Optical Apparatus Focus Lens Control via Dual Driver Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical apparatuses face challenges in maintaining focus followability during zooming due to the mismatch between the moving speed of the focus lens and the magnification varying lens, leading to deteriorated focus control.
Innovation Solution
An optical apparatus with a first driver to move the focus lens and a second driver to control the first driver's movement, utilizing a controller to acquire and adjust the moving amount of the second driver to synchronize the focus lens's movement with the magnification varying lens, thereby improving focus followability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a focus motor is moved using a cam during zooming, then the focus lens can be driven mechanically, but the moving amount detected by the position detection system differs from the actual moving amount, causing mismatch between focus lens speed and magnification varying lens speed
Solution Approach 1:
The patent replaces the mechanical cam-driven focus motor system with an electromagnetic drive system (voice coil motor or piezoelectric actuator). This substitution eliminates the mechanical transmission chain that caused position detection mismatch, allowing direct and accurate control of the focus lens position according to the detected position of the magnification varying lens.
Solution Approach 2:
The patent introduces a position detection system that detects the position of the magnification varying lens as an intermediary to control the focus lens position. By using the detected position information as a reference, the system can accurately determine the required focus lens position to maintain focus during zooming, resolving the mismatch problem.
2Device complexity
If the focus lens moving speed does not match the magnification varying lens moving speed, then the mechanical structure is simpler, but the focus followability deteriorates
Solution Approach 1:
The patent implements a feedback control system where the position of the magnification varying lens is continuously detected, and based on this feedback, the focus lens position is adjusted in real-time. This closed-loop control ensures that the focus lens moves at the appropriate speed to maintain focus, significantly improving focus followability during zooming operations.
Solution Approach 2:
The patent employs dynamic control of the focus lens position based on the real-time position of the magnification varying lens. Rather than using a fixed mechanical linkage, the system dynamically adjusts the focus lens position according to the zooming speed and direction, enabling adaptive focus followability across different zooming conditions.
3Length of moving object
If the overall length of the optical apparatus is reduced, then the apparatus becomes more compact, but the focus correction mechanism may be compromised
Solution Approach 1:
The patent replaces traditional mechanical focus correction mechanisms with electromagnetic drive systems (voice coil motor or piezoelectric actuator) that can achieve the same focus correction function with a more compact structure. This substitution allows for reduced overall apparatus length while maintaining or improving focus correction capability through precise electromagnetic actuation.
Data Source
AI summary
An optical apparatus includes a first driver configured to move a focus lens in an optical axis direction, a second driver configured to move a first driver in the optical axis direction, and a controller configured to control driving of the first driver according to a moving amount of the first driver by the second driver.