Photoelectric Conversion Device Multi-Row Focus Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing photoelectric conversion devices using the image plane phase difference detection method struggle to acquire focus detection signals over multiple rows without decreasing the frame rate, as the region for reading out signals from one photoelectric converter is limited, preventing comprehensive focus detection across entire image planes.
Innovation Solution
A photoelectric conversion device with a pixel array and memory units that allow for sequential transfer of signals from multiple columns, enabling the output of focus detection signals across multiple rows without reducing the frame rate by alternating the columns for signal transfer and using a combination of photoelectric converters for phase difference detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the region for reading out signals from one photoelectric converter is made smaller, then the frame rate is improved, but the ability to acquire focus detection signals over multiple rows deteriorates
Solution Approach 1:
The pixel array is divided into multiple regions, with different rows designated for different functions. Specifically, odd rows are used for phase difference detection (focus detection) while even rows are used for imaging, allowing simultaneous acquisition of both types of signals without interference and maintaining high frame rates
Solution Approach 2:
The patent utilizes the row dimension to differentiate between focus detection and imaging functions. By assigning specific row patterns (odd/even rows) to different purposes, the system expands the functional capacity along the row dimension, enabling comprehensive focus detection across multiple rows while preserving frame rate performance
2Measurement precision
If focus detection signals are acquired over multiple rows, then the focus detection accuracy is improved, but the frame rate decreases
Solution Approach 1:
The pixel array is segmented into dedicated phase difference detection regions (odd rows) and imaging regions (even rows). This segmentation allows focus detection to be performed across multiple rows simultaneously without requiring sequential reading of all rows, thereby maintaining high frame rates while achieving comprehensive focus detection coverage
Solution Approach 2:
The system enables continuous simultaneous operation of both phase difference detection and imaging functions across different rows. By reading out signals from odd rows for focus detection and even rows for imaging in parallel, the system maintains continuous useful action for both functions without interruption or frame rate reduction
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
Enables focus detection over multiple rows without lowering the frame rate by optimizing signal transfer and using dual photoelectric converters for comprehensive phase difference measurement, improving focus detection accuracy and maintaining high frame rates.
Implementation Method 1
each pixel of an imaging element includes two photoelectric converters corresponding to two partial pupils
Data Source
AI summary
A photoelectric conversion device includes pixels including first and second photoelectric converters, a memory unit, and a transfer unit for transferring signals in the memory unit to a processing unit. The pixels output a first signal based on a signal of the first photoelectric converter, and a second signal based on signals of the first and second photoelectric converters. The transfer unit performs on row-by-row a first transfer period of transferring the first signal in the memory unit and a second transfer period of transferring the second signals held in the memory unit. A column a pixel outputting the first signal transferred during the first period of a first row is arranged is different from a column a pixel outputting the first signal transferred during the first period of a second row is arranged.