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  • Translator: Joseph Geni Reviewer: Thu-Huong Ha

    Edgerton博士用這張子彈擊穿蘋果的照片

  • Doc Edgerton inspired us with awe and curiosity

    激起了我們的敬佩和好奇,

  • with this photo of a bullet piercing through an apple,

    這張照片的曝光時間只有一百萬分之一秒。

  • and exposure just a millionth of a second.

    但現在,五十年後,我們可以在快一百萬倍,

  • But now, 50 years later, we can go a million times faster

    也就是不僅在一百萬分之一秒,

  • and see the world not at a million or a billion,

    或者十億分之一秒,

  • but one trillion frames per second.

    而是在萬億分之一秒見捕捉到世界。

  • I present to you a new type of photography,

    現在我給你展示一種新型照相技術,

  • femto-photography,

    叫做飛秒成像,

  • a new imaging technique so fast

    這是一種技術太快以至於

  • that it can create slow motion videos of light in motion.

    它能捕捉到光的運動。

  • And with that, we can create cameras that can look around corners,

    所以用這個技術,我們可以制造

  • beyond line of sight,

    能看到光路拐角的照相機,

  • or see inside our body without an x-ray,

    能看到視野之外

  • and really challenge what we mean by a camera.

    或者不用X光就能透視我們身體的照相機,

  • Now if I take a laser pointer and turn it on and off

    這種相機挑戰了我們對於照相機的定義。

  • in one trillionth of a second --

    現在,如果我用一個激光筆,

  • which is several femtoseconds --

    並且在萬億分之一秒內開關一次——

  • I'll create a packet of photons barely a millimeter wide.

    也就是幾飛秒——

  • And that packet of photons, that bullet,

    我就會制造一些光子,

  • will travel at the speed of light,

    這些光子僅僅是幾毫米寬,

  • and again, a million times faster than an ordinary bullet.

    並且這些光子,像子彈一樣,

  • Now, if you take that bullet and take this packet of photons

    會以光速前進,

  • and fire into this bottle,

    也就是比子彈速度高一百萬倍。

  • how will those photons shatter into this bottle?

    現在,如果你把這個子彈,這些光子

  • How does light look in slow motion?

    打入這個瓶子裏,

  • [Light in Slow Motion ... 10 Billion x Slow]

    這些光子會怎麽樣撞擊瓶子?

  • Now, the whole event --

    光在慢動作下會是什麽樣?

  • (Applause)

    現在,著整個事情—— (鼓掌)

  • Now remember, the whole event is effectively taking place

    (鼓掌)

  • in less than a nanosecond --

    現在,請記住,這整個事情

  • that's how much time it takes for light to travel.

    其實是在一納秒內發生的

  • But I'm slowing down in this video by a factor of 10 billion,

    ——也就是光走的時間——

  • so you can see the light in motion.

    但現在我再把這個錄像放慢一百萬倍

  • (Laughter)

    讓你看到運動中的光。

  • But Coca-Cola did not sponsor this research.

    但可口可樂可沒有資助這個實驗。 (笑聲)

  • (Laughter)

    現在,在這裏有很多事會發生,

  • Now, there's a lot going on in this movie,

    所以讓我一件一件的展示。

  • so let me break this down and show you what's going on.

    現在,光束進入瓶子,也就是我們的子彈,

  • So the pulse enters the bottle, our bullet,

    穿過瓶子,

  • with a packet of photons that start traveling through

    並且在內部散射開來。

  • and that start scattering inside.

    一些光流了出來,到了桌子上,

  • Some of the light leaks, goes on the table,

    所以你開始看到這些波紋。

  • and you start seeing these ripples of waves.

    許多光子最終到達了瓶蓋處

  • Many of the photons eventually reach the cap

    並且向四周散去。

  • and then they explode in various directions.

    你能看到,這裏是一個空氣泡,

  • As you can see, there's a bubble of air

    它在裏面反彈。

  • and it's bouncing around inside.

