Ion trap from optical atomic clock developed at the National Physical Laboratory. This unit is the 'flight spare' made by Professor Patrick Gill and his team as a display and demonstration device, and is physically identical to the trap used in the clock from 2005.

An optical frequency ion-trap clock is one of the most accurate clocks yet made, and when fully realised will be inherently more accurate than caesium atomic clocks which use microwave frequencies. The ion trap itself is the heart of the clock, a device for trapping single ions (charged atoms) in a force field, then blasting them with laser beams to extract time and frequency information.