科研人员发明检测赫兹辐射的新镜头
文章来源:未知 文章作者:enread 发布时间:2016-03-15 05:39 字体: [ ]  进入论坛
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Terahertz radiation is a relatively1 unexplored slice of the electromagnetic spectrum2, but it holds the promise of countless3 new imaging applications as well as wireless4 communication networks with extremely high bandwidth. The problem is that there are few off-the-shelf components5 available for manipulating terahertz waves. Now, researchers from Brown University's School of Engineering have developed a new type of lens for focusing terahertz radiation (which spans from about 100 to 10,000 GHz). The lens, made from an array of stacked metal plates with spaces between them, performs as well or better than existing terahertz lenses, and the architecture used to build the device could set the stage for a range of other terahertz components that don't currently exist.
 
The work was led by Rajind Mendis, assistant professor of engineering (research) at Brown, who worked with Dan Mittleman, professor of engineering at Brown. The work is described in the journal Nature Scientific Reports.
 
"Any photonic system that uses terahertz - whether it's in imaging, wireless communications or something else - will require lenses," said Dan Mittleman, professor of engineering at Brown and the senior author on the new paper. "We wanted to look for new ways to focus terahertz radiation."
 
Most lenses use the refractive properties of a material to focus light energy. Eyeglasses, for example, use convex glass to bend visible light and focus it on a certain spot. But for this new terahertz lens, the properties of the materials used don't matter as much as the way in which the materials are arranged.
 
"It's the architecture here that's important," Mendis said.
 
The new device is made from 32 metal plates, each 100 microns thick, with a 1-millimeter space between each plate. The plates have semicircular notches6 of different sizes cut out of one edge, such that when stacked horizontally the notches form a three-dimensional divot on one side of the device. When a terahertz beam enters the input7 side of the device, slices of the beam travel through the spaces between the plates. The concave output side of the device bends the beam slices to varying degrees such that the slices are all focused on a certain point.
 
Using the configuration8 developed for this new study, the researchers were able to focus a two-centimeter-diameter terahertz beam down to a four-millimeter spot. The radiation transmission through the device - the amount of radiation that makes it through the spaces as opposed to reflected back toward the source or dissipated inside the device - was about 80 percent. That's significantly better than silicon9 lenses, which typically have a transmission loss of about 50 percent, and about the same as lenses made from Teflon.


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1 relatively bkqzS3     
adv.比较...地,相对地
参考例句:
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
2 spectrum Trhy6     
n.谱,光谱,频谱;范围,幅度,系列
参考例句:
  • This is a kind of atomic spectrum.这是一种原子光谱。
  • We have known much of the constitution of the solar spectrum.关于太阳光谱的构成,我们已了解不少。
3 countless 7vqz9L     
adj.无数的,多得不计其数的
参考例句:
  • In the war countless innocent people lost their lives.在这场战争中无数无辜的人丧失了性命。
  • I've told you countless times.我已经告诉你无数遍了。
4 wireless Rfwww     
adj.无线的;n.无线电
参考例句:
  • There are a lot of wireless links in a radio.收音机里有许多无线电线路。
  • Wireless messages tell us that the ship was sinking.无线电报告知我们那艘船正在下沉。
5 components 4725dcf446a342f1473a8228e42dfa48     
(机器、设备等的)构成要素,零件,成分; 成分( component的名词复数 ); [物理化学]组分; [数学]分量; (混合物的)组成部分
参考例句:
  • the components of a machine 机器部件
  • Our chemistry teacher often reduces a compound to its components in lab. 在实验室中化学老师常把化合物分解为各种成分。
6 notches be2894ea0263799fb95b9d050d295b3d     
n.(边缘或表面上的)V型痕迹( notch的名词复数 );刻痕;水平;等级
参考例句:
  • The Indians cut notches on a stick to keep count of numbers. 印第安人在棒上刻V形凹痕用来计数。 来自《现代英汉综合大词典》
  • They cut notches in the handle of their pistol for each man they shot. 他们每杀一个人就在枪托上刻下一个V形记号。 来自辞典例句
7 input X6lxm     
n.输入(物);投入;vt.把(数据等)输入计算机
参考例句:
  • I will forever be grateful for his considerable input.我将永远感激他的大量投入。
  • All this information had to be input onto the computer.所有这些信息都必须输入计算机。
8 configuration nYpyb     
n.结构,布局,形态,(计算机)配置
参考例句:
  • Geographers study the configuration of the mountains.地理学家研究山脉的地形轮廓。
  • Prices range from $119 to $199,depending on the particular configuration.价格因具体配置而异,从119美元至199美元不等。
9 silicon dykwJ     
n.硅(旧名矽)
参考例句:
  • This company pioneered the use of silicon chip.这家公司开创了使用硅片的方法。
  • A chip is a piece of silicon about the size of a postage stamp.芯片就是一枚邮票大小的硅片。
TAG标签: material radiation lens
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