X-ray Detection Panel Residual Current Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Indirect type X-ray detectors face challenges with low sensitivity and high noise due to residual current components in thin-film transistors and photodiodes, leading to poor signal-to-noise ratio, image lag, and ghosting, making it difficult to achieve high-quality images, especially in low-dose applications and video imaging.
Innovation Solution
The X-ray detection panel incorporates two or three thin-film transistors, where one transistor processes electrical signals from the photodiode and another removes residual current components, and an optional third transistor amplifies the signal, improving sensitivity and signal-to-noise ratio. The panel includes a substrate with a photodiode, thin-film transistors, gate lines, data lines, and a bias line, with a microlens and transparent electrode for enhanced performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single thin-film transistor and photodiode are used per pixel, then device complexity is reduced, but signal-to-noise ratio deteriorates due to residual current accumulation
Solution Approach 1:
The pixel is divided into multiple functional units with separate thin-film transistors: one for signal processing and another dedicated to removing residual current components. This segmentation allows independent optimization of each function, enabling residual current removal without compromising signal processing, thereby improving signal-to-noise ratio while maintaining manageable device complexity
Solution Approach 2:
A second thin-film transistor acts as an intermediary component specifically dedicated to removing residual current from the photodiode and first thin-film transistor. This intermediary element addresses the harmful residual current without interfering with the primary signal processing function, effectively improving signal-to-noise ratio while adding only one additional component per pixel
2Ease of operation
If residual current components are not removed, then device operation is simpler, but image quality deteriorates due to noise and ghosting
Solution Approach 1:
The pixel circuit includes a self-service mechanism where the second thin-film transistor automatically removes residual current components that accumulate during operation. This self-cleaning function maintains high image quality without requiring external intervention or complex post-processing, balancing operational simplicity with image quality requirements
Solution Approach 2:
The harmful residual current components are extracted and removed from the pixel circuit through the dedicated second thin-film transistor. By separating the residual current removal function from the main signal processing path, the system maintains simple operation while achieving high image quality through selective extraction of unwanted current components
3Measurement precision
If photodiode sensitivity is increased to improve low-dose detection, then residual current effects become more prominent, worsening signal-to-noise ratio
Solution Approach 1:
The second thin-film transistor converts the harmful residual current into a removable component by providing a dedicated removal path. This allows the photodiode to operate at high sensitivity for low-dose detection while the residual current is simultaneously eliminated, transforming what was previously a limiting factor into a manageable parameter that no longer degrades signal-to-noise ratio
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 significantly improves the signal-to-noise ratio and image quality by effectively removing residual currents and amplifying signals, resulting in high-quality images with reduced noise and lag.
Implementation Method 1
a photodiode disposed on the substrate and generating an electrical signal in response to light illuminating the photodiode
Data Source
AI summary
An X-ray detection panel for X-ray detectors and a method of manufacturing the same are disclosed. The X-ray detection panel includes a substrate, a photodiode disposed on the substrate and generating an electrical signal in response to light illuminating the photodiode, a first thin-film transistor disposed on the substrate and processing the electrical signal generated by the photodiode, and a second thin-film transistor disposed on the substrate and removing a residual current component accumulated in the photodiode and the first thin-film transistor. The X-ray detection panel can improve actual sensitivity and signal-to-noise ratio (SNR).