The Labram system is a confocal Raman imaging microscope system. Both Helium-Neon (632.8nm, 11mW) and Argon ion (514.5nm, 50mW) are available as sources. Both are polarised, enabling measurement of depolarisation ratios and studies of orientation in materials. Light is imaged to a diffraction limited spot (typically 1 micron) via the objective of an Olympus BX40 microscope. The scattered light is collected by the objective in a confocal geometry, and is dispersed onto an air cooled CCD array by one of two interchangeable gratings, 1800 lines/mm or 600lines/nm, allowing the range from 150cm-1 to 4000cm-1 to be covered in a single image, or with greater resolution in a combination of images.
With the former, a spectral dispersion of 1cm-1 per pixel is achievable. The confocal, microscopic system allows measurement of powdered samples with no further sample preparation, direct measurement of liquids and solutions, as well as thin films. Spectral X-Y mapping may be performed with a precision of 0.1 micrometers. The system is furthermore equipped with a remote head which is fibre coupled to the spectrometer.
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