Researchers at the California Institute of Technology have developed a "microscope on a chip" that is small and can be produced very inexpensively. The Science daily, July 29, 2008 claims that it can be mass-produced at around $10.

Because this device is small, has no lens to break, and can be produced at low cost the potential applications for this new microscope are exciting. You could, for instance, develop a microscope that could fit in a cell phone sized devide. Such a device would, amoung other things, help field workers in undeveloped countries to check for malaria or for hikers to check for microbes.

The developer is Changhuei Yang, an assistant professor of electrical engineering and bioengineering at California Institute of Technology. Changhuei Yang commented, "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 for Third-World applications."

The way the chip works is actually simple. The device has a thin layer of metal with tiny holes punched into it at about 5 micrometers apart. There is a sensor aray to which the metal is coated that is similer to sensor arrays used in digital cameras. Each hole matches to one pixel. A microfluidic channel, which is where the liquid containing samples will flow, is on top of this metal and sensor array. Objects that pass through the channel block light and a series of images are created, like a pinhole camera. All the images are then pieced together.