[Script Info] Title: [Events] Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text Dialogue: 0,0:00:00.90,0:00:06.86,Default,,0000,0000,0000,,Doc Edgerton inspired us\Nwith awe and curiosity Dialogue: 0,0:00:06.88,0:00:12.12,Default,,0000,0000,0000,,with this photo of a bullet\Npiercing through an apple, Dialogue: 0,0:00:12.14,0:00:15.99,Default,,0000,0000,0000,,and exposure just a millionth of a second. Dialogue: 0,0:00:17.66,0:00:24.55,Default,,0000,0000,0000,,But now, 50 years later,\Nwe can go a million times faster Dialogue: 0,0:00:24.57,0:00:29.34,Default,,0000,0000,0000,,and see the world\Nnot at a million or a billion, Dialogue: 0,0:00:29.36,0:00:32.41,Default,,0000,0000,0000,,but one trillion frames per second. Dialogue: 0,0:00:33.86,0:00:37.53,Default,,0000,0000,0000,,I present to you\Na new type of photography, Dialogue: 0,0:00:37.55,0:00:39.59,Default,,0000,0000,0000,,femto-photography, Dialogue: 0,0:00:39.61,0:00:44.19,Default,,0000,0000,0000,,a new imaging technique so fast Dialogue: 0,0:00:44.21,0:00:48.48,Default,,0000,0000,0000,,that it can create slow motion\Nvideos of light in motion. Dialogue: 0,0:00:49.41,0:00:54.27,Default,,0000,0000,0000,,And with that, we can create cameras\Nthat can look around corners, Dialogue: 0,0:00:54.30,0:00:56.27,Default,,0000,0000,0000,,beyond line of sight, Dialogue: 0,0:00:56.29,0:01:01.15,Default,,0000,0000,0000,,or see inside our body without an x-ray, Dialogue: 0,0:01:01.17,0:01:04.98,Default,,0000,0000,0000,,and really challenge\Nwhat we mean by a camera. Dialogue: 0,0:01:06.44,0:01:09.57,Default,,0000,0000,0000,,Now if I take a laser pointer\Nand turn it on and off Dialogue: 0,0:01:09.60,0:01:12.40,Default,,0000,0000,0000,,in one trillionth of a second -- Dialogue: 0,0:01:12.42,0:01:15.21,Default,,0000,0000,0000,,which is several femtoseconds -- Dialogue: 0,0:01:15.24,0:01:19.23,Default,,0000,0000,0000,,I'll create a packet of photons\Nbarely a millimeter wide. Dialogue: 0,0:01:20.36,0:01:22.77,Default,,0000,0000,0000,,And that packet of photons, that bullet, Dialogue: 0,0:01:22.79,0:01:24.72,Default,,0000,0000,0000,,will travel at the speed of light, Dialogue: 0,0:01:24.74,0:01:28.70,Default,,0000,0000,0000,,and again, a million times faster\Nthan an ordinary bullet. Dialogue: 0,0:01:29.62,0:01:34.13,Default,,0000,0000,0000,,Now, if you take that bullet\Nand take this packet of photons Dialogue: 0,0:01:34.16,0:01:37.49,Default,,0000,0000,0000,,and fire into this bottle, Dialogue: 0,0:01:37.51,0:01:41.08,Default,,0000,0000,0000,,how will those photons\Nshatter into this bottle? Dialogue: 0,0:01:41.86,0:01:44.45,Default,,0000,0000,0000,,How does light look in slow motion? Dialogue: 0,0:01:44.55,0:01:47.55,Default,,0000,0000,0000,,[Light in Slow Motion ...\N10 Billion x Slow] Dialogue: 0,0:02:06.04,0:02:07.59,Default,,0000,0000,0000,,Now, the whole event -- Dialogue: 0,0:02:07.61,0:02:14.60,Default,,0000,0000,0000,,(Applause) Dialogue: 0,0:02:14.62,0:02:18.12,Default,,0000,0000,0000,,Now remember, the whole event\Nis effectively taking place Dialogue: 0,0:02:18.15,0:02:19.81,Default,,0000,0000,0000,,in less than a nanosecond -- Dialogue: 0,0:02:19.84,0:02:22.24,Default,,0000,0000,0000,,that's how much time\Nit takes for light to travel. Dialogue: 0,0:02:22.26,0:02:26.91,Default,,0000,0000,0000,,But I'm slowing down in this video\Nby a factor of 10 billion, Dialogue: 0,0:02:26.93,0:02:29.48,Default,,0000,0000,0000,,so