Method and system for active-illumination parallel Raman microspectroscopy

A versatile optical platform for full-spectrum imaging ("hyperspectral") microscopy with integrated optical tweezers and traps is disclosed. This design strikes the optimum balance between efficient light utilization and agile "point-and-shoot" imaging. This imaging system has several significant advantages over conventional microscopy scanning schemes in terms of sparse and adaptive sampling with respect to spatially-varying information density, diffraction-limited efficiency of excitation light utilization, computationally enabled for compressive sensing algorithms and full-spectrum recording with high resolution (both spatial and spectral). The disclosed platform is versatile for nearly every hyperspectral microscopy scheme, including, but not limited to, One or multi-photon fluorescence, Infrared, Near-infrared, UV/visible, Raman, Surface-enhanced Raman, Light scattering, Localized surface plasmon resonance, Surface plasmon resonance, Dark-field and etc. Briefly, an excitation light pattern is projected onto the sample by a phase spatial light modulator such as a programmable liquid crystal on silicon (LCOS) microdisplay. The "excited" pattern is then recorded by a synchronized imaging spectrograph with a camera detector. Besides diffraction loss, there is no additional optical loss mechanism and thus maximize light utilization efficiency. By changing the projected patterns, full-spectrum microscopic imaging can be performed with sparse and adaptive sampling to maximize throughput. Wnen a high-power light source is used in coni unction with tightly focusing microscope objectives, the projected dot patterns become effective optical tweezers and traps. This scheme can track or manipulate micro/nanoparticles while recording their full-spectrum simultaneously. To demonstrate the new concept, we have built a prototype system based on Raman spectroscopy and show that the disclosed design can indeed achieve what are claimed.

App TypeCase No.CountryPatent/Publication No.
InquireNational Phase2012009United States8,902,421