New Flat Lens Focuses Without Distortion

yahyamf writes "Applied physicists at Harvard have created an ultrathin, flat lens that focuses light without the distortions of conventional lenses. 'Our flat lens opens up a new type of technology,' says principal investigator Federico Capasso. 'We're presenting a new way of making lenses. Instead of creating phase delays as light propagates through the thickness of the material, you can create an instantaneous phase shift right at the surface of the lens. It's extremely exciting.'" And by "ultrathin," they mean it — 60 nanometers thin. The big advantage for this technology, aimed at telecommunications signals, is that "the flat lens eliminates optical aberrations such as the 'fish-eye' effect that results from conventional wide-angle lenses. Astigmatism and coma aberrations also do not occur with the flat lens, so the resulting image or signal is completely accurate and does not require any complex corrective techniques."

Comments

A return to refractive telescopes?

[a_hanso]

Does this mean that very large refractive telescopes will make sense again? If we sandwich a few of these with the metasurfaces tuned right, could we build a telescope that is a slab instead of a tube? How about telephoto lenses built into camera phones? Or cheaper orbital telescopes?

Re:A return to refractive telescopes?

[ceoyoyo]

"because the temperature difference can distort images during the cooling down phase."

If someone told you that they were either way to credulous or thought you were. You may want to let your camera adjust to the ambient temperature (either cooler or hotter), mostly to avoid condensation, which is a pain to wipe off constantly and will make all your pictures look like you took them in the fog. If you're doing astrophotography you want the sensor to be as cool as possible to decrease the thermal noise. But heating or cooling in a lens on a regular camera doesn't affect the image quality noticeably. Unless of course the lens actually shatters, which I've seen happen, but only growing up in northern Canada.

But if you don't think flexing might be a problem take a piece of plastic wrap, stretch it across a five gallon pail and blow on it. Try and get it tight enough so it doesn't move but also doesn't tear. Now think that this lens is thinner than that.

Co-author checking in.

[Mkoms]

Hi everyone. I'm a co-author on the article, and I'd be happy to answer any questions you may have, though probably tomorrow. I'm hoping that this goes better than the last time I tried this (see here: http://slashdot.org/comments.pl?sid=1747464&cid=33185134), where no questions were asked and most of the discussion centered around mildly funny jokes. I appreciate those as much as the next person, but if anyone likes, we can discuss science =].