    同時,波紋也到了桌子上,

  • Meanwhile, the ripples are traveling on the table,

    並且因爲在頂部的反射,

  • and because of the reflections at the top,

    你能看到在瓶子底部,幾幀之後,

  • you see at the back of the bottle, after several frames,

    反射彙聚了。

  • the reflections are focused.

    現在,如果你用普通的子彈

  • Now, if you take an ordinary bullet

    走同樣的路程,平且放慢視頻,

  • and let it go the same distance and slow down the video --

    同樣是一百萬倍,你知道

  • again, by a factor of 10 billion --

    你需要等多久來看到這個全過程嗎?

  • do you know how long you'll have to sit here to watch that movie?

    一天,一周?實際上,是一年。

  • (Laughter)

    這當然會很無聊 (笑聲)

  • A day, a week? Actually, a whole year.

    一個慢的,普通的子彈運動錄像。

  • It'll be a very boring movie --

    但一些靜物照相又如何呢?

  • (Laughter)

    你可以看到波紋再次在桌子上展開,

  • of a slow, ordinary bullet in motion.

    背景是紅番茄和牆。

  • And what about some still-life photography?

    這就像在水池裏扔一塊石頭。

  • You can watch the ripples, again, washing over the table,

    我想,這就是自然如何繪制的紅番茄,

  • the tomato and the wall in the back.

    一飛秒一飛秒,

  • It's like throwing a stone in a pond of water.

    但當然我們眼睛看到的是整體的結合。

  • I thought: this is how nature paints a photo,

    但如果你在看一下這個紅番茄,

  • one femto frame at a time,

    你就會注意到,當光在紅番茄上走過時,

  • but of course our eye sees an integral composite.

    它一直在閃耀。它並沒有變暗。

  • But if you look at this tomato one more time,

    爲什麽?因爲紅番茄熟了,

  • you will notice, as the light washes over the tomato,

    並且光在紅番茄內部反射,

  • it continues to glow.

    在幾萬億分之一秒後出來。

  • It doesn't become dark. Why is that?

    所以,在未來,當飛米成像相機

  • Because the tomato is actually ripe,

    在你的手機裏的時候,

  • and the light is bouncing around inside the tomato,

    你就可以去超市,

  • and it comes out after several trillionths of a second.

    不用摸就能檢查一下水果是否熟了。

  • So in the future, when this femto-camera is in your camera phone,

    那麽,麻省理工學院的團隊是怎麽做出這個相機的呢?

  • you might be able to go to a supermarket

    現在,作爲攝影師,你知道,

  • and check if the fruit is ripe without actually touching it.

    如果你想要短時曝光,你只有一點點光,

  • (Laughter)

    但我們需要比最短的曝光時間

  • So how did my team at MIT create this camera?

    快一百萬倍,

  • Now, as photographers, you know,

    所以你幾乎得不到任何光。

  • if you take a short exposure photo, you get very little light.

    所以,我們做的是,

  • But we're going to go a billion times faster than your shortest exposure,

    把這些光子送進去,並重複百萬多次,

  • so you're going to get hardly any light.

    每次都以極好的同步錄像,

  • So what we do is we send that bullet --

    然後從數十億位元的數據中,

  • that packet of photons -- millions of times,

    我們“編織”起來一幅圖,

  • and record again and again with very clever synchronization,

    而這幅圖就是你們之前看到的。

  • and from the gigabytes of data,

    並且我們把所有的原始數據到算進去時,

  • we computationally weave together

    進行很有趣的處理。

  • to create those femto-videos I showed you.

    現在,超人能飛。

  • And we can take all that raw data and treat it in very interesting ways.

    一些其他英雄能隱身,

  • So, Superman can fly.

    但想象一個未來的超人:

  • Some other heroes can become invisible.

