Image Pickup Apparatus Depth of Field Control for Multi-Distance Subjects
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Image pickup apparatuses face challenges in capturing images with multiple focus positions, leading to blurring and degradation in image quality due to variations in the positional relationship between the camera and subjects, especially when dealing with subjects at different distances.
Innovation Solution
An image pickup apparatus with an image sensor and a control circuit that adjusts the depth of field by capturing images at various focus positions and determining the optimal aperture settings based on subject distance distribution to prevent blurring, using a combination of pupil-divided images and focus stacking techniques.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a plurality of images having different focus positions is captured using focus stacking technique, then the entire imaging area can be in focus, but blurring of the subject and degradation in image quality occurs due to variations in positional relationship between camera and subject
Solution Approach 1:
The control circuit determines the depth of field required for capturing all subjects in focus before actually capturing the images. This preliminary determination of depth of field based on subject distances allows the system to prepare appropriate aperture settings and focus positions in advance, preventing blurring caused by insufficient depth of field coverage.
Solution Approach 2:
The system dynamically adjusts the depth of field by changing aperture size based on the determined requirements. The control circuit modifies capture conditions (aperture, focus positions) according to the actual subject distribution and distances, making the focus stacking process adaptive rather than static, thereby maintaining image quality across varying subject configurations.
2Manufacturing precision
If the depth of field is increased to capture all subjects in focus, then blurring is reduced, but the number of images that need to be captured and processed increases
Solution Approach 1:
The control circuit determines the minimum necessary depth of field required to capture all subjects in focus, rather than using a uniformly large depth of field for all cases. By calculating the specific depth of field needed based on subject distances and distribution, the system captures only the necessary number of images with appropriate focus positions, avoiding excessive image capture and processing while still ensuring all subjects are in focus.
3Adaptability or versatility
If multiple focus positions are captured to cover different subject distances, then all subjects can be in focus, but variations in positional relationship cause blurring in the combined image
Solution Approach 1:
The control circuit uses detected subject distances and distributions as feedback to determine the appropriate depth of field and focus positions for image capture. This feedback mechanism allows the system to adjust capture parameters based on actual subject configurations, ensuring that the combined image maintains high quality without blurring by optimizing focus stacking parameters for each specific scene.
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 effectively reduces blurring and enhances image quality by dynamically adjusting the aperture and depth of field, ensuring that all subjects within the image are in focus, even when they are at different distances from the camera.
Implementation Method 1
an image sensor configured to capture a plurality of images at different focus positions of an optical system
Implementation Method 2
different focus positions of an optical system
Implementation Method 3
a control circuit configured to control a depth of field of the optical system when the image sensor captures an image
Data Source
AI summary
An image pickup apparatus includes an image pickup unit configured to capture a plurality of images having different focus positions, and a depth of field control unit configured to control a depth of field when the image pickup unit captures an image, wherein, if it is determined that a plurality of subject areas satisfies a predetermined condition based on a distance for each subject area, a depth of field when the image pickup unit captures one of the plurality of images is increased, in comparison with a case where the predetermined condition is not satisfied. The predetermined condition includes a difference of any two in the plurality of subject areas being at a distance greater than a predetermine distance.