VOA慢速英语2015 能每秒拍摄数十亿张照片的相机_

 

New Camera Takes Billions of Pictures Every Second 能每秒拍摄数十亿张照片的相机_

Imagine a camera that can take one hundred billion pictures a second -- that is enough to record the fastest movements in the universe.

But we do not have to imagine it, because a scientist has invented such a camera. He calls it an imaging system. It may seem like science fiction, but it is science reality. 

Lihong Wang is a biomedical engineer at Washington University in St. Louis, Missouri. He leads a team of researchers who have discovered several new imaging techniques.

“For the first time, humans can literally¹ see light pulses traveling in space at the speed of light.”

The speed of light is almost 300 million meters per second. At that speed, it would take just one second to travel around the world seven-and-a-half times. Mr. Wang photographs light particles moving at that speed using a unique camera.

“The streak² camera is a very specialized³ device that allows us to convert time into space. We convert light particles, or photons, into electrons, then pull the electrons, really hard, at different rates, depending on the time of arrival. So the time of arrival will be converted into different vertical⁴ positions.”

Mr. Wang’s new technology improves on other ultra-fast cameras in important ways. Until now, streak cameras could only take a one-dimensional photograph. That is like looking through a vertical opening and trying to take a picture of something flying by really fast.

The fastest cameras had to have an external, or outside, light source to work. But Mr. Wang’s technique does not need special lighting⁵. It produces two-dimensional images like regular photographs, but at a speed of one image every 10 trillionths of a second.

Brian Pogue is a biomedical engineer at Dartmouth College in the eastern American state of New Hampshire. He reviewed the new imaging system for the science publication Nature. He says this new way of seeing the movement of light could lead to major scientific discoveries in areas like optical cloaking.

“Cloaking” is a kind of technology that can make an object -- like a spaceship -- seem to disappear. Mr. Pogue says the military would like to use cloaking.

“There’s a lot of interest in getting light to bend around objects, so it sort of looks like you’re seeing through them.”

Brian Pogue says Mr. Wang’s new system lets researchers photograph light as it bends. He says they have not been able to do that until now. He says this development could help make optical cloaking a reality.

Lihong Wang imagines other uses for the new camera in such scientific fields as molecular⁶ biology and astronomy. He says ultrafast imaging could lead to new discoveries.

Words in this Story

astronomy – n. the scientific study of stars, planets, and other objects in outer space

optical – adj. relating to or using light

cloak – v. to hide or disguise something

molecule⁷ – n. the smallest possible amount of a particular substance that has all the characteristics of that substance

technique – n. a way of doing something by using special knowledge or skill

1 literally   

adv.照字面意义，逐字地；确实

参考例句：

• He translated the passage literally.他逐字逐句地翻译这段文字。
• Sometimes she would not sit down till she was literally faint.有时候，她不走到真正要昏厥了，决不肯坐下来。

2 streak   

n.条理，斑纹，倾向，少许，痕迹；v.加条纹，变成条纹，奔驰，快速移动

参考例句：

• The Indians used to streak their faces with paint.印第安人过去常用颜料在脸上涂条纹。
• Why did you streak the tree?你为什么在树上刻条纹？

3 specialized   

adj.专门的，专业化的

参考例句：

• There are many specialized agencies in the United Nations.联合国有许多专门机构。
• These tools are very specialized.这些是专用工具。

4 vertical   

adj.垂直的，顶点的，纵向的；n.垂直物，垂直的位置

参考例句：

• The northern side of the mountain is almost vertical.这座山的北坡几乎是垂直的。
• Vertical air motions are not measured by this system.垂直气流的运动不用这种系统来测量。

5 lighting   

n.照明，光线的明暗，舞台灯光

参考例句：

• The gas lamp gradually lost ground to electric lighting.煤气灯逐渐为电灯所代替。
• The lighting in that restaurant is soft and romantic.那个餐馆照明柔和而且浪漫。

6 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

7 molecule   

n.分子，克分子

参考例句：

• A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
• This gives us the structural formula of the molecule.这种方式给出了分子的结构式。