Camera Actuator Position Sensor Arrangement for Shake Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing camera modules with shake correction functions, such as sensor shift, lack accurate detection and correction mechanisms for the moving destination of the image sensor, leading to difficulties in controlling the operation with high precision.
Innovation Solution
An actuator system comprising a fixed portion and a movable portion with a rectangular image sensor, coils, and position sensors, where coils are arranged on opposing sides of the image sensor, and position sensors are positioned to detect the displacement and rotation of the image sensor, enabling accurate control in three-axis directions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If vibration absorbing material such as soft gel or a soft spring is added between a component of a movable portion and a component of a fixed portion, then the shock resistance is improved, but the control accuracy of the movable portion deteriorates due to lack of detection and correction mechanisms
Solution Approach 1:
The patent introduces position detection means to detect the position of the movable portion and feedback control means to generate a feedback signal based on the detected position. This feedback signal is used to correct drive errors, forming a closed-loop control system that maintains high control accuracy even when vibration absorbing materials are present in the mechanical structure.
Solution Approach 2:
The patent introduces position detection means as an intermediary element that bridges the gap between the movable portion's actual position and the control system. This intermediary provides accurate position information despite the presence of vibration absorbing materials, enabling precise control without compromising shock resistance.
2Device complexity
If no position detection means is provided, then the device complexity is reduced, but the control accuracy of the movable portion deteriorates
Solution Approach 1:
The patent introduces position detection means to detect the position of the movable portion and feedback control means to generate a feedback signal based on the detected position. This feedback signal is used to correct drive errors, forming a closed-loop control system that maintains high control accuracy even when vibration absorbing materials are present in the mechanical structure.
Solution Approach 2:
The patent replaces open-loop mechanical control with closed-loop control that incorporates position detection and feedback. This substitution introduces electronic control elements that compensate for mechanical imperfections and uncertainties, achieving high precision without requiring overly complex mechanical structures.
3Measurement precision
If multiple position sensors are arranged corresponding to coil sets for detecting position and rotation, then the control accuracy in three-axis directions is improved, but the device complexity increases
Solution Approach 1:
The patent arranges position sensors corresponding to coil sets that can detect both position and rotation of the movable portion. This multi-functional sensor arrangement allows a single sensor system to perform multiple detection functions, reducing the need for separate sensors and minimizing overall system complexity while achieving high control accuracy in three-axis directions.
Solution Approach 2:
The patent combines position detection and rotation detection functions into a unified sensor system where position sensors are arranged to simultaneously provide information about both the position and orientation of the movable portion. This merging of detection functions reduces the total number of sensors needed and simplifies the control system architecture.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The actuator system allows for precise control of the image sensor's movement in three-axis directions, enhancing the accuracy of camera shake correction and autofocus operations.
Implementation Method 1
a magnet 420 and a coil 510; one position sensor 52 is provided for each set of coils 510, and the position sensor 52 is arranged at a position corresponding to one coil 510 in each set of coils 510
Implementation Method 2
a magnet 420 and a coil 510; drives the movable body in the x-axis direction and the y-axis direction
Data Source
AI summary
An actuator is disclosed having a fixed portion and a movable portion for mounting a rectangular image sensor. The movable portion includes a rectangular image sensor, coils and position sensors. The coils are arranged at positions corresponding to respective sides of the image sensor, and one pair of opposing two sides are respectively provided with two coils juxtaposed along each side. When the two coils arranged at positions right opposite each other corresponding to the opposing two sides are set as one set of coils, one position sensor is provided corresponding to each set of coils, and the position sensor is arranged at a position corresponding to one coil in each set of coils.