Confocal Raman Microscopy

Confocal Raman Microscopy/Spectroscopy (CRM) brings together confocal imaging and Raman spectroscopy to provide capabilities not available to either Fourier transform infrared (FTIR) spectroscopy or the scanning electron microscope (SEM). CRM’s high resolution also fills a dimensional measurement gap between those two techniques. The confocal imaging system provides a spectral image with the capability to produce spatial resolution down to 440 nanometers.

CRM’s high resolution allows laser-illuminated Raman spectroscopy to focus on very tightly defined sample areas. This dramatically improves the ability to identify molecular-level components of both organic and inorganic samples. Furthermore, allowing the identification of specific sample areas to be identified accurately.

CRM’s digital Raman spectroscopy data can be stored and processed to reduce the effect of background-noise pollution in the electronic systems. That allows more accurate interpretation of noisy spectral data from trace components.

Because laser-illumination energy can penetrate the surface of samples, CRM can also reveal Raman spectroscopic data from subsurface layers. The confocal imaging system allows precise control of the depth where the spectroscopic data is acquired. This depth control (Z-axis imaging) allows layered samples to be analyzed without cutting cross-sections.

CRM Applications

Our experts provide a wide spectrum of Raman analysis and Raman mapping applications. Raman analysis is an ideal technique for the qualitative and semi-quantitative analyses of organic and/or inorganic mixed materials. Samples analyzed by Raman spectroscopy include proteins, polymers, pharmaceuticals, minerals and other inorganics.

• Identification of organic and inorganic materials, polymers, and biomolecules in particles, defects and bulk materials

• The determination of the presence of different carbon types including diamond, graphitic, nanoparticles and nanotubes, diamond-like carbon and amorphous carbon

• Characterization of crystalline structures and stresses in semiconductors and polymers

• Raman mapping analysis of the distribution of components in mixtures such as active pharmaceutical ingredients in excipients, tablets and drug-eluting stent coatings

Benefits of Raman Spectroscopy Techniques:

Wide Range of Raman Microscopy and Mapping

• Polarization analysis for measuring molecular orientation
• Confocal Raman microscopy with 532nm and 785nm laser excitation
• Non-destructive depth profiling
• Analysis of microscopic samples (small and large areas)
• Automated spectral mapping with motorized stage
• Mapping and imaging for characterization of chemical composition, crystallinity, orientation, strain, additive migration, etc.
• Coating characterization, cure, stratification, uniformity, etc.

In summary, Raman mapping and imaging analysis provides a spectral image with consistent resolution of 200 nanometers. Raman analysis allows laser-illuminated Raman spectroscopy to focus on very tightly defined sample areas, dramatically improving the ability to identify molecular-level components of both organic and inorganic samples.

In Raman analysis, the laser-illumination energy can penetrate the surface of translucent samples, yielding a Raman scattering signal from subsurface layers. The confocal imaging system allows precise control of the depth where the spectroscopic data is acquired. This depth control (Z-axis imaging) allows layered samples to be analyzed without cutting cross-sections.

Raman Mapping of a Tablet

Photo: Tablet prior to Raman mapping

Photo: Raman mapping analysis of component distributions in a tablet. Each color represents one ingredient. The color map shows the composite of five ingredients.

Other Applications for Raman Imaging

Click thumbnail to enlarge image.

At MVA Scientific Consultants, we provide our customers with a full range of Raman analyses to test and analyze small contamination areas, identify materials in small target areas, and measure stress in a variety of materials.

For more information, email info@mvainc.com or call 770-662-8509.