Imaging Device Saturation Detection for Accurate Focus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In imaging devices that add ranging signals from multiple pixels, saturation in one or more signals can lead to errors in ranging information, affecting the accuracy of imaging systems.
Innovation Solution
An imaging device with a pixel unit, an adder unit, a determination unit, and an output unit that processes signals from multiple photoelectric conversion units, where the adder unit combines signals from different pixels, and the determination unit checks for saturation, allowing the system to exclude signals above a threshold from the ranging information for accurate focus detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If ranging signals from multiple pixels are added to improve signal strength and focus detection capability, then focus detection accuracy is improved, but error in ranging information occurs when saturation is present in at least one signal
Solution Approach 1:
The determination unit performs preliminary detection of saturation in each ranging signal before the adder unit combines them. By checking whether signal charges exceed a predetermined threshold before addition, the system prevents saturated signals from contaminating the summed result, thus maintaining both focus detection accuracy and ranging information reliability
Solution Approach 2:
The determination unit acts as an intermediary between the pixel unit and the adder unit. It mediates the ranging signals by identifying and flagging saturated signals, allowing the adder unit to selectively process only valid non-saturated signals, thereby ensuring accurate ranging information while preserving focus detection capability
2Productivity
If all ranging signals from multiple pixels are used for focus detection to maximize data utilization, then processing efficiency is improved, but error propagation occurs when saturation is present in any signal
Solution Approach 1:
The determination unit extracts and identifies saturated signals from the group of ranging signals before they are combined. By separating saturated signals (which contain errors) from non-saturated signals, the system can exclude only the problematic signals while still utilizing valid signals for focus detection, thus maintaining processing efficiency without error propagation
Solution Approach 2:
The system applies local quality control by treating each ranging signal individually based on its saturation status. Instead of uniformly processing all signals, the determination unit applies different handling (inclusion or exclusion) to each signal based on its local condition, ensuring that only high-quality non-saturated signals contribute to the focus detection result
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
This approach reduces the likelihood of errors in ranging information due to saturation, ensuring more accurate focus detection and image processing by handling saturation flags effectively.
Implementation Method 1
m photoelectric conversion units that generate signal charges
Data Source
AI summary
Provided is an imaging device that includes a pixel unit in which each of a plurality of pixels includes m photoelectric conversion units and each of at least a part of the plurality of pixels outputs a first signal based on signal charges of n photoelectric conversion unit or units, where n is less than m; an adder unit configured to add a plurality of first signals output from a plurality of pixels different from each other; a determination unit configured to compare each of the plurality of first signals and a predetermined threshold to determine whether or not the plurality of first signals added by the adder unit include a signal larger than a predetermined threshold; and an output unit configured to output a determination result and the added signal.