Tuesday, July 21, 1998 Published at 22:06 GMT 23:06 UK
A clock the size of a pollen grain
A grain of pollen or a tiny clock?
Scientists at the Sandia National Laboratories in New Mexico have constructed a clock the size of a grain of pollen. Our science editor Dr David Whitehouse reports.
For years Sandia scientists have led the world in building micromachines. Now they've constructed a clock with moving parts the size of a pollen grain.
It is not a mechanical clock with gears and wheels. Rather, it is a minute tuning fork that vibrates. It performs the same job as quartz crystals which are used as timing devices in all electronic components.
This means the micromachines and integrated circuits can be constructed on one chip.
Micromachine technology is already finding applications in computer game joysticks, car stability systems and airbag deployment sensors.
With a new timing device, applications for this technology will continue to grow.
Observed through a high-powered microscope, the device looks exactly like a tiny double-ended tuning fork. It consists of two very fine strings or tines -- 10 would fit on a pinhead -- anchored to a frame the size of a red blood cell.
Because it is so small it vibrates extremely fast and generates frequencies of about 1 MHz. Although this is a relatively low frequency for a computer clock the technology has great potential.