| 摘要 |
PURPOSE:To perform focusing position correction on the subject distance at the time of varying power by storing a position table for focusing groups in a memory and controlling the position of a focusing group on the basis of these data at the time of the variable magnification. CONSTITUTION:Since a focusing lens group 5 moves along its moving route in corresponding to the subject distance as a variable power lens group 2 moves forward or backward along its optical axis, a focused condition is maintained. Sets of a variable power position (x) and the position of a focusing lens Sij(x,V) and Sij(x,W) at the position (x) are stored in a memory as a numeral table to prefixed two different subject distances V and W. Therefore, the position Sij (a,U) of the focusing lens at which a focused condition (Point B) can be obtained can be found from the numeral of the table even when zooming is made to another variable power position (a) when the variable power position (b) and the position Sij (b,U) of the focusing lens group are stored after detection in a certain focused state (Point E).
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