Local Dosimeter with Filtered Detector Pairs for Wide Energy Dose Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing area dosimeters lack accuracy in measuring ambient equivalent dose H*(10) over a wide energy range, particularly below 30 keV to 100 keV, and are not angle-independent, which is crucial for radiation protection in various applications.
Innovation Solution
A passive area dosimeter with a scattering body and two pairs of thermoluminescence detector elements, where one detector element in each pair is filtered by copper foils to adjust the spectral response, allowing for a weighted sum of measurements to achieve accurate and angle-independent dose measurement from 10 keV to 10 MeV.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single detector element is used without filters, then the device complexity is reduced, but the measurement precision deteriorates due to energy-dependent response in the range below 30 keV
Solution Approach 1:
The detector card is segmented into multiple detector elements (at least two) with different filter configurations. Each detector element measures the radiation dose with a different spectral response, allowing the system to resolve energy-dependent measurement errors by combining multiple measurements.
Solution Approach 2:
Filter foils are introduced as intermediary elements between the radiation field and the detector elements. These filters modify the spectral composition of incident radiation, creating differentiated measurement conditions that enable accurate dose reconstruction across a broad energy range.
2Measurement precision
If filter foils are added to adjust spectral response, then the measurement precision improves, but the device complexity increases
Solution Approach 1:
Different filter foils with specific materials and thicknesses are applied to different detector elements based on their required spectral response characteristics. This local differentiation of filter properties enables each detector element to be optimized for specific measurement conditions while maintaining a relatively simple overall device structure.
3Manufacturing precision
If the dosimeter is designed for specific measurement directions, then the manufacturing precision is improved, but the adaptability deteriorates due to lack of angle independence
Solution Approach 1:
The detector card is designed with multiple detector elements arranged to provide angle-independent measurement capability. The system can accurately measure ambient equivalent dose H*(10) regardless of the incident radiation direction, making it universally applicable in various radiation protection scenarios without requiring precise alignment.
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 dosimeter provides improved accuracy and direction independence in measuring ambient equivalent dose H*(10) across a broad energy range, reducing errors and enhancing measurement reliability in environments with varying radiation angles.
Implementation Method 1
Passive area dosimeters typically contain a passive detector element that receives and stores the incident radiation due to physical processes without the need for electrical power. A typical example of this are thermoluminescence detectors (TLD).
Implementation Method 2
one detector element in each pair is filtered by copper foils to adjust the spectral response
Implementation Method 3
A passive area dosimeter with a scattering body and two pairs of thermoluminescence detector elements
Data Source
Figure 1~2
Figure 3~5
Figure 6~7
AI summary
The invention relates to a local dosimeter for measuring the ambient equivalent dose (H* (10)) of photon radiation having a scattering body, a detector card having at least one pair of detector elements, preferably LiF chips, with the first of the two detector elements being positioned between two filter foils in order to spectrally filter the photon radiation, the second of the two detector elements not being arranged between filter foils like the first detector element, which means that the photon radiation hitting the second detector element has a different spectral distribution from the spectrally filtered photon radiation hitting the first detector element. The two measured values are summed in weighted form in order to obtain an optimized response characteristic, particularly in the range below 30 keV and possibly in the range above 1.3 MeV.