Imaging Device AD Conversion Timing for High Frame Rate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing imaging devices with multiple photodiodes under a single microlens lack efficient methods for high-speed AD conversion of signals from pixels arranged in multiple rows, particularly in configurations where first and second signals from each pixel overlap in their photoelectric conversion periods.
Innovation Solution
The imaging device incorporates multiple pixels with photoelectric conversion units, an AD conversion unit, and a control unit that coordinates the AD conversion of first and second signals from pixels arranged in rows, ensuring partial overlap in their conversion periods to optimize signal processing and enhance frame rate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple pixels with multiple photodiodes perform AD conversion of first and second signals sequentially, then signal processing accuracy is maintained, but processing speed and frame rate are limited
Solution Approach 1:
The patent implements preliminary action by having the first photoelectric conversion units complete their photoelectric conversion and output first signals before the second photoelectric conversion units begin their conversion. This staged approach allows the AD conversion unit to process first signals from multiple rows sequentially before transitioning to second signals, optimizing the timing and reducing waiting time while maintaining signal processing accuracy
Solution Approach 2:
The patent applies periodic action through the structured timing sequence where photoelectric conversion units alternately perform conversion for first signals and second signals in defined periods. The control unit manages this periodic operation, causing AD conversion to occur in organized stages: first signals from row 1, then row 2, then second signals from row 1, then row 2, creating an efficient periodic processing rhythm that enhances frame rate
2Productivity
If photoelectric conversion periods of first and second signals overlap, then processing efficiency is improved, but signal interference and conversion complexity increase
Solution Approach 1:
The patent segments the photoelectric conversion process into distinct first photoelectric conversion units and second photoelectric conversion units within each pixel. This segmentation allows the first units to operate in one time period while second units operate in another period, enabling partial overlap of conversion periods without direct interference. The control unit manages this segmented operation, reducing overall conversion complexity while improving processing efficiency
Solution Approach 2:
The patent implements dynamics by allowing the photoelectric conversion periods of first and second signals to partially overlap in time, rather than requiring completely sequential operation. The control unit dynamically coordinates the timing, causing first signals from some rows to be converted while second signals from other rows are simultaneously being converted, optimizing resource utilization and processing efficiency
3Productivity
If AD conversion processes signals from multiple rows in parallel, then frame rate increases, but signal processing accuracy and correction difficulty increase
Solution Approach 1:
The patent applies preliminary action by completing all first signal conversions from multiple rows before initiating second signal conversions. This staged approach ensures that each signal type is fully processed with appropriate correction parameters before transitioning to the next signal type, maintaining measurement precision while still achieving parallel processing benefits across multiple rows
Solution Approach 2:
The control unit implements feedback mechanisms to manage the AD conversion process, monitoring the completion of first signal conversions before initiating second signal conversions. This feedback control ensures that signal processing accuracy is maintained by coordinating the timing and sequence of conversions, preventing interference while optimizing the parallel processing capability across multiple pixel rows
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 configuration allows for efficient AD conversion of signals from overlapping photoelectric conversion periods, reducing waiting times and enhancing the frame rate of the imaging device by parallelizing operations and simplifying correction processes in AD conversion.
Implementation Method 1
multiple photodiodes are provided for a single microlens... electric charges generated by the photodiodes
Data Source
AI summary
Provided is an imaging device configured to sequentially perform AD conversion for A signals of pixels of the first row, A signals of pixels of the second row, A+B signals of the pixels of the first row, and A+B signals of the pixels of the second row.