We demonstrate a different method to perform near-field Raman imaging with sub-diffraction limit spatial resolution. In this method, a dielectric microsphere (for example polystyrene microsphere) is trapped by optical tweezers. The microsphere is used to focus the laser to the sample, and also to collect the scattered Raman signals. We show the capability of this method in imaging various types of samples, such as SiGe/Si structures, gold nanopattern and carbon nanotubes. This method is comparatively easier to perform, has better repeatability, and generates stronger signal as compared to the normal near-field Raman techniques.
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