(CNET) Researchers have come up with a microscopic microscope, tiny enough to fit on a fingertip, that can be cheaply mass-produced and used to scan blood and water for pathogens. The high-resolution microscope functions without the large and expensive lenses usually associated with such imaging devices. Instead, it combines the chip technology found in digital cameras with "microfluidics," the science of channeling liquid at scales far smaller than a common droplet. "The whole thing is truly compact -- it could be put in a cell phone -- and it can use just sunlight for illumination, which makes it very appealing...