Imaging Apparatus High Luminance Focus Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional imaging apparatuses face difficulties in focusing on subjects with high luminance due to false focal point detection and low-frequency evaluation data issues, leading to incomplete focus or failure in achieving the correct focal point.
Innovation Solution
An imaging apparatus that includes a focus lens, a CCD, a luminance signal generator, low-frequency and high-frequency filters, and a processor that determines the influence of high luminance based on RGB signal levels, switching between low-frequency and high-frequency evaluation data for accurate focal point detection, ensuring the focus lens can accurately focus on subjects with high luminance by using high-frequency components when necessary.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If low-frequency evaluation data is used for AF control, then the lens can reach the focal point quickly, but the data shows false peaks when capturing subjects with high luminance causing inaccurate focus
Solution Approach 1:
The system dynamically switches between low-frequency and high-frequency evaluation data based on the imaging conditions. When high luminance subjects are detected, the system transitions from using low-frequency evaluation data (which causes false peaks) to high-frequency evaluation data (which provides accurate focus detection), making the evaluation method adaptive to changing conditions rather than static
Solution Approach 2:
The invention changes the parameter of frequency selection in the evaluation data processing. By switching between low-frequency and high-frequency components based on luminance detection, the system optimizes the evaluation data characteristics to match the imaging conditions, resolving the contradiction between speed and accuracy
2Measurement precision
If high-frequency evaluation data is used for AF control, then the focal point can be detected accurately, but the lens takes longer to reach the focal point
Solution Approach 1:
The system uses dynamic conditional switching to optimize performance. In normal conditions without high luminance subjects, low-frequency data is used for fast focusing. When high luminance subjects are detected, the system dynamically switches to high-frequency data for accurate focus detection, thus optimizing both speed and accuracy based on real-time conditions
Solution Approach 2:
The system performs preliminary detection of high luminance subjects before initiating AF control. By detecting the presence of high luminance subjects in advance and pre-selecting the appropriate evaluation data frequency band, the system avoids the false peak problem from the outset, enabling accurate and efficient focus acquisition
3Device complexity
If the system uses a fixed AF evaluation method, then the control logic is simple, but the system cannot adapt to different imaging conditions such as high luminance subjects
Solution Approach 1:
The system achieves multi-functionality by having the AF control unit perform multiple functions: detecting high luminance subjects, selecting appropriate evaluation data frequency bands, and executing AF control. This universal approach allows a single system to handle both normal imaging conditions and high luminance subject conditions effectively
Solution Approach 2:
The control logic transitions from static to dynamic by incorporating conditional branching based on luminance detection. The system maintains relative simplicity while adding adaptability through dynamic selection of evaluation methods, achieving a balance between complexity and versatility
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 the imaging apparatus to accurately detect and focus on subjects with high luminance, avoiding false focal points and ensuring quick and precise focus, regardless of the color of the subject, by using high-frequency evaluation data when necessary and low-frequency data when not influenced by high luminance.
Implementation Method 1
a CCD (1002) that converts an optical image input through the focus lens (1001) into electric signals in each color of RGB
Implementation Method 2
a low-frequency filter (1004) that passes low-frequency components of the luminance signal output from the luminance signal generating unit (1003), each of which has a frequency not higher than a predetermined frequency, and a high-frequency filter (1005) that passes high-frequency components
Data Source
AI summary
An imaging apparatus includes an imaging device operable to convert an optical image input through a focus lens for adjusting focus into electric signals in each of RGB colors, a luminance signal generator operable to generate a luminance signal based on the electric signal output from the imaging device, a low-frequency filter for transmitting low-frequency components of the luminance signal output, which has a frequency lower than a predetermined frequency, a high-frequency filter for transmitting high-frequency components of the luminance signal output, which has a frequency higher than a predetermined frequency, and a processor. The processor determines if focusing is influenced by a subject with high luminance. If determining that focusing is influenced, the unit detects a focal point based on high-frequency components. If determining that focusing is not influenced, the unit detects a focal point based on low-frequency components and then based on high-frequency components.