Article source: https://doi.org/10.1016/j.radmeas.2025.107377

In the vast field of scientific research, precise measurement tools are often the key driving force behind the development of disciplines. Here, we would like to introduce a milestone device in the fields of solid dosimetry and archaeological chronology - the Lexsyg series luminescence analyzer. This series of equipment is carefully crafted by Freiberg Instruments, including two products, Lexsyg Research and Lexsyg Smart. Since its launch, it has been widely used in numerous laboratories around the world, providing strong technical support for fields such as geology, archaeology, radiation protection, and materials research. In 2025, the Freiberg luminescence tester in Germany will undergo a major upgrade, driving new changes in scientific research and applications through technological innovation

1、 Overview of Lexsyg series devices

The Lexsyg series equipment is designed specifically for measuring fluorescence and luminescence, and can perform radioluminescence, thermoluminescence, and photoluminescence measurements during and after excitation. Its design concept is advanced, with powerful functions that can meet the diverse needs of different users.

2、 Lexregresearch: a pioneer in scientific research with excellent functionality

1. Special design for efficient measurement

Lexregresearch was launched in 2012 and will undergo a major upgrade in 2025. It adopts an innovative design that separates the sample carrier storage from the measurement cavity, effectively avoiding optical and radiation crosstalk and ensuring the accuracy of measurement results. The equipment is equipped with an 80 bit sample storage wheel, which supports sample loading and unloading during the measurement process, achieving truly uninterrupted measurement. It has upgraded the single particle application's EMCCD and other functions, greatly improving experimental efficiency. At the same time, it has three mechanical motion planes and five sample processing positions, which can perform multiple operations simultaneously, such as excitation, bleaching, irradiation, and measurement, greatly enhancing the flexibility of the experiment.

2. Modular architecture, expanding infinite possibilities

The modular design of Lexregresearch is one of its major highlights. The equipment is equipped with automatic replacement detectors, which can install up to four different types of detectors, such as photomultiplier tubes (PMT), charge coupled devices (CCD), etc., and can quickly switch according to experimental needs to meet different measurement requirements. It can also install up to three ionizing radiation sources, including alpha, beta, and X-ray sources, and some radiation sources have highly uniform fields, providing more options for experiments. In addition, the device supports multiple excitation methods, such as irradiation, thermal excitation, and photoexcitation. The photoexcitation wavelength can reach three types, and with two sets of automatic six position filter wheels, the detection window can be accurately controlled to achieve precise measurement of different luminescent signals.

3. Powerful functions to assist scientific research exploration

This device has spectral measurement function, which can deeply analyze the luminescence characteristics and provide important data support for scientific research. Its Peltier cooling module can cool the sample to -50 ° C, meeting the requirements of low-temperature measurement. In infrared photoluminescence (IRPL) measurement, the signal intensity increases significantly at -40 ° C, which is helpful for studying luminescence phenomena at low temperatures. In addition, Lexregresearch also supports spatially resolved luminescence measurement and laser stimulation measurement of single mineral particles, which can perform microscopic analysis of solid samples and single mineral particles, providing powerful tools for research in fields such as geology and archaeology. The time-resolved/pulsed luminescence measurement function can not only be used for basic research, but also for IRPL measurement of feldspar, expanding the application range of the equipment.

3、 Enrich modules and expand application boundaries

1. Radiation source: diverse selection, precise irradiation

The Lexsyg series equipment offers multiple radiation source options. The circular beta source can achieve uniform irradiation and is used for radiometric fluorescence measurement; The planar beta source has different activities and dose rates, meeting different experimental conditions. The specially designed Am-241 alpha source has added more possibilities to the experiment. As an alternative to beta sources, X-ray irradiators have the advantages of no radiation when not in use and easier licensing. They can provide different dose rates and are suitable for various dosimetry fields. The built-in Si solid-state photomultiplier tube can monitor dose rate changes in real-time, ensuring experimental accuracy.

2. Optical excitation source: multi wavelength excitation, innovative measurement mode

The optical stimulation module uses five separate LEDs/LDs to ensure uniform illumination of the sample. The output of each LED/LD is monitored in real-time to compensate for aging effects and maintain stable light intensity. The stimulation module can be equipped with up to three wavelengths, supporting multiple measurement modes, and can switch wavelengths multiple times in a single step stimulation, bringing more possibilities to experiments.

3. Filter wheel: precise screening, optimized detection

The filter wheel module has six positions, up to two of which can be installed, making it convenient for users to choose the detection wavelength range. The software will prevent the use of incompatible filters to ensure experimental safety. Lexsyg devices are equipped with specific filter combinations according to user needs to improve detection efficiency.

4. Single particle module: a new perspective for microscopic analysis

The Double Single Particle (SG) module is equipped with green and IR laser diodes for luminescence detection of single mineral particles, which play an important role in studying disturbed sediment or non-uniform radiation field samples.

5. Time resolution/nanosecond pulse module: Capture moments and explore the microscopic world

This module is used for time-resolved luminescence measurement, combined with laser diodes and fast PMT, which can achieve nanosecond pulse stimulation and high-resolution detection. It supports multiple measurement time ranges and detection modes, providing key data for basic research and feldspar dating.

6. Luminescent detector: Multi element detection, comprehensive analysis

6.1. Photomultiplier tube (PMT):Multiple PMT options are available to adapt to different experiments based on wavelength detection range and quantum efficiency.

Typical quantum efficiencies of different PMT (%)

6.2. Charge Coupled Device (CCD):CCD detects luminescence through imaging and can perform spatial analysis on samples. The sensor has a high quantum efficiency of 1024x1024 pixels with a size of 13 × 13 μ m.

It has applications in various measurements and, when combined with relevant software, can achieve more complex data analysis.

6.3. a spectrometer:Spectrometers are used to determine the emission wavelength and provide a basis for optimizing detection conditions. By coupling light to the spectrometer through optical fibers, coupled with adjustable components and different CCD cameras, high-resolution spectral measurement can be achieved.

7. Thoughtful attachments to enhance the experimental experience

7.1. Sample camera:Record details to assist in analysis

7.2. Solar simulator module:Simulate nature and expand research scope

The solar simulator is based on LED arrays and can simulate the spectrum of sunlight or other bleaching light. Bleaching can be carried out at high temperatures because the sample is always placed on a heating plate, and the temperature of the heating plate is monitored to ensure sample safety.

7.3. XRF module:Insight into components, in-depth research

The XRF module can estimate the mineral composition of samples, analyze the proportion of feldspar and quartz contamination, and provide important references for studying sample characteristics.

7.4. Reference light source:Stable monitoring, ensuring accuracy, C-14

7.5. Optical flange:Customized experiments, breaking through limitations

4、 Software assistance, intelligent operation and analysis

LexStudio: Convenient operation, real-time monitoring

LexStudio software is used to operate two devices, store device configuration information, prevent erroneous operations, support remote control, and reduce personnel radiation exposure. It modularizes the operation steps and simplifies complex processes, such as creating SAR/PIRIR measurement sequences. Users only need to set key parameters, and the software can automatically generate them. The measurement data will be saved in XSYG and ASCII formats for real-time monitoring and in-depth analysis.

2. LexEva: Professional analysis, worry free data

LexEva software is used to analyze measurement data and can import data in multiple formats. For SAR analysis of optical stimulated luminescence data, it provides a graphical interface with the R 'Luminescence' package to ensure that the analysis results are based on open source projects and more reliable.