Lens module

Abstract

Provided is a lens module having a lens drive mechanism having a simple structure which can stabilize the shift speed of an optical lens. The lens module has a structure wherein a lens holder (6), on which a moving body (5) that can be attracted to a magnet (4) is mounted and the optical lens not shown in a figure is to be mounted, is mounted on a housing (7) by using a guide pin (8), one side of a piezoelectric ceramic element (3) in a displacement generating direction (longitudinal direction) is bonded to the magnet (4), the other side is bonded to the housing (7), and the moving body (5) and the magnet (4) are attracted by a magnetic force. The lens holder (6) supporting the moving body (5) is supported by the guide pin (8) in a manner that the lens holder can be shifted. A lens driving mechanism has the magnetization direction of the magnet (4) in the radius direction of the optical lens by permitting the magnetization direction to substantially orthogonally intersect with the optical axis direction of the optical lens. The lens module is provided with the lens drive mechanism which vibrates the magnet (4) by vibration generated by a piezoelectric ceramic element (3), and shifts the lens holder (6) along an optical axis direction by driving the moving body (5) by using the vibration of the magnet (4) as a driving force.

Description

technical field [0001] The present invention is mainly applicable to a lens module suitable for use in digital video cameras, digital cameras, cameras for mobile phones, etc., and more specifically, relates to an optical device suitable for use in automatic focus and zoom functions, and has a function of moving in a predetermined direction. Lens module for optical lenses. Background technique [0002] Conventionally, in order to provide a camera with autofocus and zoom functions, a mechanism for moving an optical lens along an optical axis is required, and a method using an electromagnetic motor is generally known. [0003] However, in recent years, optical devices represented by digital cameras and camera-equipped mobile phones have been miniaturized rapidly. Along with this, electric / mechanical conversion elements such as piezoelectric elements have been proposed from electromagnetic motors. The technology of the moving method of the optical lens is constantly becoming ma...

AI Technical Summary

Problems solved by technology

[0010] Specifically, in the case of the method disclosed in Patent Document 1, a structure for supporting the driving member in a movable manner with respect to the stationary member is necessary, and it is necessary to use an elastic member such as a leaf spring to frictionally couple the driving member and the driven member. Therefore, not only the structure of the lens module becomes complicated, but also the control of the friction force is difficult, so there is a problem that the moving speed of the driven object deviates

[0011] In addition, in the case of the method disclosed in Patent Document 2, the magnetization direction of the excitation member is uncertain. In the magnetic circuit formed by the driving member of the material, since the magnetic flux distribution is asymmetrical up and down, there is a problem that there is a significant difference in the moving speed when the lens is extended and when the lens is retracted.

Therefore, if the above-mentioned known technology is used to realize the autofocus and zoom functions at the same time, there will be a problem that the camera will become more complicated and larger.

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