Flat Panel Detector FPN Correction Using Non-Conductive Readout
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radiation imaging apparatuses using flat panel detectors face challenges in correcting fixed pattern noise (FPN) due to fluctuations in radiation application, leading to striped artifacts in the radiation image.
Innovation Solution
A radiation imaging apparatus that performs a first operation with switch elements in a non-conduction state and a second operation with a predetermined pixel in a conduction state during irradiation, using signal values from both operations to correct the second signal value, thereby reducing crosstalk noise and artifacts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If FPN correction is performed using conventional methods, then fixed pattern noise is reduced, but striped artifacts appear when radiation applied fluctuates during signal reading
Solution Approach 1:
The patent segments the signal reading process into two distinct operations: a first operation where switch elements are in non-conduction state to measure crosstalk noise, and a second operation where switch elements are in conduction state to read actual pixel signals. This segmentation allows separate measurement and correction of crosstalk noise, preventing it from contaminating the main image data and eliminating striped artifacts while maintaining FPN correction accuracy
Solution Approach 2:
The patent introduces an intermediary measurement step using a non-conduction state reading operation. This intermediary operation measures the crosstalk noise component separately before the main signal reading, allowing the noise to be identified and subtracted from the final image data. This intermediary approach prevents direct contamination of image signals while enabling accurate noise correction
2Productivity
If signals are read out while keeping irradiation with radiation, then image acquisition is continuous, but crosstalk noise fluctuates causing image quality degradation
Solution Approach 1:
The patent performs a preliminary action by executing the first operation (non-conduction state reading) before or during the second operation (conduction state reading). This preliminary measurement of crosstalk noise allows the system to compensate for noise fluctuations in real-time during continuous irradiation, maintaining both image acquisition continuity and signal accuracy
Solution Approach 2:
The patent implements a feedback mechanism where crosstalk noise measured during the first operation is used to correct signals from the second operation. This feedback loop continuously compensates for noise fluctuations caused by radiation variations, enabling continuous image acquisition while maintaining high signal accuracy through real-time noise correction
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 approach effectively suppresses striped artifacts in radiation images by averaging signal values, ensuring high-quality image acquisition even with fluctuating radiation doses.
Implementation Method 1
a conversion element configured to convert radiation into signal charge
Data Source
AI summary
A radiation imaging apparatus including pixels each including a conversion element and a switch element, a signal line to which signals are supplied from the pixels, a readout circuit reading out a signal supplied to the signal line and a processor processing a signal read out by the readout circuit, is provided. The readout circuit performs, during irradiation with radiation, a first operation of reading out a signal while the switch element of each of the pixels is in a non-conduction state and a second operation of reading out a signal while the switch element of a predetermined pixel of the pixels is in a conduction state. The processor corrects a second signal value of a signal read out by the second operation by using a first signal value of a signal read out by the first operation.