Driving apparatus, and lens apparatus and image pickup apparatus including the same

An image pickup apparatus, comprising:

• a lens apparatus comprising a driving apparatus for driving a movable optical member, the driving apparatus being removably attached to a lens barrel, the driving apparatus comprising:
• a rotary absolute position detector detecting a position of the movable optical member, the rotary absolute position detector outputting an output value having a unique value with respect to a rotation angle within a range of a single rotation, and the output value having a point of discontinuity at which the output value is discontinuous every single rotation;
• and
• a controller performing boundary processing that handles the output value, corresponding to a driving range of the movable optical member, of the rotary absolute position detector having the point of discontinuity as a continuous value;
• and
• an imaging device connectable to the lens apparatus so as to take an object image.