JP-7855446-B2 - Optical unit with image stabilization function

JP7855446B2JP 7855446 B2JP7855446 B2JP 7855446B2JP-7855446-B2

Inventors

笠原章吾
須江猛

Assignees

ニデックインスツルメンツ株式会社

Dates

Publication Date: 20260508
Application Date: 20220720

Claims (4)

The device comprises a movable body having a camera module, a first intermediate member that rotatably holds the movable body, a second intermediate member that rotatably holds the first intermediate member, a fixed body that rotatably holds the second intermediate member, a first magnetic drive mechanism and a second magnetic drive mechanism for rotating the movable body relative to the fixed body so that the optical axis of the camera module is tilted in an arbitrary direction, a third magnetic drive mechanism for rotating the movable body relative to the fixed body with the optical axis of the camera module as the pivot point, a first magnetic sensor and a second magnetic sensor for detecting the rotational position of the movable body relative to the fixed body, and a flat first magnetic plate and a second magnetic plate for biasing the movable body toward a reference position of the movable body, which is the position of the movable body when the optical axis of the camera module is facing a predetermined reference direction. When the movable body is positioned at the reference position, a predetermined direction perpendicular to the optical axis of the camera module is defined as the first optical axis orthogonal direction, and when the movable body is positioned at the reference position, a direction perpendicular to both the optical axis of the camera module and the first optical axis orthogonal direction is defined as the second optical axis orthogonal direction. The first magnetic drive mechanism comprises a first drive magnet and a first drive coil arranged opposite to each other in a direction perpendicular to the first optical axis, and rotates the movable body relative to the fixed body with a second rotation axis parallel to the direction perpendicular to the second optical axis as the rotation center. The second magnetic drive mechanism comprises a second drive magnet and a second drive coil arranged opposite to each other in a direction perpendicular to the second optical axis, and rotates the movable body relative to the fixed body with a first rotation axis parallel to the direction perpendicular to the first optical axis as the rotation center. The third magnetic drive mechanism comprises a third drive magnet and a third drive coil arranged opposite to each other in a direction perpendicular to the first optical axis, and a fourth drive magnet and a fourth drive coil arranged opposite to each other in a direction perpendicular to the second optical axis. The first magnetic sensor and the first magnetic plate are arranged opposite the first driving magnet in a direction perpendicular to the first optical axis, The second magnetic sensor and the second magnetic plate are arranged opposite the second driving magnet in a direction perpendicular to the second optical axis. The fixed body includes an intermediate member holding portion that rotatably holds the second intermediate member, When the movable body is positioned at the reference position, the outer shape of the intermediate member holder, when viewed from the optical axis direction, which is the direction of the optical axis of the camera module, is square or rectangular. The first magnetic drive mechanism, the first magnetic sensor, the first magnetic plate, the third drive magnet, and the third drive coil are arranged along one side of the intermediate member holding portion that is parallel to the direction perpendicular to the second optical axis, among the four sides of the intermediate member holding portion that have a square or rectangular shape when viewed from the optical axis direction when the movable body is positioned at the reference position. The second magnetic drive mechanism, the second magnetic sensor, the second magnetic plate, the fourth drive magnet, and the fourth drive coil are arranged along one of the four sides of the intermediate member holder that is parallel to the direction perpendicular to the first optical axis. A portion of the first drive magnet and a portion of the first drive coil are arranged on the first pivot axis. The third drive magnet and the third drive coil are arranged on one side of the first magnetic drive mechanism in a direction perpendicular to the second optical axis. The center of the first drive magnet and the center of the first drive coil are positioned offset from the first rotation axis to the other side in the direction perpendicular to the second optical axis. The center of the first magnetic sensor and the center of the first magnetic plate are arranged on the first rotation axis, A portion of the second drive magnet and a portion of the second drive coil are arranged on the second pivot axis. The fourth drive magnet and the fourth drive coil are arranged on one side of the second magnetic drive mechanism in a direction perpendicular to the first optical axis. The center of the second drive magnet and the center of the second drive coil are positioned offset from the second rotation axis to the other side in the direction perpendicular to the first optical axis. An optical unit with a vibration correction function, characterized in that the center of the second magnetic sensor and the center of the second magnetic plate are arranged on the second rotation axis.
If we define the direction perpendicular to the first optical axis as the first direction side on which the first magnetic drive mechanism is positioned relative to the second magnetic drive mechanism, the opposite side of the first direction side as the second direction side, the direction perpendicular to the second optical axis as the third direction side on which the second magnetic drive mechanism is positioned relative to the first magnetic drive mechanism, and the opposite side of the third direction side as the fourth direction side, The third drive magnet and the third drive coil are arranged on the third direction side of the first magnetic drive mechanism. The fourth drive magnet and the fourth drive coil are arranged on the first direction side of the second magnetic drive mechanism. The center of the first drive magnet and the center of the first drive coil are offset from the first rotation axis toward the fourth direction, The optical unit with vibration correction function according to claim 1, characterized in that the center of the second drive magnet and the center of the second drive coil are offset from the second rotation axis toward the second direction.
The system comprises a third magnetic sensor positioned opposite the third driving magnet in a direction perpendicular to the first optical axis, a fourth magnetic sensor positioned opposite the fourth driving magnet in a direction perpendicular to the second optical axis, and a control unit to which the third magnetic sensor and the fourth magnetic sensor are electrically connected. The optical unit with shake correction function according to claim 2, characterized in that the control unit detects the rotational position of the movable body relative to the fixed body with the optical axis of the camera module as the pivot point, based on the output signal of the third magnetic sensor and the output signal of the fourth magnetic sensor.
The third driving magnet is composed of two magnetized parts polarized in a direction perpendicular to the second optical axis, The fourth drive magnet is composed of two magnetized parts polarized in a direction perpendicular to the first optical axis, The optical unit with vibration correction function according to claim 2 or 3, characterized in that the magnetic pole on the third direction side of the third drive magnet and the magnetic pole on the first direction side of the fourth drive magnet are the same magnetic pole.

