Distance Measurement Correction for Curvature of Field Aberration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image processing devices face errors in calculating distance information due to varying focus positions across image heights in imaging optical systems, leading to inaccurate distance measurements.
Innovation Solution
A processing device that calculates distance information by extracting frequency components from multiple images with different blur degrees and corrects the information using image height-specific correction data, ensuring accurate distance measurement even with aberrations like curvature of field and chromatic aberration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If distance information is calculated using blur degree difference in images from an imaging optical system, then distance measurement can be obtained, but measurement precision deteriorates due to focus position variations across image heights
Solution Approach 1:
The patent applies local quality by deriving separate focus position information for different regions (image heights) and using region-specific correction values. The correction value derivation unit calculates correction values based on blur degree differences and focus position information specific to each image height region, ensuring that each region's distance measurement is corrected according to its unique optical characteristics rather than using a uniform correction approach.
Solution Approach 2:
The patent implements feedback through an iterative correction process where the correction value derivation unit continuously refines correction values based on the relationship between blur degree differences and focus position information. The correction information output unit then applies these feedback-derived correction values to the distance information, creating a closed-loop system that adapts to optical aberrations.
2Measurement precision
If correction data is applied for each image height, then measurement precision improves, but device complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the image into multiple height regions and processing each region separately. The correction value derivation unit processes different image height regions independently, deriving correction values specific to each segment. This allows the system to manage complexity through modular processing while achieving high precision through region-specific corrections.
Solution Approach 2:
The patent implements preliminary action by pre-calculating and storing correction values in a correction table before actual distance measurement. The correction value derivation unit generates correction values in advance based on blur degree differences and focus position information, which are then stored and applied during measurement. This pre-processing reduces real-time computational complexity while maintaining high precision.
Data Source
AI summary
A processing device which obtains distance information of a subject, including: a calculation unit configured to calculate the distance information of the subject from a difference in blur degree of a plurality of images photographed by an imaging optical system; a correcting unit configured to correct the distance information using correction data in accordance with an image height in the imaging optical system; and an extraction unit configured to extract at least one frequency component from each of the plurality of images, wherein the calculation unit calculates the distance information from a difference in blur degree in the plurality of images in the at least one frequency component; and the correcting unit corrects the distance information using correction data in accordance with an image height in the at least one frequency component.