you can see the light in motion. Dialogue: 0,0:02:29.50,0:02:30.57,Default,,0000,0000,0000,,(Laughter) Dialogue: 0,0:02:30.60,0:02:32.88,Default,,0000,0000,0000,,But Coca-Cola did not\Nsponsor this research. Dialogue: 0,0:02:32.91,0:02:35.01,Default,,0000,0000,0000,,(Laughter) Dialogue: 0,0:02:35.03,0:02:37.06,Default,,0000,0000,0000,,Now, there's a lot going on in this movie, Dialogue: 0,0:02:37.08,0:02:39.70,Default,,0000,0000,0000,,so let me break this down\Nand show you what's going on. Dialogue: 0,0:02:39.72,0:02:42.66,Default,,0000,0000,0000,,So the pulse enters\Nthe bottle, our bullet, Dialogue: 0,0:02:42.68,0:02:45.22,Default,,0000,0000,0000,,with a packet of photons\Nthat start traveling through Dialogue: 0,0:02:45.24,0:02:47.06,Default,,0000,0000,0000,,and that start scattering inside. Dialogue: 0,0:02:47.08,0:02:49.29,Default,,0000,0000,0000,,Some of the light leaks,\Ngoes on the table, Dialogue: 0,0:02:49.31,0:02:51.92,Default,,0000,0000,0000,,and you start seeing\Nthese ripples of waves. Dialogue: 0,0:02:51.95,0:02:54.96,Default,,0000,0000,0000,,Many of the photons\Neventually reach the cap Dialogue: 0,0:02:54.98,0:02:57.87,Default,,0000,0000,0000,,and then they explode\Nin various directions. Dialogue: 0,0:02:57.90,0:02:59.78,Default,,0000,0000,0000,,As you can see, there's a bubble of air Dialogue: 0,0:02:59.81,0:03:01.45,Default,,0000,0000,0000,,and it's bouncing around inside. Dialogue: 0,0:03:01.47,0:03:03.92,Default,,0000,0000,0000,,Meanwhile, the ripples\Nare traveling on the table, Dialogue: 0,0:03:03.95,0:03:05.95,Default,,0000,0000,0000,,and because of the reflections at the top, Dialogue: 0,0:03:05.97,0:03:09.72,Default,,0000,0000,0000,,you see at the back of the bottle,\Nafter several frames, Dialogue: 0,0:03:09.74,0:03:11.44,Default,,0000,0000,0000,,the reflections are focused. Dialogue: 0,0:03:13.21,0:03:18.60,Default,,0000,0000,0000,,Now, if you take an ordinary bullet Dialogue: 0,0:03:18.62,0:03:21.62,Default,,0000,0000,0000,,and let it go the same distance\Nand slow down the video -- Dialogue: 0,0:03:21.65,0:03:23.87,Default,,0000,0000,0000,,again, by a factor of 10 billion -- Dialogue: 0,0:03:23.89,0:03:28.28,Default,,0000,0000,0000,,do you know how long you'll have to sit\Nhere to watch that movie? Dialogue: 0,0:03:28.31,0:03:29.90,Default,,0000,0000,0000,,(Laughter) Dialogue: 0,0:03:29.92,0:03:33.43,Default,,0000,0000,0000,,A day, a week? Actually, a whole year. Dialogue: 0,0:03:34.31,0:03:36.57,Default,,0000,0000,0000,,It'll be a very boring movie -- Dialogue: 0,0:03:36.59,0:03:37.98,Default,,0000,0000,0000,,(Laughter) Dialogue: 0,0:03:38.00,0:03:41.38,Default,,0000,0000,0000,,of a slow, ordinary bullet in motion. Dialogue: 0,0:03:42.70,0:03:46.06,Default,,0000,0000,0000,,And what about some\Nstill-life photography? Dialogue: 0,0:03:53.11,0:03:58.10,Default,,0000,0000,0000,,You can watch the ripples,\Nagain, washing over the table, Dialogue: 0,0:03:58.12,0:04:00.78,Default,,0000,0000,0000,,the tomato and the wall in the back. Dialogue: 0,0:04:00.80,0:04:03.59,Default,,0000,0000,0000,,It's like throwing a stone\Nin a pond of water. Dialogue: 0,0:04:07.40,0:04:11.06,Default,,0000,0000,0000,,I thought: this is how\Nnature paints a photo, Dialogue: 0,0:04:11.09,0:04:13.65,Default,,0000,0000,0000,,one femto frame at a time, Dialogue: 0,0:04:13.67,0:04:17.93,Default,,0000,0000,0000,,but of course our eye sees\Nan integral composite. Dialogue: 