dhm2Images of micrometer-scale colloidal spheres created with holographic video microscopy incorporate comprehensive information on each particle’s three-dimensional position, its size, and its complex-valued refractive index.  NYU’s Holographic Characterization team uses state-of-the-art techniques in image analysis to extract all of this information for each particle in the accessible volume of a holographic microscope, for each snapshot in a holographic video stream.  These analyses yield the position of a micrometer-scale particle to within a nanometer, the radius to within a nanometer, and the refractive index to within a part per thousand.  No other technique provides such a wealth of particle-resolved data.  Applications of holographic characterization include product development, process control and quality assurance in industries as diverse as food, personal care products, pharmaceuticals, surface coatings and cosmetics.mixture1

The video shows the hologram of a colloidal sphere diffusing as it sediments through water, together with a frame-by-frame fit to predictions of the Lorenz-Mie theory of light scattering.  The plot on the right shows the particle’s reconstructed trajectory in three dimensions.



Moore Sloan Poster Research Project