Raman imaging is a powerful technique for generating detailed chemical images based on a sample’s Raman spectrum. A complete spectrum is acquired at each and every pixel of the image, and then interrogated to generate false colour images based on material composition and structure:
- Raman peak intensity yields images of material concentration and distribution
- Raman peak position yields images of molecular structure and phase, and material stress/strain
- Raman peak width yields images of crystallinity and phase
Thus with a single data set a wide variety of Raman images can be created which take the researcher well beyond what the eye can see.
Standard point-by-point mapping affords the ultimate sensitivity for materials with extremely low Raman scattering properties, and additionally allows high resolution, large spectral range capability. Typical acquisition times for such maps can be in the order of 1s-10s per point (or longer), and thus total measurement times can be significant. The LineScan and SWIFT™ Ultra-fast Raman Imaging modules offer drastically reduced measurement times with acquisition times down to <5ms/point, allowing large area survey scans and detailed Raman images to be completed in seconds or minutes!
The latest developments in Raman imaging offer adaptive laser spot sizes for true macro-scale Raman imaging using the unique DuoScan™ optics. In addition, combination of Raman imaging with piezo stages (including the DuoScan™ module) and AFM systems is moving Raman imaging far into the sub-micron regime, making Nanoscale Raman imaging a reality at last.