0,0:04:19.92,0:04:22.06,Default,,0000,0000,0000,,But if you look at this tomato\None more time, Dialogue: 0,0:04:22.08,0:04:24.83,Default,,0000,0000,0000,,you will notice, as the light\Nwashes over the tomato, Dialogue: 0,0:04:24.85,0:04:26.51,Default,,0000,0000,0000,,it continues to glow. Dialogue: 0,0:04:26.54,0:04:28.56,Default,,0000,0000,0000,,It doesn't become dark. Why is that? Dialogue: 0,0:04:28.59,0:04:30.89,Default,,0000,0000,0000,,Because the tomato is actually ripe, Dialogue: 0,0:04:30.91,0:04:33.30,Default,,0000,0000,0000,,and the light is bouncing\Naround inside the tomato, Dialogue: 0,0:04:33.32,0:04:36.74,Default,,0000,0000,0000,,and it comes out after several\Ntrillionths of a second. Dialogue: 0,0:04:37.71,0:04:42.05,Default,,0000,0000,0000,,So in the future, when this femto-camera\Nis in your camera phone, Dialogue: 0,0:04:42.08,0:04:44.03,Default,,0000,0000,0000,,you might be able to go to a supermarket Dialogue: 0,0:04:44.06,0:04:47.11,Default,,0000,0000,0000,,and check if the fruit is ripe\Nwithout actually touching it. Dialogue: 0,0:04:47.13,0:04:48.82,Default,,0000,0000,0000,,(Laughter) Dialogue: 0,0:04:48.84,0:04:52.53,Default,,0000,0000,0000,,So how did my team at MIT\Ncreate this camera? Dialogue: 0,0:04:53.91,0:04:55.85,Default,,0000,0000,0000,,Now, as photographers, you know, Dialogue: 0,0:04:55.87,0:04:59.84,Default,,0000,0000,0000,,if you take a short exposure photo,\Nyou get very little light. Dialogue: 0,0:04:59.86,0:05:03.37,Default,,0000,0000,0000,,But we're going to go a billion times\Nfaster than your shortest exposure, Dialogue: 0,0:05:03.39,0:05:05.32,Default,,0000,0000,0000,,so you're going to get hardly any light. Dialogue: 0,0:05:05.34,0:05:07.26,Default,,0000,0000,0000,,So what we do is we send that bullet -- Dialogue: 0,0:05:07.28,0:05:09.78,Default,,0000,0000,0000,,that packet of photons --\Nmillions of times, Dialogue: 0,0:05:09.80,0:05:12.88,Default,,0000,0000,0000,,and record again and again\Nwith very clever synchronization, Dialogue: 0,0:05:12.91,0:05:14.85,Default,,0000,0000,0000,,and from the gigabytes of data, Dialogue: 0,0:05:14.87,0:05:17.09,Default,,0000,0000,0000,,we computationally weave together Dialogue: 0,0:05:17.12,0:05:20.01,Default,,0000,0000,0000,,to create those femto-videos I showed you. Dialogue: 0,0:05:21.20,0:05:25.35,Default,,0000,0000,0000,,And we can take all that raw data\Nand treat it in very interesting ways. Dialogue: 0,0:05:26.02,0:05:27.83,Default,,0000,0000,0000,,So, Superman can fly. Dialogue: 0,0:05:27.86,0:05:30.11,Default,,0000,0000,0000,,Some other heroes can become invisible. Dialogue: 0,0:05:30.61,0:05:35.39,Default,,0000,0000,0000,,But what about a new power\Nfor a future superhero: Dialogue: 0,0:05:35.42,0:05:37.28,Default,,0000,0000,0000,,To see around corners. Dialogue: 0,0:05:38.09,0:05:42.56,Default,,0000,0000,0000,,The idea is that we could\Nshine some light on the door, Dialogue: 0,0:05:42.59,0:05:45.24,Default,,0000,0000,0000,,it's going to bounce, go inside the room, Dialogue: 0,0:05:45.26,0:05:47.67,Default,,0000,0000,0000,,some of that is going to reflect\Nback on the door, Dialogue: 0,0:05:47.69,0:05:49.18,Default,,0000,0000,0000,,and then back to the camera. Dialogue: 0,0:05:49.20,0:05:52.20,Default,,0000,0000,0000,,And we could exploit\Nthese multiple bounces of light. Dialogue: 0,0:05:52.69,0:05:55.35,Default,,0000,0000,0000,,And it's not science fiction.