CN-122018221-A - Actuator for camera

Abstract

An actuator for a camera according to an embodiment of the present invention includes an OIS carrier that moves in a direction perpendicular to an optical axis direction, an AF carrier that supports the OIS carrier and moves in the optical axis direction together with the OIS carrier, a housing that supports the AF carrier, OIS magnets that are provided to the OIS carrier, and OIS coils that are provided to the housing so as to face the OIS magnets, wherein the OIS magnets have a height equal to or greater than twice a stroke, and the stroke is a movement distance of the AF carrier due to AF driving.

Inventors

• JIN XISHENG
• JIN YINZHU
• Tian Qixun

Assignees

• 磁化电子公司

Dates

Publication Date

20260512

Application Date

20250828

Priority Date

20241112

Claims (6)

1. 1. An actuator for a camera, comprising: An OIS carrier moving in a direction perpendicular to the optical axis direction; An AF carrier that supports the OIS carrier and moves in an optical axis direction together with the OIS carrier; a housing supporting the AF carrier; An OIS magnet disposed on the OIS carrier, and An OIS coil disposed in the housing so as to face the OIS magnet, The OIS magnet has a height of more than twice a stroke, which is a moving distance of the AF carrier caused by AF driving.
2. 2. The actuator for a camera according to claim 1, wherein, The center position of the OIS magnet is the same as or lower than the center position of the OIS coil with the AF carrier in the intermediate position of the stroke.
3. 3. The actuator for a camera according to claim 2, wherein, In the case where the AF carrier is located at the intermediate position of the stroke, a height deviation between the center position of the OIS magnet and the center position of the OIS coil is 30% or less of the stroke.
4. 4. The actuator for a camera according to claim 1, wherein, The device also comprises an OIS Hall sensor which detects the position of the OIS magnet and is arranged on the shell, The center position of the OIS magnet is the same as or lower than the center position of the OIS hall sensor with the AF carrier in the intermediate position of the stroke.
5. 5. The actuator for a camera according to claim 4, wherein, When the AF carrier is located at the intermediate position of the stroke, a height deviation between the center position of the OIS magnet and the center position of the OIS Hall sensor is 30% or less of the stroke.
6. 6. The actuator for a camera according to claim 1, wherein, Further comprises: an AF magnet provided to the AF carrier so as to face an AF coil provided to the housing; a yoke plate disposed on the housing and generating attraction with the AF magnet, and A ball disposed between the housing and the AF carrier, The yoke plate has a height greater than a sum of the height of the AF magnet and the stroke.

Description

Actuator for camera Technical Field The present invention relates to an actuator for a camera, and more particularly, to an actuator for a camera in which the position control and driving accuracy of OIS are further improved. Background With the development of hardware technology for image processing and the increase of user demands for image photographing and the like, functions of Auto Focus (AF), optical image stabilization (OIS, optical Image Stabilization) and the like have been applied to a stand-alone camera device, a camera module mounted in a mobile terminal such as a mobile phone, a smart phone and the like, and the like. The auto focus (auto focus) function is a function of generating a clear image in an image sensor (CMOS, CCD, or the like) provided at the rear end of a lens by linearly moving a carrier mounted with the lens or the like in the optical axis direction to adjust a focal length with an object. The optical image stabilization function is a function of, when shake of a lens or an image sensor occurs due to hand shake, adaptively moving a carrier on which the lens (or the image sensor) is mounted in a direction to compensate for the shake, thereby improving the sharpness of an image. One of the representative methods of realizing the auto-focusing function or OIS function is to provide a magnet (coil) on a moving body (carrier), and to provide a coil (magnet) on a fixed body (base, housing, or other form of carrier, etc.), and then to cause a driving force to be generated between the coil and the magnet, thereby moving the moving body in the optical axis direction or in a direction perpendicular to the optical axis. In the case of a device or actuator integrating the AF and OIS functions, a structure may be employed in which an AF carrier moving in the optical axis direction is used as a relatively fixed body, and the OIS carrier moves in a direction perpendicular to the optical axis (at least one of the X-axis and the Y-axis). The AF drive and the OIS drive are implemented in an independent manner, but in the case of implementing the AF drive by the above-described physical structure, the OIS carrier moves in the optical axis direction together with the AF carrier. Therefore, when the AF and OIS are driven together, the OIS carrier moves not only in the X-axis and/or Y-axis directions but also while having directivity including an optical axis direction (Z-axis direction) component. The positions of the OIS hall sensor that detects the position (X-axis direction) of the OIS magnet and the OIS coil that supplies the driving force to the OIS magnet are fixed. Therefore, if the AF carrier moves up and down (with reference to the optical axis direction) due to the driving of the AF as described above, the positional relationship between the OIS magnet and the OIS hall sensor and the positional relationship between the OIS magnet and the OIS coil irregularly change. If the OIS magnet has a movement characteristic including a Z-axis direction component, not only the accuracy of position detection in each direction for OIS is reduced, but also the accuracy of drive control based on this is reduced. Although it is also possible to try to solve this problem by applying a correction algorithm, it is necessary to apply a complex correction algorithm capable of reflecting the irregular movement characteristics, which increases the operation processing time and the like, and adversely affects the immediate responsiveness of OIS. Disclosure of Invention Technical problem to be solved The present invention has been made to solve the above-described problems in the background art, and an object of the present invention is to provide an optical (camera) actuator capable of further improving the accuracy of OIS driving by organically combining a physical layout structure for OIS configuration (OIS magnet, etc.) with a moving distance (stroke) or the like of AF carrier movement. Other objects and advantages of the present invention will be understood from the following description, and will be more clearly understood from the embodiments of the present invention. Furthermore, the objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. Means for solving the problems An actuator for a camera according to an embodiment of the present invention for achieving the above object may include an OIS carrier moving in a direction perpendicular to an optical axis direction, an AF carrier supporting the OIS carrier and moving in the optical axis direction together with the OIS carrier, a housing supporting the AF carrier, OIS magnets provided to the OIS carrier, and OIS coils provided to the housing in such a manner as to face the OIS magnets. In this case, the OIS magnet has a height of twice or more of a stroke, which is a moving distance of the AF carrier caused by AF driving. In addition, preferably,