Material Characterization

Reflection spectroscopy – also known as ‘reflectance spectroscopy’ – is often used to characterize objects and materials non-invasively and non-destructively. Comparing the reflected light to the light used for illumination can tell you a lot about the characteristics and nature of the object or material being researched, for instance, exact colors, compounds, and more.

When light hits the surface of a material, it will either be reflected, absorbed, or transmitted through the material (or a combination of the above). The reflectance of this light will depend on the object’s structure and material properties.

Depending on the reflectance application, a wide variety of light sources, accessories, fiber-optic probes, and spectrometers can be chosen, offering you a tailor-made solution for your specific application.

Configuring a Setup

Since reflection measurements can be performed in a reasonably broad wavelength range, Avantes offers several spectrometers suited for reflection measurements in the wide range of 200 to 2500 nm. The most common option for reflection measurements is the AvaSpec-ULS2048CL-EVO, configured from the UV to the near-infrared spectrum.

Multi-channel configurations can also broaden the range even further. This allows you to measure in a broad wavelength while maintaining high resolution and sensitivity.

Depending on the application, accessories for reflection measurements can range from integrating spheres to various reflection probes and collimating lenses. We also offer a reflection stage to measure small samples easily.

Colour Measurements

We humans can see color and differentiate between objects thanks to light’s reflectance. One of the most prevalent uses for reflectance spectroscopy is color measurement. Color measurements are used in various industrial applications, such as determining the color of textile, paper, fruit, wine, and bird feathers.

Spectrometers are designed to measure exact wavelengths and are ideal for color measurements. Visible light has a wavelength range of 390-750 nm, so generally, color measurement systems are configured to cover the range from 380-780 nm with a spectral resolution of around 5 nm (FWHM).

reflection probe or integrating sphere with a halogen light source is typically required to facilitate reflective color measurements. In either case, a white continuous light source illuminates the surface to be measured, and a white reflective standard tile is needed for calibration.

Avantes has developed a variety of custom reflection probes to meet the specific demands of different color measurement applications. Color measurements are manifested in the L*a*b* color model, which includes parameters for brightness and hue. This and other presets for color measurements can be found in our AvaSoft color application software.

We have developed two bundles for standard color measurement applications: one for small areas and one for surfaces. Both bundles feature the AvaSpec-ULS2048CL-EVO spectrometer but offer other light sources and accessories.

Colour Measurement Video

These are some of the products mentioned above. Contact one of our sales engineers for advice to find the perfect setup for your specific application.

Application Examples

Below are detailed application notes on various uses of reflection spectroscopy in different applications and industries.

Why choose Avantes for your reflection application?

  • Multi-channel capabilities to measure broad wavelength ranges
  • Extensive knowledge on reflection and colour measurements, setups, accessories, and software
  • Wide selection of reflection probes for various purposes

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