\NWe have actually built it. Dialogue: 0,0:05:55.38,0:05:57.44,Default,,0000,0000,0000,,On the left, you see our femto-camera. Dialogue: 0,0:05:57.47,0:05:59.82,Default,,0000,0000,0000,,There's a mannequin hidden behind a wall, Dialogue: 0,0:05:59.85,0:06:02.35,Default,,0000,0000,0000,,and we're going to bounce\Nlight off the door. Dialogue: 0,0:06:02.75,0:06:06.24,Default,,0000,0000,0000,,So after our paper was published\Nin Nature Communications, Dialogue: 0,0:06:06.27,0:06:08.41,Default,,0000,0000,0000,,it was highlighted by Nature.com, Dialogue: 0,0:06:08.43,0:06:10.91,Default,,0000,0000,0000,,and they created this animation. Dialogue: 0,0:06:10.93,0:06:12.22,Default,,0000,0000,0000,,(Music) Dialogue: 0,0:06:12.24,0:06:15.10,Default,,0000,0000,0000,,[A laser pulse is fired] Dialogue: 0,0:06:15.13,0:06:18.00,Default,,0000,0000,0000,,(Music) Dialogue: 0,0:06:18.02,0:06:20.89,Default,,0000,0000,0000,,Ramesh Raskar: We're going to fire\Nthose bullets of light, Dialogue: 0,0:06:20.92,0:06:24.29,Default,,0000,0000,0000,,and they're going to hit this wall, Dialogue: 0,0:06:24.32,0:06:26.95,Default,,0000,0000,0000,,and because of the packet of the photons, Dialogue: 0,0:06:26.97,0:06:29.08,Default,,0000,0000,0000,,they will scatter in all the directions, Dialogue: 0,0:06:29.10,0:06:31.44,Default,,0000,0000,0000,,and some of them will reach\Nour hidden mannequin, Dialogue: 0,0:06:31.47,0:06:34.85,Default,,0000,0000,0000,,which in turn will again\Nscatter that light, Dialogue: 0,0:06:34.88,0:06:39.45,Default,,0000,0000,0000,,and again in turn, the door will reflect\Nsome of that scattered light. Dialogue: 0,0:06:40.68,0:06:44.18,Default,,0000,0000,0000,,And a tiny fraction of the photons\Nwill actually come back to the camera, Dialogue: 0,0:06:44.20,0:06:45.35,Default,,0000,0000,0000,,but most interestingly, Dialogue: 0,0:06:45.38,0:06:48.46,Default,,0000,0000,0000,,they will all arrive\Nat a slightly different time slot. Dialogue: 0,0:06:48.93,0:06:53.76,Default,,0000,0000,0000,,(Music) Dialogue: 0,0:06:53.78,0:06:56.30,Default,,0000,0000,0000,,And because we have a camera\Nthat can run so fast -- Dialogue: 0,0:06:56.32,0:06:59.40,Default,,0000,0000,0000,,our femto-camera --\Nit has some unique abilities. Dialogue: 0,0:06:59.43,0:07:02.24,Default,,0000,0000,0000,,It has very good time resolution, Dialogue: 0,0:07:02.27,0:07:05.16,Default,,0000,0000,0000,,and it can look at the world\Nat the speed of light. Dialogue: 0,0:07:06.11,0:07:09.37,Default,,0000,0000,0000,,And this way, we know the distances,\Nof course to the door, Dialogue: 0,0:07:09.40,0:07:11.17,Default,,0000,0000,0000,,but also to the hidden objects, Dialogue: 0,0:07:11.20,0:07:14.35,Default,,0000,0000,0000,,but we don't know which point\Ncorresponds to which distance. Dialogue: 0,0:07:14.38,0:07:18.42,Default,,0000,0000,0000,,(Music) Dialogue: 0,0:07:18.45,0:07:21.88,Default,,0000,0000,0000,,By shining one laser,\Nwe can record one raw photo, Dialogue: 0,0:07:21.90,0:07:24.92,Default,,0000,0000,0000,,which, if you look on the screen,\Ndoesn't really make any sense. Dialogue: 0,0:07:24.95,0:07:27.07,Default,,0000,0000,0000,,But then we will take\Na lot of such pictures, Dialogue: 0,0:07:27.09,0:07:29.25,Default,,0000,0000,0000,,dozens of such pictures,\Nput them together, Dialogue: 0,0:07:29.28,0:07:31.73,Default,,0000,0000,0000,,and try to analyze\Nthe multiple bounces of light, Dialogue: 0,0:07:31.76,0:07:35.21,Default,,0000,0000,0000,,and