Fast wide-field Raman spectroscopic imaging based on simultaneous multi-channel image acquisition and Wiener...

Raman spectroscopic imaging is a powerful label-free tool for studying cells and tissues in biology and medicine, but it suffers from extremely slow data acquisition. In this Letter, a novel multi-channel Raman imaging technique is proposed to speed up Raman acquisition. Wide-field Raman images are taken in multiple narrow-band channels, each through a different bandpass filter, simultaneously in one camera frame. Then Wiener estimation is used to quickly reconstruct the full Raman spectrum at each pixel from narrow-band measurements. The proposed system with four channels was evaluated in the mixtures of two and three chemicals exhibiting strong Raman scattering because of convenience in the verification of reconstructed spectra. This new technique is expected to overcome the limitation of traditional Raman spectroscopic imaging in speed, and expand its applications in the label-free analysis of both biological and non-biological samples, where potential species are known and fast imaging is required to investigate temporally varying events.