Cover its surface with tiny antennae
Latin word for lentil. And it is indeed true that the shape of bi-convex lenses—the familiar sort used as magnifying glasses—resembles those leguminous seeds. But that resemblance may soon be a thing of the past. For a group of engineers at Columbia University, in New York, led by Nanfang Yu, has worked out how to make magnifying lenses that are flat, and thinner than a hair.
It can do this because its surface is covered with millions of tiny antennae. These antennae are of different designs, each with a cross section smaller than the average wavelength of the light it is interacting with, and are arranged in concentric circles . The antennae scatter the light falling on them in such a way that, when the individual changes are added up, the combined effect is the same as if different parts of the beam had passed through the lens at different speeds.
In practice, few optical systems other than eyeglasses rely on single lenses. Usually, different lenses with different properties are stacked on top of each other to remove aberrations and achieve full-colour wide-angle images. Dr Yu’s lenses can be stacked in this way, too. By sandwiching three of them together, he has created a triplet that achieves almost all the control of light waves that would be expected of bigger and heavier glass-lens systems.
Flat lenses still need development before they can truly replace their glass counterparts. In current designs, only around half of the light falling on a flat lens triplet makes it through to the other side. The rest is reflected or absorbed by the material. In a typical glass lens, by contrast, at least 90% of the light passes through. However, the researchers hope that, by tweaking the shapes and positions of the antennae, they will be able to improve on this.
Indonesia Berita Terbaru, Indonesia Berita utama
Similar News:Anda juga dapat membaca berita serupa dengan ini yang kami kumpulkan dari sumber berita lain.
Why Meghan Markle Decided Not to Cover 'British Vogue'Meghan Markle guest edited the September issue of 'British Vogue,' but decided not to appear on the cover -- here's why:
Baca lebih lajut »
Here's the Cover of the 'British Vogue' Issue Meghan Markle Guest-EditedThe Sussex Royal account just posted the cover of the British Vogue magazine cover that Meghan Markle is guest-editing. Not only that, but there's a first photo of Meghan!
Baca lebih lajut »
https://people.comGet the latest news about celebrities, royals, music, TV, and real people. Find exclusive content, including photos and videos, on PEOPLE.com.
Baca lebih lajut »
This 'Mean Girls'-Inspired Cover of Taylor Swift's 'Mean' Is So Fetch'You pointed out my flaws again when you wrote it in your burn book!'
Baca lebih lajut »
https://people.comGet the latest news about celebrities, royals, music, TV, and real people. Find exclusive content, including photos and videos, on PEOPLE.com.
Baca lebih lajut »
15 stars Meghan Markle picked for her Vogue cover and the reasons she chose themMeghan Markle is in charge of the September issue of the legendary magazine and she has made some crucial decisions
Baca lebih lajut »