Imaging Device Autofocus Speed via Frame Synthesis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current imaging devices face challenges in increasing the speed of the auto focus (AF) function, particularly in synchronizing the high imaging frame rate with the lower display frame rate, leading to reduced focusing speed and information loss in displayed images.
Innovation Solution
The imaging device incorporates an image data interface unit, an image synthesizing unit, and evaluation value generating units that synthesize and process image data across frames, allowing for the generation of evaluation values at the higher imaging frame rate while displaying images at the lower display frame rate without thinning out captured frames, thus maintaining image quality and increasing AF speed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the imaging frame rate is increased to improve AF speed, then the focusing speed is improved, but the display frame rate cannot keep up leading to synchronization issues and information loss in displayed images
Solution Approach 1:
The patent divides image data processing into separate pathways: one for AF evaluation value generation (using all captured frames at high frame rate) and another for display (selectively processing frames at display frame rate). This segmentation allows the AF function to utilize all captured image information while the display shows only necessary frames, resolving the contradiction between high imaging frame rate and display synchronization.
Solution Approach 2:
The patent introduces an image data selecting unit as an intermediary between the image sensor and the display device. This selector receives multiple frames from the high-speed image sensor and selectively passes frames to the display at the appropriate display frame rate, preventing information loss while maintaining synchronization between imaging and display operations.
2Measurement precision
If image data from all captured frames is used for AF evaluation, then the AF accuracy is improved, but the processing load increases when synchronizing with display frame rate
Solution Approach 1:
The patent segments the image data processing into distinct functional units: AF evaluation value generating units that process all captured frames for high-precision focus detection, and a separate image data selecting unit that manages display frame rate synchronization. This segmentation allows complex processing to be distributed and managed efficiently, reducing overall system complexity while maintaining high AF accuracy.
3Stability of the object's composition
If the display frame rate is reduced to match lower processing capabilities, then the synchronization is simplified, but the imaging frame rate must be reduced leading to slower AF response
Solution Approach 1:
The patent implements dynamic frame selection where the image data selecting unit adaptively chooses which captured frames to display based on the display frame rate requirements. This dynamic approach allows the system to maintain high imaging frame rate for fast AF response while flexibly synchronizing display output, achieving both speed and stability without rigid frame rate matching.
Data Source
AI summary
An imaging device includes an image data interface unit that outputs the first image data according to a pixel signal from a solid-state imaging device, an image data reading unit that reads image data from a storage unit and outputs the read image data as second image data, an image synthesizing unit that outputs third image data in which the first image data is synthesized with the second image data, an evaluation value generating unit that generates an evaluation value based on image data, a first image data selecting unit that inputs selected image data to the evaluation value generating unit, an image data writing unit that stores input image data in the storage unit via the data bus, a second image data selecting unit that inputs selected image data to the image data writing unit, and a display unit that displays an image corresponding to the third image data.