Pocket atomic clock

03 May 2013

London watchmaker Hoptroff has produced the world's first watch with true atomic-clock accuracy.

Several manufacturers already offer affordable watches that synchronise to the radio signals transmitted from atomic clocks around the world, but Hoptroff's 'No.10' movement is different because it actually features a miniature atomic clock of its own. A first production run of only 12 seagoing-style pocket watches for collectors is intended.

Hoptroff No.10 movement
The back and the front of the Hoptroff No.10 movement and a potential face for the watch

The watch will use a Quantum SA.45s 'chip scale atomic clock' developed by Symmetricon for military applications in drones and cruise missiles. Despite being only around 4.1 cm across and 1.1 cm thick, this contains caesium gas at a controlled temperature, a laser exciter and a microwave resonator that combine to stimulate the caesium, measure its vibrations and mark the passage of time.

Researched and written
by World Nuclear News