Material makes backwards lens

Left-handed materials bend light in the opposite direction as conventional materials, giving them useful new optical qualities.

Researchers from the University of Toronto have constructed a prototype lens composed of a network of wires and tiny split rings that causes microwaves to have a negative bend, or index of refraction.

The material affects waves of a relatively wide frequency in the useful communications range of 1 to 2 gigahertz, and could lead to imaging applications, devices that focus antenna beams for surveillance applications, and smaller, higher bandwidth cellphone components, according to the researchers.

Previous research brought this type of left-handed material to light; the Toronto researchers took the research a step further by demonstrating that a negative refraction material can be used to construct a useful lens.

Similar lenses that affect visible light are also possible, according to the researchers. Such materials could more closely focus light in order to etch smaller electronic devices, according to the researchers.

Left-handed radio frequency/microwaves could be used in practical applications within a year, and visible light applications in two to three years, according to the researchers. The work appeared in the March 19, 2003 issue of Applied Physics Letters.