The Virginia Tech team put a laser sensor on the front of the car to look for activity in nearby areas.

VOA: special.2009.11.03

And then since we have my red laser pointer, we will also try with the red laser pointer, which is centered at wavelength of 700 nanometers.

然后因为我们有我的红色激光笔，我们也可以用它试一下，它的波长集中在700纳米处。

麻省理工公开课 - 化学原理课程节选

So this gives you a little bit of an idea of just how many individual photons there are in a laser beam of light. This is a huge number of photons.

这个给你们一点思路关于,一个激光束有多少独立的光子,这是一个巨大的光子数目。

麻省理工公开课 - 化学原理课程节选

Before the laser, scientists developed a similar device: a maser which stands for Microwave Amplification by Stimulated Emission of Radiation.

VOA: special.2010.09.01

This angelic laser begins slowly the gradual process in some kind of extraordinary science-fiction sort of way of transforming the virginal human body to the essence of the soul itself.

这天国的激光开始了这渐渐的过程,用一种很特别的科幻小说的方式,把人纯净的身体变成灵魂的精髓。

耶鲁公开课 - 弥尔顿课程节选

Scientific American magazine says huge lasers turn only about twenty to thirty percent of the energy they use into a laser beam.

VOA: special.2010.09.01

They are made of organic matter:the same rules, the same laws of chemistry that apply to what makes this laser glow green apply to what makes these photodetectors work.

而是由有机物制作的，同样的规律，它与应用于让激光的光芒变绿,以及使这些光电探测器工作,的化学是一样的规律。

麻省理工公开课 - 固态化学导论课程节选

A special needle is inserted directly into the tumor and light energy is passed through a laser.

VOA: special.2010.11.23

And actually, could one of the TFs grab the laser point?

事实上，其中一个TFs能不能找到那个激光笔？

哈佛公开课 - 计算机科学课程节选

Doctors Charles Campbell and Charles Koester used a laser to remove a tumor from a patient's eye at Columbia-Presbyterian Hospital in New York City.

VOA: special.2010.09.01

So what we end up with for the number of photons in this laser beam of light is 2.1 times 10 to the 17 photons.

这个激光束的数目是,2，1乘以10的17次方。

麻省理工公开课 - 化学原理课程节选

They include nets,giant collecting arms and powerful laser beams that would move or destroy space junk.

VOA: special.2009.04.01

Intensity, if we increase the intensity, we're not increasing the energy in each photon, we're just increasing the number of photons that we're shooting out of our laser, whatever our light source is.

强度，如果我们增加强度，我们增加的不是,每个光子的能量，我们增加的仅仅是,从我们激光源射出的光子数，无论我们的光源是什么。

麻省理工公开课 - 化学原理课程节选

Laser disc players use lasers to accurately read or write marks on a reflective,coated plastic disc.

VOA: special.2010.09.01

But luckily we had the control of the red laser pointer where nothing moved at all.

但是很幸运我们可以,控制红色激光笔,虽然什么都没有移动。

麻省理工公开课 - 化学原理课程节选

In Theodore Maiman's first laser, a rod of man-made ruby supplied the electrons.

VOA: special.2010.09.01

So we see that we do not eject electrons in the case of the laser pointer, even if we have this intensity, it is still not related to the energy of an individual photon, so we won't see an effect.

所以我们看到我们用激光笔,还是没有逐出电子，即使我们有这样的强度，它仍然与一个单个的光子能量无关,所以我们不会看到光电效应。

麻省理工公开课 - 化学原理课程节选

Mappers and builders use laser technology every day.

VOA: special.2010.09.01

It's as if this celestial laser beam were designed so as to actually shift the atomic structure of the pure corporeal frame of the virgin's body until that body is so rarefied, so pure and ethereal, that it's nothing but soul.

这束天国的激光好像被设计成,去把处女纯净肉体的原子结构,变的纯化，纯粹和飘渺，那就是灵魂。

耶鲁公开课 - 弥尔顿课程节选

Their guns are equipped with a special device that emits laser beams each time a Marine pulls a trigger.

VOA: standard.2010.04.06

Also, what's the energy per photon of this red laser pointer, and then it's also worth trying a calculation dealing with intensity. So let's also try calculating the numbers of photons that would be emitted by this laser pointer, if, for example, we were to use it for 60 seconds and this were a one milliwatt laser.

同样，红色激光笔的,每个光子能量是多少，这也值得用处理强度的方法计算一下,让我们也计算一下,有多少光子会从这个激光笔射出，举个例子，如果我们使用它持续60秒,这里会有一毫瓦的激光。

麻省理工公开课 - 化学原理课程节选

The vests and helmets they are wearing have special sensors, which detect the direction of laser "rounds."

VOA: standard.2010.04.06

(Speaking) With LASIK,doctors use a laser to permanently change the shape of the cornea to improve vision.

VOA: standard.2010.03.03

An Australian company, Electro Optic Systems, has received a $3.5 million government grant to develop the world's first automated, high-precision, laser tracking technology.

VOA: standard.2010.07.24

Its ultimate aim is to build a series of laser tracking stations in various countries to provide a defensive shield for activity in space.

VOA: standard.2010.07.24

When a Marine gets hit by a laser beam, his weapon gets de-activated.

VOA: standard.2010.04.06

Lang lives in the San Francisco bay area. He is a laser physicist and graduate of the California Institute of Technology, and has nearly 50 U.S.patents to his name.

VOA: standard.2010.03.17

Dr.Craig Smith,the chief executive of Electro Optic Systems, says laser beams fired from the ground could protect astronauts and satellites by targeting space junk that travels at potentially devastating speeds.

VOA: standard.2010.07.24

The laser tracking system would work by giving space craft and satellites, which are able to be maneuvered, time to move out of the way of an incoming chunk of debris.

VOA: standard.2010.07.24

Because of their unique surface, each medal is struck with 12 dies nine times with 1,900 tons of pressure, the weight of more than The native designs were laser-engraved on each medal.

VOA: standard.2010.02.16