'Tractor beam' is possible with lasers, say scientists

'Tractor beam' is possible with lasers, say scientists

A laser can act as a "tractor beam", drawing small objects back toward the laser's source, scientists have said.

It is known that light can provide a "push", for example in solar sails that propel spacecraft on a "wind of light".

Now, in a paper on the Arxiv server, researchers from Hong Kong and China have calculated the conditions required to create a laser-based "pull".

Rather than a science fiction-style weapon, however, the approach would only work over small distances.

The effect is different from that employed in "optical tweezers" approaches, in which tiny objects can be trapped in the focus of a laser beam and moved around; this new force, the authors propose, would be one continuous pull toward the source.

And it relies on directly impinging on an object, making it distinct from an approach demonstrated in 2010 by Australian researchers whose trapping worked by heating air around a trapped particle.

The trick is not to use a standard laser beam, but rather one known as a Bessel beam, that has a precise pattern of peaks and troughs in its intensity.

Seen straight-on, a Bessel beam would look like the ripples surrounding a pebble dropped in a pond.

If such a Bessel beam were to encounter an object not head-on but at a glancing angle, the backward force can be stimulated.

Nice.. First we get the anti laser technology, and now the tractor beam. Coupled with the cloacking technology we are well on our way to a Klingon Bird of Prey.

Now if science can get the whole faster than light travel worked out...

reply to post by Xcathdra


Hehehe... this is still in the stone age compared to the technology employed behind the scenes on this planet. Research joint black military and ET operations to get the ball rolling. You will soon realize any serious scientific progress has been stagnated on the surface long ago...

We could have lasers, free energy, and anything else only limited by the imagination.

Military technology progresses some 40-something years for every civilian year.

reply to post by Mayura


I'm always amazed how earthly scientists keep coming up with these gadgets that mimic UFO activities.

For you youngsters of any age, that relationship concept goes way back to Bell (telephone)
Labs and the supposed "invention" of the transistor. You know, that little thing that was about the size of a match head and replaced vacuum tubes and itself was eventually replaced by thousands of them reduced in size to fit on a small microchip?

reply to post by Aliensun


Yeah, I'm sure the UFO influence goes back some time... It's easy to spot little things like that once your in the know.