Dual-Energy X-Ray Detector Pixel Misalignment Correction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In dual-energy nondestructive inspection devices, pixel correspondence between detectors can shift due to radiation source displacement or deformation, leading to pseudo-edges and reduced accuracy, making continuous calibration challenging.

Innovation Solution

A nondestructive inspection device with a conveyor unit, radiation source, and detectors in two energy ranges, where the detection unit calculates transmittance ratios to detect positional deviations and correct luminance data, ensuring pixel correspondence between detectors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If detectors are stacked in two stages to acquire radiation images in different energy ranges, then the inspection capability is improved, but pixel correspondence between detectors deteriorates due to radiation source displacement

Engineering Contradiction:
Improveinspection capabilityVSAvoidpixel correspondence
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent performs preliminary calibration to establish correspondence between pixels of upstream and downstream detectors before actual inspection. This preliminary mapping relationship is stored and used during continuous inspection to maintain pixel correspondence even when the radiation source position shifts, thus preventing degradation of measurement precision while maintaining dual-energy inspection capability

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements a feedback mechanism where the system continuously monitors the radiation source position and dynamically adjusts the pixel correspondence relationship between detectors. When displacement is detected, the system automatically updates the mapping parameters to compensate for the shift, ensuring that pixel correspondence is maintained throughout continuous operation without requiring frequent manual recalibration

Inventive Principle:
Principle #23Feedback

2Productivity

If continuous nondestructive inspections are performed, then productivity is improved, but calibration becomes difficult and pixel correspondence deteriorates

Engineering Contradiction:
Improveinspection efficiencyVSAvoidpixel correspondence
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The system performs preliminary calibration to establish an initial pixel correspondence mapping between detectors before continuous inspection begins. This pre-established mapping allows the system to maintain accurate pixel correspondence throughout continuous operation without requiring frequent interruption for recalibration, thus supporting high productivity while preserving reliability

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

During continuous inspection, the system continuously monitors radiation source position and dynamically updates pixel correspondence parameters through feedback control. This real-time adjustment mechanism ensures that pixel correspondence is automatically maintained throughout continuous operation, allowing high-speed consecutive inspections without degradation of measurement reliability

Inventive Principle:
Principle #23Feedback

3Duration of action of stationary object

If the radiation source position shifts due to thermal expansion, then measurement stability deteriorates, but continuous operation is maintained

Engineering Contradiction:
Improvecontinuous operationVSAvoidmeasurement stability
Core Design Contradiction:
Duration of action of stationary objectVSStability of the object's composition

Solution Approach 1:

The patent implements a feedback mechanism that continuously monitors radiation source position and detects shifts caused by thermal expansion. When displacement is detected, the system automatically updates the pixel correspondence mapping parameters to compensate for the shift, thereby maintaining measurement stability throughout continuous operation without requiring interruption for recalibration

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system dynamically changes the pixel correspondence parameters (mapping relationships between detectors) in response to radiation source position shifts. By adjusting these parameters in real-time based on detected displacement, the system compensates for thermal expansion effects and maintains measurement stability during continuous operation

Inventive Principle:
Principle #35Parameter changes

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

Enables early detection and correction of pixel misalignment, maintaining accurate radiation image processing and improving measurement precision by adjusting for positional shifts in the radiation source.

Implementation Method 1

a first radiation detector that detects the radiation emitted from the radiation source in a first energy range

Methodology Applied
Scientific EffectRadiation detection: Photoelectric Effect

Implementation Method 2

a second radiation detector that detects the radiation emitted from the radiation source in a second energy range higher than the first energy range

Methodology Applied
Scientific EffectRadiation detection: Photoelectric Effect

Implementation Method 3

a radiation source that irradiates the conveyor unit with radiation directed so as to intersect a conveying direction

Methodology Applied
Scientific EffectRadiation emission: X-Ray

Data Source

PatentEP2778663B1Nondestructive inspection device and method for correcting luminance data with nondestructive inspection device
Publication Date: 2019.02.27 HAMAMATSU PHOTONICS KK
  • EP2778663B1 patent drawingFigure 1
  • EP2778663B1 patent drawingFigure 2
  • EP2778663B1 patent drawingFigure 3(a)~3(b)

AI summary

A nondestructive inspection device 1 comprises an X-ray indicator 20, a low-energy detector 32, a high-energy detector 42, a low-energy transmittance calculation unit 72, a high-energy transmittance calculation unit 74, a detection unit 76, and a correction unit 78. The calculation unit 72 calculates a value indicating the transmittance of transmission X-rays in a low energy range. The calculation unit 74 calculates a value indicating the transmittance of transmission X-rays in a high energy range. The detection unit 76 detects a positional deviation detail of the X-ray indicator 20 according to a ratio between the transmittances calculated by both of the calculation units 72, 74. When the positional deviation detail of the X-ray indicator 20 is detected by the detection unit 76, according to the positional deviation detail, the correction unit 78 corrects X-ray luminance data detected by the detectors 32, 42.