MEMS Actuator Orientation Sensing via Capacitance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Camera modules lack an efficient method to determine their own orientation, relying on external sensors, which increases size and complexity, and existing auto-focus systems are not optimized for varying camera angles, affecting accuracy and efficiency.
Innovation Solution
A camera module with a MEMS actuator that uses capacitance sensing to determine orientation by positioning lenses based on gravitational effects, allowing for auto-focus routines tailored to specific orientations, eliminating the need for external orientation sensors and optimizing focus operations across different angles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If external orientation sensors are added to determine camera orientation, then orientation sensing capability is improved, but device size and complexity increase
Solution Approach 1:
The patent applies multi-functionality by enabling the MEMS actuator to serve dual purposes: its primary function of moving the lens for autofocus and a secondary function of sensing camera orientation through capacitance measurements. This eliminates the need for separate orientation sensors, thereby improving orientation sensing capability without increasing device complexity or size.
Solution Approach 2:
The system implements self-service by utilizing the existing MEMS actuator components (capacitance sensors) to perform orientation sensing without requiring additional dedicated sensors. The actuator essentially senses its own position and the camera's orientation simultaneously, reducing overall system complexity while maintaining sensing capabilities.
2Device complexity
If existing auto-focus systems are used without orientation optimization, then device complexity is maintained at lower levels, but focus accuracy and efficiency deteriorate at varying camera angles
Solution Approach 1:
The patent applies dynamics by making the autofocus system adaptive to different camera orientations. The processor dynamically adjusts autofocus parameters and lens movement commands based on real-time orientation data from the MEMS actuator, allowing the system to maintain high focus accuracy across varying angles without requiring a completely redesigned system.
Solution Approach 2:
The system implements feedback by continuously monitoring the capacitance values from the MEMS actuator to determine camera orientation and using this information to adjust autofocus operations. This closed-loop approach enables the system to compensate for gravitational effects on the lens at different orientations, improving focus accuracy while maintaining reasonable system complexity.
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 solution enables accurate and efficient auto-focus operations across various orientations, reducing module size and complexity by utilizing existing MEMS actuator data for orientation sensing and focus calibration, enhancing camera performance and user experience.
Implementation Method 1
utilizes a capacitance sensing capability of a MEMS (microelectrical mechanical system) auto-focus (AF) actuator
Implementation Method 2
positioning lenses based on gravitational effects
Data Source
AI summary
A camera module includes an actuator coupled to one or more movable lenses of an optical train and configured to move the one or more lenses relative to the image sensor to provide zoom or autofocus or both to the camera module. The actuator is configured to bias one or more pairs of actuator components, and to measure one or more capacitances of the one or more pairs of actuator components, and to determine an orientation of the camera module based on the one or more measured capacitances, and to provide information accordingly for the actuator to step through an auto-focus process that is specifically tailored to one of multiple sub-ranges of camera pointing angles.