Rice team designs lens-free fluorescent microscope

Lenses are no longer necessary, according to Rice University engineers developing FlatScope, a thin fluorescent microscope whose abilities promise to surpass those of old-school devices.
A paper in Science Advances by Rice engineers Ashok Veeraraghavan, Jacob Robinson, Richard Baraniuk and their labs describes a wide-field microscope as thin as a credit card, small enough to sit on a fingertip and capable of micrometer resolution over a volume of several cubic millimeters.
FlatScope eliminates the tradeoff that hinders traditional microscopes in which arrays of lenses can either gather less light from a large field of view or gather more light from a smaller field.
The Rice team began developing the device as part of a federal initiative by the Defense Advanced Research Projects Agency as an implantable, high-resolution neural interface. But the device's potential is much greater. The researchers claim FlatScope, an advance on the labs' earlier FlatCam, could be used as an implantable endoscope, a large-area imager or a flexible microscope.
"We think of this as amping up FlatCam so it can solve even bigger problems," Baraniuk said.
Traditional fluorescent microscopes are essential tools in biology. They pick up fluorescent signals from particles inserted into cells and tissues that are illuminated with specific wavelengths of light. The technique allows scientists to probe and track biological agents with nanometer-scale resolution.
But like all traditional microscopes, telescopes and cameras, their resolution depends on the size of their lenses, which can be large and heavy and limit their use in biological applications.