| 摘要 |
PURPOSE:To enable an optical system to select an optimum focusing state by providing a front group lenses of one or more groups and an output means which can transmit the information peculiar to the front group lenses outputted from the output means to a camera main body on an exchangeable lens side. CONSTITUTION:Rear group lenses 13a and 13b containing a lens for inner focusing and a driving device for the lens for inner focusing are provided on a camera main body 1 side. Then front groups lenses 20 of one or more groups and an output means which can transmit the information peculiar to the front group lenses 20 outputted by the output means are provided on an exchangeable lens side. At the same time, control means 6 and 7 which perform control in accordance with the peculiar information outputted from the output means are provided on the camera main body 1 side. Therefore, photographing can be performed by selecting the exchangeable lens provided with a lens for front focusing and, when the exchangeable lens has a zooming function especially, focusing can be performed with the minimum variation in aberration. |
