Image Sensor ADC Selection for Fast Readout and Dynamic Range
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional image pickup devices face challenges in expanding dynamic range, reducing noise, and achieving high-speed data reading while handling various data output formats, as they are limited in functionality and power efficiency.
Innovation Solution
An image pickup device with a selection unit that dynamically selects the number of A/D converters for each pixel column and controls their settings, including output destinations, read rates, and gain settings, allowing for multiple paths and averaging of signals to enhance data output versatility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple A/D converters are provided for each pixel column to improve reading speed and resolution, then high-speed data reading and high resolution are achieved, but the device complexity and power consumption increase
Solution Approach 1:
The patent implements dynamic selection of A/D converter quantity and configuration through control circuits that can adaptively adjust the number of active ADCs and their operational modes based on imaging requirements. This allows the system to transition between high-speed reading mode (using multiple ADCs) and power-saving mode (using fewer ADCs), resolving the contradiction between reading speed and device complexity/power consumption.
2Measurement precision
If multiple A/D converters are used to improve resolution and dynamic range, then measurement precision is improved, but power consumption increases
Solution Approach 1:
The patent employs partial action by enabling only the necessary number of A/D converters based on current imaging requirements. When high precision is needed, multiple ADCs are activated; when standard precision suffices, fewer ADCs are used. This partial activation strategy maintains measurement precision when needed while significantly reducing power consumption during normal operation.
Solution Approach 2:
The system changes operational parameters by adjusting the number of active A/D converters and their conversion settings dynamically. This parameter adjustment allows the device to optimize the balance between precision and power consumption by selecting appropriate ADC configurations based on scene complexity, lighting conditions, and imaging priorities.
3Measurement precision
If A/D conversion is performed multiple times to reduce noise and expand dynamic range, then measurement precision is improved, but processing time increases
Solution Approach 1:
The patent performs preliminary A/D conversion operations during the exposure period or immediately thereafter, preparing converted signals in advance before final image processing is required. This preliminary conversion allows subsequent noise reduction and dynamic range expansion to be performed more efficiently, reducing the overall processing time while maintaining improved measurement precision.
4Adaptability or versatility
If the number of A/D converters is increased to handle various data output formats, then adaptability is improved, but device complexity increases
Solution Approach 1:
The patent implements multi-functionality by designing A/D converters that can operate in multiple modes and configurations within the same hardware architecture. The control circuits enable these universal converters to adapt to different data output formats (such as RAW, JPEG, different bit depths) without requiring separate dedicated converters for each format, thus improving adaptability while controlling device complexity.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present disclosure relates to an image pickup device, a control method, and an image pickup apparatus, which can implement more various data outputs. An image pickup apparatus of the present disclosure includes a pixel array in which incident light of an object is photoelectrically converted by a photoelectric conversion element at each of a plurality of pixels arranged in a matrix form, a selection unit that selects the number of A/D converters that output a pixel signal of each pixel in the pixel array, and a control unit that controls the selection unit and causes the selection unit to select the number of the A/D converters according to a request. The present disclosure can be applied to an image pickup device, a control method, and an image pickup apparatus.