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Updated: Jul 9, 2026
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Characterization of Biological Absorption Spectra Spanning the Visible to the Short-Wave Infrared
Published on: January 10, 2025
Glasses for seeing beyond visible.
XiangHua Zhang1, Bruno Bureau, Pierre Lucas
1Laboratory of glasses and Ceramics, UMR 6226 CNRS-University of Rennes, 35042 Rennes, France.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|December 11, 2007
Summary
New infrared (IR) glasses, particularly telluride-based ones, offer extended transparency for thermal imaging and molecular analysis. These advancements enable applications from car-driving assistance to space exploration for signs of life.
Area of Science:
- Materials Science
- Optics
- Spectroscopy
Background:
- Conventional oxide glasses have limited infrared transparency due to phonon absorption.
- The infrared (IR) spectrum is crucial for thermal imaging and identifying molecular vibrational signatures.
- Advances in IR detectors are paralleled by progress in IR glass optics, including lenses and fibers.
Purpose of the Study:
- To discuss the development of new IR glass compositions for cost-effective lenses.
- To highlight the use of IR optical fibers for in situ spectroscopy.
- To explore applications in environmental monitoring, biomolecular analysis, and astrobiology.
Main Methods:
- Development of chalcogenide glasses (sulfide, selenide, telluride) with extended IR transparency.
- Structural considerations for designing new glass compositions.
- Fabrication of multimode and single-mode IR optical fibers.
Main Results:
- Chalcogenide glasses exhibit transparency up to 12 (S), 16 (Se), and 28 micrometers (Te).
- These glasses cover atmospheric transparency windows (3-5 and 8-13 micrometers) for thermal imaging.
- IR spectroscopy with optical fibers is applied to environmental and biomolecular analysis.
Conclusions:
- IR glasses, especially telluride-based, are vital for advanced optical applications.
- IR spectroscopy using novel fibers enables sensitive molecular detection.
- These technologies support diverse fields from automotive safety to the search for extraterrestrial life.
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