19 to a third subtraction ratio when it performs a judgment other than low illutminance, high illuminance and low contrast. As a result, a proper integrated value according to the illuminance can be provided. |
