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Updated: Jun 16, 2026
08:41
A Rapid Laser Probing Method Facilitates the Non-invasive and Contact-free Determination of Leaf Thermal Properties
Published on: January 7, 2017
Summary
Laser calorimetry for transparent materials requires corrections for temperature distribution. Finite Fourier transforms provide numerical corrections, crucial for large samples and coating absorption loss measurements.
Area of Science:
- Materials Science
- Optical Engineering
- Laser Physics
Background:
- Absorption calorimetry is vital for characterizing transparent materials.
- Laser calorimetry often assumes constant temperature, which can introduce errors.
- Accurate measurement of optical absorption is critical for material performance.
Purpose of the Study:
- To calculate the time-dependent temperature distribution in laser absorption calorimetry.
- To develop numerical corrections for the constant-temperature assumption in laser calorimetry.
- To identify conditions where temperature distribution effects are significant.
Main Methods:
- Utilized finite Fourier transforms to model temperature distribution.
- Applied solutions to derive a correction function for laser calorimetry.
- Analyzed the impact of sample size and coating properties on temperature distribution.
Main Results:
- Developed a method to calculate time-dependent temperature profiles.
- Derived a function for numerical corrections to the constant-temperature assumption.
- Corrections are significant for large-diameter samples.
- Corrections are important when measuring absorption loss of coatings on bulk materials.
Conclusions:
- The constant-temperature assumption in laser calorimetry is not always valid.
- Finite Fourier transform analysis provides essential corrections for accurate measurements.
- Accurate optical absorption data requires accounting for thermal effects in transparent materials and coatings.
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