Optical Unit Shake Correction with Axial Magnet and Coil
Solution Overview
Problem
Existing optical units with shake correction functions face issues of increased inertia and reduced responsiveness due to the radial placement of the coil and magnet, leading to larger size and higher power consumption, as well as interference from magnetic forces affecting drive mechanisms.
Innovation Solution
The optical unit is designed with a gimbal mechanism and a shake correction drive mechanism where the oscillating magnet and coil are positioned closer to the optical axis, and a common magnet is used for both mechanisms to reduce size and improve responsiveness, with elastic members biasing the oscillation support points to prevent distortion and enhance stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the coil and magnet are arranged radially outside the movable frame, then the oscillation displacement of the optical module increases, but the inertia increases and responsiveness declines
Solution Approach 1:
The patent transitions from radial arrangement (outside the movable frame) to axial arrangement (inside the movable frame along the optical axis), changing the spatial dimension of the drive mechanism. This dimensional change allows the coil and magnet to be positioned closer to the optical axis while maintaining effective oscillation displacement, thereby reducing inertia and improving responsiveness without sacrificing correction capability
2Length of moving object
If the coil and magnet are arranged radially outside the movable frame, then the oscillation displacement increases, but the size of the optical unit increases
Solution Approach 1:
The patent nests the shake correction drive mechanism (coil and magnet) within the movable frame structure, specifically positioning them inside the movable frame along the optical axis. This nesting approach allows the drive mechanism to occupy space that would otherwise be unused, eliminating the need for additional radial space and preventing increase in the overall size of the optical unit while maintaining adequate oscillation displacement
3Length of moving object
If the coil and magnet are enlarged to increase oscillation displacement, then the oscillation displacement increases, but the weight of the holder increases and power consumption increases
Solution Approach 1:
The patent changes the spatial parameters of the drive mechanism from radial positioning to axial positioning along the optical axis. This parameter change allows the coil and magnet to be positioned closer to the optical axis at smaller dimensions, achieving the required oscillation displacement through optimized geometric arrangement rather than through size enlargement, thereby reducing weight and power consumption
4Length of moving object
If the coil and magnet are arranged radially outside the movable frame, then the oscillation displacement increases, but the power consumption increases
Solution Approach 1:
The patent optimizes the spatial parameters of the drive mechanism by repositioning the coil and magnet from radial to axial arrangement along the optical axis. This parameter optimization enables the system to achieve the necessary oscillation displacement with smaller, more efficient components positioned closer to the optical axis, reducing the energy required for shake correction operations
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
This configuration reduces the oscillation displacement and inertia of the optical module, improving responsiveness and power efficiency while allowing for a smaller form factor and stable operation of the shake correction and autofocus functions.
Implementation Method 1
a shake correction drive mechanism configured to cause the movable body to oscillate with respect to the fixed body around the two axial lines, such that the shake correction drive mechanism has an oscillating magnet, and an oscillating coil capable of generating an electromagnetic force within the magnetic field of the oscillating magnet
Data Source
AI summary
An optical unit may include a movable body having a lens and an imaging element; a fixed body configured to support the movable body; a gimbal mechanism configured to oscillatably support the movable body; and a shake correction drive mechanism configured to cause the movable body to oscillate with respect to the fixed body around the two axial lines. The shake correction drive mechanism may include an oscillating magnet, and an oscillating coil to generate an electromagnetic force within a magnetic field of the oscillating magnet. The gimbal mechanism may include an annular movable frame surrounding a periphery of the movable body, and four oscillation support points supporting the movable frame with respect to the movable body and the fixed body on the two axial lines. The movable frame may be arranged outwardly in a radial direction perpendicular to the optical axis from the shake correction drive mechanism.