    他能看到拐角後面的東西。

  • But what about a new power for a future superhero:

    這原理是我們可以把一些光打到門上,

  • To see around corners.

    這些光會反射進入房間,

  • The idea is that we could shine some light on the door,

    一些會返回到門上,

  • it's going to bounce, go inside the room,

    然後進入照相機,

  • some of that is going to reflect back on the door,

    這樣我們就可以利用這些光的反射。

  • and then back to the camera.

    這可不是科幻片。我們真正的做出來了。

  • And we could exploit these multiple bounces of light.

    在左邊,你看到了我們的飛秒成像相機。

  • And it's not science fiction. We have actually built it.

    在牆後面有一個人體模型,

  • On the left, you see our femto-camera.

    我們將進行光反射。

  • There's a mannequin hidden behind a wall,

    所以,在我們的論文發表

  • and we're going to bounce light off the door.

    在《自然》上後,

  • So after our paper was published in Nature Communications,

    它被推薦到自然的官網上,

  • it was highlighted by Nature.com,

    然後他們創造了這個動畫。

  • and they created this animation.

    (音樂)

  • (Music)

    我們將要發射這些光子彈,

  • [A laser pulse is fired]

    它們將要撞擊這個牆,

  • (Music)

    並且因爲這束光

  • Ramesh Raskar: We're going to fire those bullets of light,

    會散射到各個方向,

  • and they're going to hit this wall,

    一些會最終打到我們的隱藏的假人上,

  • and because of the packet of the photons,

    並且會繼續散射,

  • they will scatter in all the directions,

    知道這個門也會反射

  • and some of them will reach our hidden mannequin,

    一些光,

  • which in turn will again scatter that light,

    而一部分光會最終

  • and again in turn, the door will reflect some of that scattered light.

    返回到相機裏,但最有趣的是,

  • And a tiny fraction of the photons will actually come back to the camera,

    它們會在略微不同的時間到達。

  • but most interestingly,

    (音樂)

  • they will all arrive at a slightly different time slot.

    而且因爲我們有一個可以運行如此之快的相機,

  • (Music)

    也就是我們的飛秒相機,這個相機就有一些特別的能力。

  • And because we have a camera that can run so fast --

    它有很好的時間分辨率,

  • our femto-camera -- it has some unique abilities.

    並且可以以光速捕捉世界。

  • It has very good time resolution,

    所以這樣,我們不僅知道相機到門的距離,

  • and it can look at the world at the speed of light.

    同時知道到隱藏物品的距離,

  • And this way, we know the distances, of course to the door,

    但我們不知道哪個點

  • but also to the hidden objects,

    對應哪個距離。

  • but we don't know which point corresponds to which distance.

    (音樂)

  • (Music)

    通過用激光,我們能記錄一個原始的照片,

  • By shining one laser, we can record one raw photo,

    也就是你們在屏幕上看到的這個,好像沒什麽意義,

  • which, if you look on the screen, doesn't really make any sense.

    但然後我們會拍很多照片,

  • But then we will take a lot of such pictures,

    很多很多,放到一起,

  • dozens of such pictures, put them together,

    然後分析光的反射,

  • and try to analyze the multiple bounces of light,

    現在我們能看到那個隱藏的物體了嗎?

  • and from that, can we see the hidden object?

    我們能立體的看懂嗎?

  • Can we see it in full 3D?

    這就是我們的模型重建。 (音樂)

  • So this is our reconstruction.

    (音樂)

  • (Music)

    (音樂) (掌聲)

  • (Applause)

    現在距離我們在將這科技應用到生活中

  • Now, we have some ways to go

    還有一些路要走,

  • before we take this outside the lab on the road,

    但在未來,我們可以把這個技術放到車裏,

  • but in the future, we could create cars that avoid collisions

    這樣車就能防止碰撞,因爲他們能看到拐角,

  • with what's around the bend.

