Metamaterial 'hyperlens' has potential for early cancer detection

Researchers investigating the optical properties of metamaterials claim to have created a lens which can potentially image single molecules and to detect cancerous cells. Made of minute slivers of gold and a transparent polymer, the lens works with visible light and is claimed to avoid the problems of refraction seen with conventional optical lenses.

Conventional optics reach the limit of their usefulness when the objects they are being used to study are of a similar scale to the wavelength of the light being used to illuminate them. Metamaterials — which have optical properties not found in nature — can avoid this problem by converting so-called ‘evanescent’ waves of light, which results from diffraction and is lost in conventional optics, into propagating light that can be collected and transmitted with standard equipment. Known as hyperlenses, early versions of these systems were composed of concentric rings of silver and an insulating material; the lens would be formed by slicing a complete circle of these rings along a diameter, with the light then entering along the curved side. However, these hyperlenses only worked with a narrow range of wavelengths and suffered large losses.