Pixel Sensing Circuit Shot Noise Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional X-Ray imaging technologies, particularly analog signal imaging, suffer from low resolution and poor image quality, which is addressed by the development of X-Ray Digital Radiography (DR) using X-Ray Flat Panel Detectors. However, these detectors face challenges in reducing shot noises and improving signal-to-noise ratios.
Innovation Solution
A pixel sensing circuit comprising a signal generation sub-circuit, a reset sub-circuit, an amplification sub-circuit, and a read sub-circuit, where the reset and amplification sub-circuits are connected to different power supply lines, allowing for distinct power signals to be provided, reducing shot noises and enhancing the signal-to-noise ratio by controlling the timing of these signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If traditional analog signal imaging is used, then device complexity is reduced, but measurement precision and image quality deteriorate
Solution Approach 1:
The pixel sensing circuit is divided into four independent sub-circuits: signal generation sub-circuit, reset sub-circuit, amplification sub-circuit, and read sub-circuit. Each sub-circuit performs a specific function and can be independently optimized, allowing complex signal processing to be achieved through modular components rather than a monolithic complex circuit.
Solution Approach 2:
The patent introduces intermediate signal processing stages between light detection and final readout. The signal generation sub-circuit converts light signals to electrical signals, the amplification sub-circuit boosts the signal, and the read sub-circuit outputs the processed signal. These intermediary stages improve measurement precision without requiring the entire system to be complex.
2Reliability
If separate power supply lines for reset and amplification sub-circuits are used, then signal-to-noise ratio is improved, but device complexity increases
Solution Approach 1:
The power supply system is segmented into at least two separate power supply lines: a first power supply line connected to the reset sub-circuit and a second power supply line connected to the amplification sub-circuit. This segmentation allows independent control of power signals, reducing electrical interference and improving signal-to-noise ratio.
Solution Approach 2:
The patent controls the timing and voltage parameters of power signals provided to different sub-circuits. By adjusting the duration, voltage level, and timing of power signals on separate power supply lines, the system optimizes signal-to-noise ratio without requiring fundamentally complex power supply architecture.
3Measurement precision
If signal amplification is increased, then image quality is improved, but shot noises increase
Solution Approach 1:
The reset sub-circuit performs preliminary action by resetting the pixel before signal integration and providing a stable baseline signal. This preliminary resetting reduces variability and shot noises in the subsequent amplification process, allowing signal amplification to be performed on a more stable signal with fewer noises.
Solution Approach 2:
The patent introduces an amplification sub-circuit as an intermediary stage between signal generation and readout. This dedicated amplification stage allows controlled signal boosting with optimized noise characteristics, separating the amplification function from other circuit operations to minimize shot noise generation.
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
The solution effectively reduces shot noises and improves the signal-to-noise ratio, leading to enhanced image quality in X-Ray imaging technologies.
Implementation Method 1
the signal generation sub-circuit is connected to a bias signal line and the first node, and is configured to detect a light signal and convert the detected light signal into an electrical signal
Data Source
AI summary
Provided is a pixel sensing circuit, including a signal generation sub-circuit, a reset sub-circuit, an amplification sub-circuit, and a read sub-circuit. The reset sub-circuit is configured to provide a signal of a first power supply line to a first node under control of a reset signal line. The signal generation sub-circuit is configured to detect a light signal and convert the detected light signal into an electrical signal. The amplification sub-circuit is configured to provide an amplified electrical signal to a second node according to a signal provided by a second power supply line and under control of the first node. The read sub-circuit is configured to output the amplified electrical signal to a signal read line under control of a scan signal line.