Portable OSL Reader Using LED and Photon Counting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing OSL readers require complex setups, high power lasers, and personal computers, making them bulky, power-intensive, and impractical for field measurements, and lack sensitivity and accuracy in determining radiation doses.
Innovation Solution
A portable, battery-powered OSL reader with a microprocessor that controls an LED light source, photodetector, and pulse counter, enabling fast and accurate determination of radiation doses using Pulsed Optically Stimulated Luminescence (POSL) without the need for a PC, featuring a compact design and low power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional OSL readers use high power YAG lasers and complex optical systems, then measurement precision is improved, but device complexity increases and portability is reduced
Solution Approach 1:
The patent changes the fundamental parameters of the light source from high-power YAG laser to LED, and operates the photodetector in photon counting mode rather than analog mode. This parameter change allows achieving comparable measurement precision with significantly reduced device complexity and power consumption
Solution Approach 2:
The patent replaces the complex mechanical/optical laser system with a simpler LED-based system. The LED provides sufficient stimulation light without requiring the complex beam control, intensity modulation, and alignment systems that YAG lasers demand, thereby reducing device complexity while maintaining measurement accuracy
2Measurement precision
If traditional OSL readers use high power lasers and sophisticated electronics, then measurement precision is improved, but power consumption increases
Solution Approach 1:
The patent changes the operational parameters by using LED instead of high-power laser and operating the photodetector in photon counting mode. This parameter change dramatically reduces power consumption while maintaining the ability to accurately determine radiation doses through digital photon counting
Solution Approach 2:
The patent employs pulsed LED illumination instead of continuous laser operation. The periodic pulsed action provides sufficient stimulation for OSL measurement while allowing the system to remain in low-power state between pulses, significantly reducing overall power consumption for portable field measurements
3Loss of information
If traditional OSL readers require personal computers and data acquisition boards, then data processing capability is improved, but ease of operation in field conditions is reduced
Solution Approach 1:
The patent merges the data processing functions directly into the portable OSL reader device itself. The microprocessor within the reader performs all necessary data processing, photon counting, and radiation dose calculation, eliminating the need for separate personal computers and data acquisition boards, thereby enabling true portability for field measurements
Solution Approach 2:
The portable OSL reader is designed to be self-contained and self-sufficient. It performs all measurements, processes all data, and provides all results without requiring external computer systems. This self-service capability makes the device easy to operate in remote field conditions where portable power and computational resources are limited
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 fast, accurate, and reliable field measurements of radiation doses with a high signal-to-noise ratio, low depletion per read, and the ability to record multiple measurements for later database upload, improving upon previous readers by being self-contained and sensitive.
Implementation Method 1
an LED light source for emitting a green illumination light for illuminating an optically stimulated luminescence (OSL) sensor
Implementation Method 2
a photodetector for detecting of blue luminescent light emitted by the OSL sensor
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention resides in an apparatus comprising an LED light source (134) for emitting a green illumination light (132) for illuminating an optically stimulated luminescence (OSL) sensor, a photodetector (162) for detecting of green luminescent light emitted by the OSL sensor, a pulse counter for counting photon pulses generated by a photodetector based on photons of luminescent light emitted by the OSL sensor and counted by the photodetector, and a microprocessor (166) for controlling the LED light source and the photodetector and the pulse counter. The microprocessor controls when the LED light source, the photodetector and the pulse counter are switched between an on state and an off state. The pulse counter is part of the microprocessor, and the microprocessor determines a radiation dose of one type of ionizing radiation to which the OSL sensor has been exposed based on the photon pulses counted by the pulse counter.