Risø vs. Lexsyg: Technical Comparison of TL/OSL Reader Systems

Posted by Rotunda Scientific on

Overview

For years, the Risø DA-20 TL/OSL Reader has been the most widely recognized instrument in luminescence dating and retrospective dosimetry. It’s familiar, reliable, and has a long track record. But as research has advanced, so have the demands placed on instruments. The Risø’s fixed protocols, limited stimulation options, and single-detector setup now restrict what many labs want to accomplish (Risø Reader Documentation).

That’s why more researchers are turning to the Lexsyg Smart and Lexsyg Research from Freiberg Instruments. These next-generation readers were designed to overcome the limits of older systems—delivering programmable heating, modular stimulation, advanced detection, and homogeneous irradiation (Freiberg Instruments; Rotunda SciTech).

  • Lexsyg Smart: a space-saving, versatile system that balances reliable throughput with flexibility for method development.
  • Lexsyg Research: a modular flagship platform for innovation, offering advanced detection (including EMCCD for imaging), multi-wavelength stimulation, and highly uniform irradiation fields.

Where Risø represents the legacy standard, Lexsyg represents the future of luminescence science.

Key Technical Advantages of Lexsyg

Programmable Heating & Cooling

  • Lexsyg: Linear and non-linear heating/cooling ramps, 0.1–20 °C/s, Tmax ~710 °C. Enables advanced protocols not possible with legacy systems (Freiberg Instruments).
  • Risø: Linear heating only, limited control (Risø Reader Documentation).

Optical Stimulation

  • Lexsyg: Modular OSL units with up to three wavelengths per unit (UV through IR, LED or laser). Supports CW-OSL, LM-OSL, POSL (Rotunda SciTech).
  • Risø: Fixed stimulation—blue (~470 nm) and IR (~870 nm) LEDs. Minimal options for expansion (Risø Reader Documentation).

Detection & Imaging

  • Lexsyg Smart: Single PMT detection with filter switching.
  • Lexsyg Research: Up to four detectors, including PMTs, spectrometers, and EMCCD cameras for single-grain and spatially resolved luminescence (Freiberg Instruments).
  • Risø: Single PMT only.

Irradiation Sources & Dose Homogeneity

  • Lexsyg Smart: Planar and ring beta source.
  • Lexsyg Research: Planar and ring beta source deliver dose uniformity to ±2.5% across 8 mm (Richter et al., Geochronometria). Alpha and X-ray options also available.
  • Risø: Fixed on-plate beta source (Risø Reader Documentation).

Sample Capacity & Workflow

  • Lexsyg Smart: 40-position changer with dual exchangeable carousels; separate storage and measurement chambers prevent cross-talk, a 50 sample wheel is also available for use with smaller sample cups of 0.8 cm LexStudio provides programable workflow with easy select and insert process steps. (Rotunda SciTech).
  • Lexsyg Research: 80-position changer—samples can be loaded/unloaded during analysis. LexStudio provides programable workflow with easy select and insert process steps.. (Freiberg Instruments).
  • Risø: 48-position changer, functional but less efficient (Risø Reader Documentation).

Comparison Table

Feature Risø DA-20 Lexsyg Smart Lexsyg Research
Heating / cooling Linear heating, limited control (to ~700 °C) Programmable non-linear ramps; 0.1–20 °C/s, Tmax ~710 °C Same flexibility, extended options for advanced studies
OSL stimulation Fixed Blue (470 nm) + IR (870 nm) Up to 3 modular units (UV–IR, LED or laser) Expanded modular set, interchangeable
OSL modes CW, LM (POSL optional) CW, LM, POSL CW, LM, POSL, advanced configs
Detection Single PMT PMT with filter switching PMTs, spectrometer, EMCCD (imaging)
Irradiation sources Fixed beta source Planar beta (standard); optional ring variants Ring beta, planar, alpha, X-ray
Dose field uniformity Stable, well-characterized ±2.5% with ring source (high homogeneity) ±2.5% with ring source (high homogeneity)
Sample handling 48-position changer 40-position carousel; separate storage & measurement 50-position optional with smaller sample size  80-positions carousel; Load/unload during analysis; modular storage
Best suited for Routine luminescence dating; retrospective dosimetry with standard protocols Flexible labs handling varied minerals, small-scale archaeology & geology studies, radiation physics Advanced archaeology & geochronology, dosimetry R&D, single-grain and spatial luminescence imaging, material science and semiconductor material research

Usage Considerations

Lexsyg Smart

  • A compact yet powerful system for labs that need routine throughput with flexibility.
  • Well-suited for small-scale archaeology and geology studies, radiation physics, and labs analyzing varied minerals.

Lexsyg Research

  • A flagship platform for advanced research applications and larger scale throughput
  • Excellent for archaeology and geochronology, dosimetry development, and single-grain or spatially resolved luminescence imaging thanks to its ring-source irradiation and EMCCD options. Very well suited for material research and semiconductor material analysis.

Risø DA-20

  • Best suited for routine luminescence dating and retrospective dosimetry under standard protocols.
  • A familiar legacy platform, but increasingly limited compared to modern alternatives.

Key Tips for Lexsyg Users

  • Calibrate across different grain-size fractions and aliquot sizes to minimize dose-rate uncertainty (GChron).
  • Use ring beta irradiation sources for high uniformity when precision is critical (Geochronometria).
  • Take advantage of multi-wavelength stimulation options to optimize signal sensitivity across different minerals (Freiberg Instruments).

Conclusion

The Risø DA-20 has served luminescence science well, but its design reflects an earlier generation. For labs that want to push their research forward, the Lexsyg Smart and especially the Lexsyg Research provide programmability, modularity, and advanced detection options that open new possibilities in luminescence dating and dosimetry.

Lexsyg Product Page

References & Further Reading

This article was written in part with the assistance of AI to help organize, summarize, and reference publicly available information.

Share this post

← Older Post Newer Post →