Diffraction Limit Has Been Beaten

deglr6328 writes "In what is being heralded variously as a "remarkable accomplishment" and a "breakthrough", physicists have reportedly beaten the diffraction limit at optical frequencies. First hypothesized to be possible 30 years ago by Russian physicist Victor Veselago, meta-material "superlenses" with negative refractive indices were first demonstrated around 2001 at microwave frequencies. The use of a thin silver film as an optical superlens in this case, has allowed the team to resolve features less than 40 nanometers wide; 10 times better than any conventional optical microscope. The consequences of the discovery are immediately apparent and include opportunities for extremely fine biomedical imaging in-vivo and greater increases in transistor density for microchips by superlens augmentation of photolithography masks."

Comments

Re:What is diffraction limit?

[denominateur]

http://astrosun2.astro.cornell.edu/academics/cours es/astro201/diff_limit.htm

The calculation shown there is a rough estimate for round openings (hence the 1.22). In essence the resolution of a lense is limited by the wavelength of the light being used and the size of the opening. When the opening is too small, whatever you want to observe is "smudged" due to diffraction effects (the spreading out of waves going through a small aperture). There are two ways to counter this: decrease the wavelength (eg use higher energy light such as xrays) or increase the size of the opening. Both remedies can be problematic since high-frequency light can induce damage and large apertures are sub-obtimal for many applications (especially in semiconductor imaging).

Re:Satellite telescopes?

[madaxe42]

Probably not, no. The major stumbling block in satellite imagery is atmospheric distortion, as you say. Even with adaptive optics and intense post-processing the degree of blur caused by particulate scattering and heat lensing effects cannot be corrected. The only way that I can see this working is if a grid of (high power) infrared lasers, each tuned to a slightly different frequency, were pointed at the target being photographed, in such a fashion that if projected in a perfectly straight line they'd cover it completely with a 1x1 mm resolution or what have you - from where those lasers end up you might be able to do some adapation, but to be honest by the time you'd bounced a laser off the planet and back , and then processed the signal, the conditions would have changed.

So, all in all, no, this won't affect the absolute resolution limit on satellite photography, advances in adaptive optics and post-processing will.

Impact on lense and waveguide design is huge

[metoc]

This pretty much means that the will be a huge amount of R&D put optics, and into redesigning everything from microscope lenses, camera (and cell phone) lenses, to telescope and space based lenses (now the US government can read the fine print on your credit card). Waveguides (read antennas) are also included which means redesigns of antennas for cell phones, wireless internet, radio, and satellites.

Index of refration...

[Spock the Baptist]

http://en.wikipedia.org/wiki/Index_of_refraction

see also Snell's Law,

http://en.wikipedia.org/wiki/Snell%27s_law

Snell's Law: n(a) sin A = n(b) sin B,

where a n(a) is the index of refraction of medium a, and A is the incidence, and n(b) is the index of refraction of medium b, and B is the angle of refraction, where both A, and B are normal with respect to the surface between the two media.

The plane formed by the normal line, and the of incident ray will contain the the refracted ray whether the index of refraction is positive or negative. However, a positive index of refraction will produce a refracted ray that will be measured in the positive direction from the normal line, whereas a negitive index of refraction will produce a refractive ray that has an angle of refraction that is measured measured in the negitive direction from the normal line.

STB
Just adding to the confusion...