Tri-Axis Close Loop Feedback Controlling Module for Electromagnetic Lens Driving Device

Abstract

The tri-axis close-loop feedback controlling module for electromagnetic lens driving device comprises a 6-pin Hall element. Two pins of the Hall element are coupled to an auto-focus module for providing a current to drive the auto-focus module to conduct auto-focusing operations along the Z-axis; while other four pins of the Hall element are coupled to a control unit. The control unit detects the X-Y axial positions of the auto-focus module relative to an OIS module and generates a control signal which is then sent to the Hall element. Therefore, the Hall element not only can provide its own feedback controlling function according to the Z-axial position of lens, but also can drive the auto-focus module based on the control signal corresponding to the X-Y axial positions of the auto-focus module, so as to achieve the goal of tri-axis close-loop feedback controlling for the electromagnetic lens driving device.

Description

[0001]This is a non-provisional application of PPA Ser. No. 61 / 819,737 filed on 2013 May 6, whose disclosures are incorporated by this reference as though fully set forth herein.BACKGROUND OF INVENTION[0002]1. Field of the Invention[0003]The invention refers to a tri-axis close-loop feedback controlling module for electromagnetic lens driving device, which employs a 6-pin Hall element to allow the electromagnetic lens driving device to control the focusing operations of the auto-focus module along the Z-axis based on a control signal generated according to the X-and-Y axial positions of the auto-focus module, so as to achieve the functions of tri-axis close-loop feedback control.[0004]2. Description of the Prior Art[0005]Digital photography technology has been widely applied to most of the portable electronic devices such as the cellular phones. Various miniaturized techniques in the lens module are involved to make all these applications possible; in particular, the voice coil moto...

AI Technical Summary

Benefits of technology

The present invention provides a tri-axis close-loop feedback controlling module for an electromagnetic lens driving device that uses a 6-pin Hall element. The Hall element detects signals generated by an OIS module to determine the position of the auto-focus module relative to the OIS module, which allows for precise alignment of the lens. The Hall element can also accept control signals from a control unit and provide the necessary current to drive the auto-focus module based on the control signal, achieving the goal of tri-axis close-loop feedback controlling for the electromagnetic lens driving device. The invention also includes a novel electric coupling structure to connect the six pins of the Hall element with the circuitries of both the auto-focus module and the OIS module, ensuring optimal performance of the feedback controlling module.

Problems solved by technology

However, in an optical system composed of an optic lens module, such as a camera system or a video recorder system, hand shake or some external situations usually occur to alter optical path so as to degrade the imaging upon the image-compensation module and further to obscure the formation of the images.

However, conventional technologies usually employ two different and yet independent control circuitries for the feedback circuits of the auto-focus module and the OIS module in the same camera device.

Unfortunately, because conventional technologies use two different and independent control and feedback circuits for the auto-focus module and OIS module to detect and control the movements of lens in the Z-axis and X-Y axes respectively, thus the responding and interacting speeds of the auto-focus module is relatively slower and delayed, which will cause delayed focusing operations when shakings occur.

In addition, because the entire lens module (including lens and auto-focus module) is movable horizontally relative to the OIS module, the circuitry design is very difficult for conventional technologies if someone try to integrate the feedback circuit of the auto-focus module with the feedback circuit of the OIS module into one single circuitry.

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