Edwin L. Aguirre
Imagine a camera system capable of taking images of microscopic objects at very high resolution without using lenses.
That’s what physics Assoc. Prof. Viktor Podolskiy hopes to accomplish, thanks to a three-year $261,265 grant from the National Science Foundation.
“What my graduate students and I are trying to do is to develop a fundamentally new approach to imaging and focusing of light that would eliminate the need for bulky optical components, such as lenses or mirrors, and provide dramatic improvement in resolution,” says Podolskiy.
In contrast to conventional electronic cameras that use lenses to form a direct image of an object on their CCD sensor, Podolskiy plans to use a pre-designed structure — similar to a diffraction grating — that would form a scrambled diffraction pattern, or “interferogram,” of the object on the CCD.
“The imaging system becomes more compact, but the price you pay for it is the need to use special algorithms to process the interferogram in order to recover the image,” he says. “It’s sort of like what is being done with computer-assisted tomography, or CAT scans, in hospitals.”
He says if this technique works — and he and his team have a good indication that it does — they can do several very exciting things.
“First, we can recover the image of very small objects down to one-twentieth of the wavelength of light — something that can only be done right now with near-field scanning microscopy,” he says. “We are talking about improving the speed of microscopic examination and opening the door for observing relatively large viruses in their environment in real time. Second, we can potentially use this technique to dramatically miniaturize thermal, or mid-infrared, cameras.”
Podolskiy says their research presents an opportunity to use recent advances in computing, materials science and fabrication to revolutionize the full spectrum of imaging systems, from tabletop microscopes to portable cameras and telescopes, affecting the lives of researchers and ordinary people alike.