Description

This invention relates to an optical unit with image stabilization function for use in portable devices and the like. Conventionally, optical units with image stabilization functions for use in portable devices and the like are known (see, for example, Patent Document 1). The optical unit with image stabilization function described in Patent Document 1 comprises an optical unit body housed in a cover. The optical unit body includes an imaging module having a lens and an image sensor. Furthermore, the optical unit body comprises a movable body having the imaging module, a rotation support mechanism supporting the movable body so that it can rotate around the optical axis of the lens, a gimbal mechanism supporting the rotation support mechanism so that it can rotate around a first axis perpendicular to the optical axis and around a second axis perpendicular to both the optical axis and the first axis, and a fixed body supporting the movable body via the gimbal mechanism and the rotation support mechanism. In the optical unit with shake correction function described in Patent Document 1, the movable body is supported by a fixed body so that it can rotate around the optical axis, the first axis, and the second axis. The optical unit body includes a first shake correction magnetic drive mechanism that generates a driving force around the X axis tilted 45° around the optical axis with respect to the first and second axes, a second shake correction magnetic drive mechanism that generates a driving force around the Y axis perpendicular to the optical axis and the X axis, and a rolling correction magnetic drive mechanism that rotates the movable body around the optical axis. In the optical unit with shake correction function described in Patent Document 1, the external shape of the fixed body when viewed from the optical axis direction is square. Specifically, the external shape of the fixed body when viewed from the optical axis direction is square, having two sides parallel to the X-axis direction and two sides parallel to the Y-axis direction. In this optical unit with shake correction function, the first shake correction magnetic drive mechanism is arranged along one of the two sides of the fixed body parallel to the X-axis direction, the rolling correction magnetic drive mechanism is arranged along the other side of the fixed body parallel to the X-axis direction, and the second shake correction magnetic drive mechanism is arranged along one of the two sides of the fixed body parallel to the Y-axis direction. In other words, in this optical unit with shake correction function, the first shake correction magnetic drive mechanism, the second shake correction magnetic drive mechanism, and the rolling correction magnetic drive mechanism are arranged along three sides of the fixed body, which has a square external shape when viewed from the optical axis direction. Japanese Patent Publication No. 2021-28655 This is a perspective view of an optical unit with shake correction function according to an embodiment of the present invention.Figure 1 is a plan view of the optical unit with shake correction function.Figure 1 is an exploded perspective view of the optical unit with shake correction function.Figure 3 is an exploded perspective view of the second intermediate member and the second support point, etc.Figure 4 is an exploded perspective view of the holder, first intermediate member, and first support point shown.This is a plan view showing the holder, first magnetic drive mechanism, second magnetic drive mechanism, and third magnetic drive mechanism shown in Figure 2.Figure 6 is a rear view showing the holder, first magnetic drive mechanism, first magnetic sensor, third magnetic sensor, first magnetic plate, third drive magnet, and third drive coil from the E-E direction.Figure 6 is a side view showing the second magnetic drive mechanism, second magnetic sensor, fourth magnetic sensor, second magnetic plate, fourth drive magnet, and fourth drive coil from the F-F direction.Figure 2 is a plan view illustrating the arrangement of the third drive magnet, the fourth drive magnet, the third drive coil, the fourth drive coil, the third magnetic sensor, and the fourth magnetic sensor when the movable body shown rotates relative to the fixed body with the optical axis of the camera module as the pivot point.Figure 9 is a graph illustrating an example of the output signals of the third and fourth magnetic sensors. The embodiments of the present invention will be described below with reference to the drawings. (Overall configuration of the optical unit with image stabilization function) Figure 1 is a perspective view of an optical unit 1 with shake correction function according to an embodiment of the present invention. Figure 2 is a plan view of the optical unit 1 with shake correction function shown in Figure 1. Figure 3 is an exploded perspective view of the optical unit 1 with shake correction function shown in Figure 1