Variable Optical Zoom Autofocus Compensation for Precise FOV Transitions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing variable optical zoom (VOZ) systems experience a reduced field-of-view due to autofocus adding additional zoom levels, leading to an unintended zoom level greater than the user-indicated level, resulting in unstable exposure and white balance during zoom transitions.
Innovation Solution
The system calibrates the zoom level by predicting the autofocus contribution and adjusting the lens module arrangement to compensate for it, ensuring the realized zoom level matches the user's intended level, maintaining a constant field-of-view and stable exposure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If autofocus is activated to automatically focus on objects, then focusing speed and ease of operation are improved, but the zoom level becomes inaccurate and field-of-view changes unexpectedly
Solution Approach 1:
The system applies preliminary anti-action by predicting the autofocus-induced zoom change before autofocus executes, then pre-adjusting the lens module position in the opposite direction to compensate. This ensures the final zoom level matches the user-indicated level despite autofocus activation.
Solution Approach 2:
The system uses feedback by continuously monitoring the relationship between autofocus activation and resulting zoom level changes. Historical data from autofocus events is used to build a predictive model that estimates future zoom changes, enabling proactive compensation rather than reactive correction.
2Measurement precision
If the lens module is adjusted to compensate for autofocus zoom, then zoom level accuracy is improved, but the system complexity increases due to additional control calculations
Solution Approach 1:
The system performs preliminary action by pre-calculating compensation values based on historical autofocus data before actual autofocus events occur. The predictive model is built in advance using accumulated data, allowing rapid compensation decisions during real-time operation without complex on-the-fly calculations.
Solution Approach 2:
The system applies parameter changes by transforming the control approach from direct lens position control to predictive compensation control. Instead of reacting to each autofocus event individually, the system changes the control parameter to a predicted compensation value derived from statistical analysis of historical data, simplifying the real-time control logic.
3Reliability
If the VOZ system maintains precise zoom levels during autofocus, then image quality and exposure stability are improved, but the response time may be reduced due to compensation calculations
Solution Approach 1:
The system uses preliminary action by pre-computing compensation values during idle periods or between frames, storing them for rapid retrieval during autofocus events. This separates the computationally intensive model-building phase from the time-critical compensation execution phase, maintaining both accuracy and speed.
Solution Approach 2:
The system applies partial action by implementing compensation only for the predicted portion of zoom change, rather than attempting to perfectly counteract all effects. This approximate compensation approach reduces computational overhead while maintaining sufficient image quality and exposure stability for practical purposes.
Data Source
AI summary
This disclosure provides systems, methods, and devices for image signal processing that support precise zoom level transitions. In a first aspect, a method of image processing includes receiving a zoom command to transition from a first zoom level to a second zoom level for a variable optical zoom (VOZ) system; determining a first arrangement of a lens module of the VOZ system based on the second zoom level and an autofocus arrangement of the lens module; determining a second arrangement of the lens module based on the first arrangement; and controlling the VOZ system to adjust the lens module to a third arrangement associated with the second zoom level based on the second arrangement and the autofocus arrangement of the lens module. Other aspects and features are also claimed and described.