The scattering parameters of a medium and the imaging resolution have a complementary relationship with the wavelength of the incident light. If the wavelength of the light is increased, photons penetrate deeper into the scattering medium; however, the imaging resolution decreases due to the diffraction limit. Decreasing the wavelength of the light improves the imaging resolution at the cost of decreased depth-of-penetration. We propose to employ multiple wavelengths to get best of both the worlds where we can image deeper, and also at better resolutions. In the past, the team demonstrated subsurface vein imaging enhancement using multi-spectral light and structured light.
Subsurface Vein Imaging Enhancement [Click here for more details]
Direct/global image separation is achieved through the use of high-frequency coded illumination patterns – in this context, a high-frequency checkerboard. After several images are taken of this illumination at different shifts across the scene, the direct and global components are computationally reconstructed.