激光是如何工作的（实践篇） - 每天聪明一点点 33：英语精读讲义

Hey, it's me Destin.

嘿，我是 Destin。

Welcome to Smarter Every Day.

欢迎收看 Smarter Every Day。

So, I'm in the Netherlands today and I'm hanging out with a buddy of mine that I met through a research project. 講解

今天我在荷兰，和我通过一个研究项目认识的哥们儿待在一起。

His name is Johan

他的名字叫 Johan

Kr... Reinink.

Kr... Reinink。

That. So anyway,

就是他。总之，

Johan is a laser expert and I've worked with him on stuff on the internet.

Johan 是一位激光专家，我在网上和他合作过一些项目。

So, we're going to show you how lasers work today. 語法

所以，我们今天打算给你们展示激光是如何工作的。

So, uh this is an open cavity laser and can you explain the main components of an open cavity laser? 用詞

那么，呃，这是一个开腔激光器，你能解释一下开腔激光器的主要部件吗？

Here we have the laser tube of the helium neon gas fill that amplifies the light

这里我们有充入氦氖气体的激光管，用来放大光，

and we have at both ends uh mirrors that are aligned to bounce the light back and forth. 短語搭配

我们在两端，呃，有对齐的反射镜，能让光来回反射。

Should we power it up? 短語動詞

我们该通电了吗？

Definitely.

当然。

There’s a 4-second delay.

有4秒钟的延迟。

It's a safety feature.

这是一个安全功能。

All right.

好的。

Sweet.

酷。

The helium neon laser tube is uh just a glorified the neon light.

氦氖激光管呃，只是一种高级一点的霓虹灯。

Just uh you have the electrical discharge is going through it like a neon sign 用詞

只是呃，有放电穿过它，就像霓虹灯招牌一样，

and the special thing is you have here uh two apertures and the light can bounce straight through. 表達脈絡

特别之处在于这里有，呃，两个孔径，光可以笔直地穿过去。

Okay, so at both sides of the laser tube we have placed two high-reflecting mirrors

好的，所以在激光管的两侧，我们放置了两个高反射镜，

and the light that goes through the laser tube hits the mirror and bounces back and forth through the tube

穿过激光管的光击中镜子，在管子里来回反射，

and each time it passes the tube it gets amplified. 語法

每穿过一次管子，它就会被放大一次。

If you make this mirror slightly transparent, it's 2% transparent, 語法

如果你让这面镜子稍微透明一点，有2%的透明度，

and each time the light passes 2% moves out and you have like a beam going on here.

那么每次光通过时，就会有2%射出，这样你就会得到一束光束。

Yeah.

对。

Okay, so basically what comes out the other end of the mirror is the imperfection in the mirror. 語法

好的，所以基本上从镜子另一端出来的，是镜子的不完美之处。

If it was a perfect mirror, we wouldn't get any output from the laser, correct? 語法

如果它是一面完美的镜子，我们就得不到激光器的任何输出，对吧？

Correct.

对。

But because the mirrors are imperfect, we do get a little lasing. 講解

但因为镜子是不完美的，我们确实得到了一点激光。

Yeah.

是的。

In this case, the laser is just specifically made to reflect only 98% and this is the 2% of the light uh that comes out.

在这种情况下，激光器经过特殊制造，只能反射98%，出来的呃这部分就是2%的光。

All right, one thing I notice is that inside the cavity, the beam is much stronger. 表達脈絡

好的，我注意到一件事，就是在腔内，光束要强得多。

You can see the laser hitting particles in the air, 語法

你可以看到激光击中空气中的颗粒，

but downstream the photons that are leaking out of the mirror, 講解

但在下游，从镜子漏出的光子，

it's not quite as strong. 語法

却没有那么强。

Is that correct?

是这样吗？

Yeah.

是的。

The light circulating inside the laser uh is uh far higher intensity.

在激光器内部循环的光，呃，强度要高得多。

And if you hold your hand outside of the laser and block the beam,

如果你把手放在激光器外面挡住光束，

you see that you catch the beam.

你会看到你接住了光束。

It looks pretty nice.

看起来很漂亮。

But if you hold your hand inside the cavity, you'll block the laser from uh amplifying all the light 語法

但如果你把手放在腔内，你就会阻止激光，呃，放大所有的光，

and the light won't circulate around and you don't uh have a laser anymore.

光就不会循环了，你也就不再，呃，拥有激光了。

So, it stops way on the other side 用詞

所以，它在另一边停了下来，

even though we're stopping it on this side of the tube, we don't get lasing on the other side. 語法

尽管我们在管子的这一边挡住了它，我们在另一边也没有得到激光。

I'm waiting on photon torpedo technology myself, 講解

我自己正在等待光子鱼雷技术，

so I'm working on it.

所以我正在研究它。

You're working on it?

你在研究它？

Excellent.

太棒了。

But anyway, we want to thank Johan for his time 短語搭配

但无论如何，我们要感谢 Johan 抽出的时间，

and uh can you thank the people who let us in in Dutch? 短語動詞

还有呃，你能用荷兰语感谢一下让我们进来的人吗？

Absolutely.

当然可以。

Yeah, I thank the optical science group that we could be in the lab and we could film.

是的，我感谢光学科学小组让我们进入实验室进行拍摄。

Thank you very much

非常感谢，

and thank you for your explanation that we could be in the lab and could see what you did.

也感谢你的讲解，让我们能在实验室里看到你所做的。

Also, thank you very much and thank you for this laser we could borrow and transport.

还有，非常感谢你们借给我们并运送这台激光器。

Thank you very much.

非常感谢。

Without all these people, we couldn't have done it. 語法

没有这些人，我们无法完成这件事。

Yeah, for everyone, if you come to the university, come here and look at it.

对，对于所有人来说，如果你来到大学，来看看这个吧。

Go study.

去学习吧。

What? Did you just call me something?

什么？你刚才是在说我吗？

No.

不是。

Do you want to get even smarter?

你想变得更聪明吗？

Then check out this video by MinutePhysics.

看看 MinutePhysics 的这个视频吧。

Henry explains what's going on inside that helium-neon tube in one of his cool science videos. 短語動詞

Henry 在他那些很酷的科学视频的其中一个里，解释了氦氖管里发生了什么。

Now we are going to do Laser Month.

现在我们要进行“激光月”活动。

Laser Month consists of a lot of videos shot over here in Holland with Johan 短語搭配

“激光月”包含很多在这里（荷兰）和 Johan 一起拍摄的视频，

because he is a laser genius.

因为他是个激光天才。

Can I call you a laser genius?

我可以叫你激光天才吗？

Definitely.

当然。

All right, so now we're going to play laser limbo. 文化背景

好了，现在我们来玩激光凌波舞（Laser limbo）。

Ready?

准备好了吗？

No.

没有。

Why not?

为什么不？

It's dangerous.

很危险。

Oh, c'mon, laser limbo. 語氣意圖

拜托，激光凌波舞哎。