Aydogan Ozcan

In a dark room, on a table, sit a laser pointer, a piece of glass with tissue, and an ordinary phone camera. Light passes through the sample, and the image shows not cells but a pattern of bright and dark stripes, like the shadow of leaves on a wall.

A drop of blood from a fingertip lands on the white membrane of a cartridge. Twenty minutes later, the phone shows whether Lyme disease is present or not. No test tube, no centrifuge, no waiting for days. Usually, for such a test, blood is first spun in a centrifuge to separate the liquid part — the plasma.