    或者我們可以搜尋幸存者,

  • Or we can look for survivors in hazardous conditions

    因爲我們能看到在窗戶上反射的光,

  • by looking at light reflected through open windows.

    或者我們可以建造透視儀,

  • Or we can build endoscopes that can see deep inside the body around occluders,

    來看到身體裏的情況,

  • and also for cardioscopes.

    我們甚至可以透視心臟。

  • But of course, because of tissue and blood,

    但當然,由於各種組織和血液的幹擾,

  • this is quite challenging,

    這回相當困難,

  • so this is really a call for scientists

    所以我們呼籲科學家來真正重視飛秒成像,

  • to start thinking about femto-photography

    把這個技術作爲一種

  • as really a new imaging modality

    解決下一代健康問題的新模型。

  • to solve the next generation of health-imaging problems.

    現在,就像Edgerton博士,一個科學家,

  • Now, like Doc Edgerton, a scientist himself,

    科學變成了藝術,一種高速攝影藝術,

  • science became art --

    而且我意識到我們每次

  • an art of ultra-fast photography.

    大量資料

  • And I realized

    不僅是科學成像,

  • that all the gigabytes of data that we're collecting every time,

    而是一種新的計算性攝影,

  • are not just for scientific imaging.

    這種技術蘊含了時間延遲和彩色編碼,

  • But we can also do a new form of computational photography,

    我們看這些波紋。

  • with time-lapse and color coding.

    記住,這些波紋之間的時間

  • And we look at those ripples.

    僅僅是幾個萬億分之一秒。

  • Remember:

    但有些有趣的事正在發生,

  • The time between each of those ripples is only a few trillionths of a second.

    當你看到這些蓋子下的波紋時,

  • But there's also something funny going on here.

    他們正在離我們遠去。

  • When you look at the ripples under the cap,

    但這些波紋應該向我們移動。

  • the ripples are moving away from us.

    發生了什麽?

  • The ripples should be moving towards us.

    結果是,因爲我們在以接近光速

  • What's going on here?

    來錄這些東西,

  • It turns out, because we're recording nearly at the speed of light,

    我們有一些奇怪的現象,

  • we have strange effects,

    愛因斯坦會相當高興看到這些圖片。

  • and Einstein would have loved to see this picture.

    事件發生的順序

  • (Laughter)

    在相機裏有時候被反轉了,

  • The order at which events take place in the world

    所以通過對應時間和空間的扭曲,

  • appears in the camera sometimes in reversed order.

    我們可以修正這個扭曲。

  • So by applying the corresponding space and time warp,

    所以不管是看到拐角,

  • we can correct for this distortion.

    還是爲下一代製造健康影像,

  • So whether it's for photography around corners,

    還是增加新的可視化,

  • or creating the next generation of health imaging,

    自從我們的發明,

  • or creating new visualizations,

    我們就已經把所有的資料和細節放到了我們的網上,

  • since our invention,

    並且我們希望,這個DIY,這個創意的研究團體,

  • we have open-sourced all the data and details on our website,

    可以告訴我們

  • and our hope is that the DIY, the creative and the research communities

    我們不應該再迷上高像素 —(笑聲)—

  • will show us that we should stop obsessing about the megapixels in cameras --

    而開始關注成像技術的另一個維度。

  • (Laughter)

    時間差不多了。謝謝。 (掌聲)

  • and start focusing on the next dimension in imaging.

    (掌聲)

  • It's about time.

  • Thank you.

  • (Applause)

Translator: Joseph Geni Reviewer: Thu-Huong Ha

Edgerton博士用這張子彈擊穿蘋果的照片

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B1 中級 中文 TED 相機 光子 看到 子彈 番茄

【TED】Ramesh Raskar:每秒一萬億幀的成像 (Imaging at a trillion frames per second | Ramesh Raskar) (【TED】Ramesh Raskar: Imaging at a trillion frames per second (Imaging at a trillion frames per second | Ramesh Raskar))

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