Real-life 'tractor' beam allows ray of light to attract objects

Light manipulation techniques have existed since the 1970s, but the University of St Andrews said this is the first time a light beam has been used to draw objects towards the light source, albeit at a microscopic level.

Researchers from the University of St Andrews and the Institute of Scientific Instruments (ISI) in the Czech Republic have found a way to generate an optical field that efficiently reverses the radiation pressure of light.

The new technique could lead to more efficient medical testing, such as in the examination of blood samples.

In the US science-fiction show Star Trek, a tractor beam was a method of using a beam of light that could pull spaceships and other large objects towards the source of the light.

The team, led by Dr Tomas Cizmar, research fellow in the School of Medicine at the University of St Andrews, with Dr Oto Brzobohaty and Prof Pavel Zemanek, both of ISI, discovered a technique that will allow them to provide ‘negative’ force acting upon minuscule particles.