Drive controller for lens apparatus
AssigneeCanon Kabushiki Kaisha
InventorsNoboru Suzuki, Kazumasa Yoshikawa
Life of this patent
Estimating the term…
Abstract
A drive controller for a lens apparatus including a first lens unit which moves for changing magnification and a second lens unit which moves to prevent an image plane variation in response to the first lens unit moving to change the magnification. The drive controller includes a memory storing a plurality of tracking data corresponding to position data of the second lens unit, and a control unit for detecting a change in a focus state of the lens apparatus during the movement of the first lens unit and for changing one of the plurality of tracking data based on the detection result. The control unit stores a direction of the changing of the one tracking data and thereafter changes the one tracking data based on the stored direction.
Claims21
A drive controller for a lens apparatus including a first lens unit movable to change magnification and a second lens unit moving to prevent an image plane variation in response to the first lens unit moving to change the magnification, the drive controller comprising:
- a memory storing a plurality of tracking data corresponding to position data of the second lens unit;
- and
- a control unit detecting a change in a focus state of the lens apparatus during the movement of the first lens unit and changing at least one of the plurality of tracking data based on the detection,
- wherein the control unit performs a first control of storing a direction of the changing of the at least one of the plurality of tracking data and thereafter changing the at least one of the plurality of tracking data based on the stored direction,
- wherein, in the first control, the control unit changes the at least one of the plurality of tracking data in the stored direction responsive to the focus state changing towards an in-focus state, and
- wherein, in the first control, the control unit changes the at least one of the plurality of tracking data in a direction opposite to the stored direction responsive to the focus state changing towards an out-of-focus state.
A drive controller for a lens apparatus including a first lens unit movable to change magnification and a second lens unit moving to prevent an image plane variation in response to the first lens unit moving to change the magnification, the drive controller comprising:
- a control unit controlling driving the second lens unit;
- a memory storing tracking data corresponding to position data of the second lens unit;
- and
- a detecting unit detecting a movement speed of the first lens unit,
- wherein the control unit controls the driving of the second lens unit so as to search for a position nearer to an in-focus state of the lens apparatus when the movement speed is equal to or lower than a predetermined speed and controls the driving of the second lens unit by using the tracking data when the movement speed is higher than the predetermined speed.
A drive controller for a lens apparatus including a first lens unit movable to change magnification and a second lens unit moving to prevent an image plane variation in response to the first lens unit moving to change the magnification, the drive controller comprising:
- a control unit controlling driving the second lens unit;
- and
- a memory storing tracking data corresponding to position data of the second lens unit,
- wherein, when an evaluation value indicating a contrast state of a captured image is lower than a predetermined value, the control unit controls driving the second lens unit so as to search for a position corresponding to another evaluation value higher than the evaluation value, and
- wherein, when the evaluation value is equal to or higher than the predetermined value, the control unit controls driving the second lens unit based on the tracking data.
Dependencies are inferred from the claim text.