A tricorder is a handheld scanning device in the fictional universe of Star Trek. There are three main variants: the standard tricorder used to give an initial analysis of unfamiliar areas, the medical tricorder used in patient diagnosis, and the engineering tricorder.

A real-world device comparable to the tricorder was developed by the Canadian company Vital Technologies Corporation in 1996. Known as the TR-107 Mark 1, fewer than 2,000 of them were sold before the company went out of business. The TR-107 could scan electromagnetic radiation, temperature, and barometric pressure. A more sophisticated tricorder-like device is being developed at Loughborough University in England, could one day be used to measure blood flow, monitor the heart and assess how well wounds and burns are healing. It involves shining a light on a specific part of the body; potential health problems are identified by measuring how much light is absorbed (see news item below).