| 摘要 |
An imaging apparatus includes an anti-shake system provided with a first guide portion supporting a movable frame, supporting a front lens element, at three support points to allow the movable frame to move relative to a base member, which supports a reflector element; a second guide portion which allows the movable frame to move, relative to the base member, in a linear direction and rotate; a limit portion defining a range of movement thereof; and two actuators. The rotational axis of the second guide portion is positioned outside a support intra-region defined by three sides connecting the three support points; a point of intersection between two planes passing through the centers of the actuators and extending in the intersecting driving-force directions of the actuators is positioned inside the support intra-region; and the limit portion and the center of gravity of the movable frame are positioned inside the support intra-region. |
| 主权项 |
1. An imaging apparatus, comprising:
a front lens group which constitutes part of an imaging optical system of said imaging apparatus and is provided at a fixed position with respect to an optical axis direction, wherein said front lens group includes at least one front lens element and a reflector element, in that order from an object side, and wherein light rays exiting from said front lens element along a first optical axis are reflected by said reflector element to travel along a second optical axis that is nonparallel to said first optical axis; at least one rear lens group which constitutes another part of said imaging optical system and is provided closer to an image plane than said front lens group; and an anti-shake system which drives said front lens element along a plane orthogonal to said first optical axis, in response to vibrations applied to said imaging optical system, to reduce image shake on said image plane, wherein said anti-shake system comprises: a base member which supports at least said reflector element of said front lens group; a movable frame which supports said front lens element of said front lens group; a first guide portion which supports said movable frame at at least three support points so as to allow said movable frame to move relative to said base member along said plane orthogonal to said first optical axis and restricts movement of said movable frame relative to said base member in said first optical axis direction; a second guide portion which guides said movable frame relative to said base member so as to allow said movable frame to move back and forth in a predetermined linear direction and rotate about a predetermined rotational axis; a limit portion which defines a range of movement of said movable frame relative to said base member in said plane orthogonal to said first optical axis; and a first actuator and a second actuator which generate a driving force for moving said movable frame in a first direction and in a second direction, respectively, said first direction and said second direction intersecting each other in said plane orthogonal to said first optical axis, wherein said rotational axis of said second guide portion is positioned outside a support intra-region which is defined by three sides connecting said three support points, as viewed along said first optical axis; wherein a point of intersection between a first plane, which is parallel to said first optical axis and extends in said first direction of said driving force of said first actuator while passing through a center of said first actuator, and a second plane, which is parallel to said first optical axis and extends in said second direction of said driving force of said second actuator while passing through a center of said second actuator, is positioned inside said support intra-region, as viewed along said first optical axis; wherein said limit portion is positioned inside said support intra-region, as viewed along said first optical axis; and wherein a center of gravity of said movable frame is positioned inside said support intra-region, as viewed along said first optical axis. |
