Seeing objects smaller than the wavelength of light, such as viruses, typically requires scanning electron (SEM) or stimulated emission depletion (STED) microscopes. These are bulky technologies that are expensive and impractical for use outside a laboratory.
A new technology in the form of a smartphone case from researchers at UCLA now offers the ability to visualize fluorescent tagged viruses and nanoparticles down to 100 nanometers in diameter.The system shines a laser light at 75° onto the sample and a special color filter is used block scattered light that would otherwise fuzzy-up the image. The remaining light is captured by the smartphone camera and results show up right on the screen.
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