A working motor powered only by laser light has been demonstrated by researchers at the International Christian University in Tokyo, Japan. Light-powered motors will work in areas with high magnetic fields unsuitable for conventional motors, such as such as MRI medical scanners.
The announcement bodes well for designers of medical and industrial machinery which currently require heavy, expensive shielding for their electric motors. It also gives a boost to research into nanotechnology as initially laser-powered motors will be exceptionally tiny - on the molecular scale, in fact.
In the following video, each colored ball represents a single atom:
The prototype laser-powered motor features a copper disc with a hole in the middle - much like a very tiny washer. When green laser light with a wavelength of precisely 532 nanometers is fired at the disk, the metal heats up and expands.
The result of this rapid expansion is that a series of tiny, fast-moving elastic waves move across the surface of the disk in a circular motion around the ring's center of the ring. By mounting the disc on a spindle, it will begin to rotate much like a conventional motor.
Physicist Hideki Okamura heads the research team at International Christian University says that experiments with laser-powered "tweezers" inspired him to further investigate laser light as a technique for moving solid objects. Although the new motor lacks a reverse gear, Okamura is testing methods of controlling both the speed and the direction of the motor using materials that respond in various ways to different laser frequencies. (via NewScientistTech)
Japanese Innovations Writer