MEMS scanner enabled real-time depth sensitive hyperspectral imaging of biological tissue

We demonstrate a hyperspectral and depth sensitive diffuse optical imaging microsystem, where fast scanning is provided by a CMOS compatible 2-axis MEMS mirror. By using lissajous scanning patterns, large field-of-view (FOV) of 1.2 cmx1.2 cm images with lateral resolution of 100 µm can be taken at 1.3 frames-per-second (fps). Hyperspectral and depth-sensitive images were acquired on tissue simulating phantom samples containing quantum dots (QDs) patterned at various depths in Polydimethylsiloxane (PDMS). Device performance delivers 6 nm spectral resolution and 0.43 wavelengths per second acquisition speed. A sample of porcine epithelium with subcutaneously placed QDs was also imaged. Images of the biological sample were processed by spectral unmixing in order to qualitatively separate chromophores in the final images and demonstrate spectral performance of the imaging system.