minduploading.org News: Perfect Lenses?
- Dr. Pendry postulates the properties of lenses made with materials that have a negative refractory index and subsequently may permit the construction of perfect lenses at any wavelength of light. If this works, it could be of hugh value to whole brain emulation. Imagine extreme precision at long wavelengths! This could reduce the damage to a sample, possibly even aid in the development of non-invasive high-resolution scanning devices.
"Lens design: A sharper focus"
"THEORETICAL physicists have a knack of asking ``why not''
Antimatter was discovered because a theoretician called
Paul Dirac saw that one of his equations had two solutions: one
with a plus sign that predicted normal negatively charged
electrons, the other with a minus sign that predicted a
curious positively charged beast."
"In similar vein, John Pendry of Imperial College, London has been
asking what happens if a material's refractive index, which
measures how much it bends a ray of light or other form of
electromagnetic radiation, is negative instead of positive --
an idea that folk familiar with practical optics might dismiss as
"Dr Pendry's calculations for a material with a negative
refractive index, rather like Dirac's for the electron, have two
solutions -- and the second allows near-field waves to grow
instead of decaying. In the right circumstances this effect can
exactly balance out the decay, ensuring that all the information
is restored in a perfect image of the source. The wavelength of
visible light is a fraction of a millionth of a metre, which
sets a resolution limit for conventional optical microscopes.
But with negative-refractive-index lenses, this limit could be
"Earlier this year, Sheldon Schultz at the University of California,
San Diego, showed that a specially designed material made of wires
and rings had a negative refractive index in the microwave region.
Meanwhile Dr Pendry and his colleagues at Hammersmith Hospital in
London, along with GEC Marconi, an electronics company, have
designed a negative-refractive-index lens for radio waves on the
"The technique remains unproven, but early efforts by Dr
Pendry and his colleagues seem promising. And Dr Pendry already
has ideas about how to build lenses that would do the same job
in the optical region. For generations of scientists, the
diffraction limit was seen as a fundamental barrier to progress
in optics, so news of perfect lenses will come as a shock
to some. But then, so did antimatter."
Complete Story: http://www.economist.com/science/displayStory.cfm?Story_ID=417791
RANDAL A. KOENE
Neural Modeling Lab, Department of Psychology - McGill University
minduploading.org, Lab:(514)-398-4319, Home:(514)-767-6406