Researchers at the University of Houston have created an optical lens that can be placed on an inexpensive smartphone to amplify images by a magnitude of 120, all for just 3 cents a lens. The lens can work as a microscope, and the cost and ease of using it – it attaches directly to a smartphone camera lens, without the use of any additional device – make it ideal for use with students. It also could have clinical applications, allowing small or isolated clinics to share images with specialists located elsewhere.

(a) Changing the temperature of the preheated surface modifies the shape of a cured lens, (b) the inkjet print head printing droplet lenses on a heated surface, and c) the lens can be attached to a smartphone for microscopy applications.

The lens is made of polydimethylsiloxane (PDMS), a polymer with the consistency of honey, dropped precisely on a preheated surface to cure. Lens curvature depends on how long and at what temperature the PDMS is heated. The resulting lenses are flexible, similar to a soft contact lens, although they are thicker and slightly smaller.

Because the lens attaches to a smartphone, it’s easy to share images by email or text, and because the lenses are so inexpensive, it wouldn’t be a disaster if a lens was lost or broken.