from that, can we see\Nthe hidden object? Dialogue: 0,0:07:35.23,0:07:37.37,Default,,0000,0000,0000,,Can we see it in full 3D? Dialogue: 0,0:07:38.11,0:07:40.04,Default,,0000,0000,0000,,So this is our reconstruction. Dialogue: 0,0:07:40.07,0:07:45.20,Default,,0000,0000,0000,,(Music) Dialogue: 0,0:07:45.22,0:07:52.20,Default,,0000,0000,0000,,(Applause) Dialogue: 0,0:07:52.79,0:07:54.26,Default,,0000,0000,0000,,Now, we have some ways to go Dialogue: 0,0:07:54.28,0:07:57.42,Default,,0000,0000,0000,,before we take this\Noutside the lab on the road, Dialogue: 0,0:07:57.44,0:08:01.17,Default,,0000,0000,0000,,but in the future, we could create\Ncars that avoid collisions Dialogue: 0,0:08:01.20,0:08:02.68,Default,,0000,0000,0000,,with what's around the bend. Dialogue: 0,0:08:03.58,0:08:07.67,Default,,0000,0000,0000,,Or we can look for survivors\Nin hazardous conditions Dialogue: 0,0:08:07.69,0:08:10.92,Default,,0000,0000,0000,,by looking at light reflected\Nthrough open windows. Dialogue: 0,0:08:11.60,0:08:17.48,Default,,0000,0000,0000,,Or we can build endoscopes that can see\Ndeep inside the body around occluders, Dialogue: 0,0:08:17.50,0:08:19.20,Default,,0000,0000,0000,,and also for cardioscopes. Dialogue: 0,0:08:19.22,0:08:21.59,Default,,0000,0000,0000,,But of course,\Nbecause of tissue and blood, Dialogue: 0,0:08:21.61,0:08:22.87,Default,,0000,0000,0000,,this is quite challenging, Dialogue: 0,0:08:22.89,0:08:24.83,Default,,0000,0000,0000,,so this is really a call for scientists Dialogue: 0,0:08:24.85,0:08:27.16,Default,,0000,0000,0000,,to start thinking about femto-photography Dialogue: 0,0:08:27.18,0:08:29.06,Default,,0000,0000,0000,,as really a new imaging modality Dialogue: 0,0:08:29.09,0:08:32.61,Default,,0000,0000,0000,,to solve the next generation\Nof health-imaging problems. Dialogue: 0,0:08:33.08,0:08:36.94,Default,,0000,0000,0000,,Now, like Doc Edgerton,\Na scientist himself, Dialogue: 0,0:08:36.96,0:08:39.27,Default,,0000,0000,0000,,science became art -- Dialogue: 0,0:08:39.29,0:08:41.95,Default,,0000,0000,0000,,an art of ultra-fast photography. Dialogue: 0,0:08:42.88,0:08:44.03,Default,,0000,0000,0000,,And I realized Dialogue: 0,0:08:44.06,0:08:47.50,Default,,0000,0000,0000,,that all the gigabytes of data\Nthat we're collecting every time, Dialogue: 0,0:08:47.52,0:08:49.94,Default,,0000,0000,0000,,are not just for scientific imaging. Dialogue: 0,0:08:49.96,0:08:55.50,Default,,0000,0000,0000,,But we can also do a new form\Nof computational photography, Dialogue: 0,0:08:55.53,0:08:58.06,Default,,0000,0000,0000,,with time-lapse and color coding. Dialogue: 0,0:08:59.15,0:09:00.62,Default,,0000,0000,0000,,And we look at those ripples. Dialogue: 0,0:09:00.64,0:09:01.80,Default,,0000,0000,0000,,Remember: Dialogue: 0,0:09:01.82,0:09:07.30,Default,,0000,0000,0000,,The time between each of those ripples\Nis only a few trillionths of a second. Dialogue: 0,0:09:08.60,0:09:10.81,Default,,0000,0000,0000,,But there's also something\Nfunny going on here. Dialogue: 0,0:09:10.83,0:09:13.63,Default,,0000,0000,0000,,When you look at the ripples\Nunder the cap, Dialogue: 0,0:09:13.65,0:09:15.84,Default,,0000,0000,0000,,the ripples are moving away from us. Dialogue: 0,0:09:16.85,0:09:18.76,Default,,0000,0000,0000,,The ripples should be moving towards us. Dialogue: 0,0:09:18.79,0:09:20.16,Default,,0000,0000,0000,,What's going on here? Dialogue: 0,0:09:20.18,0:09:26.98,Default,,0000,0000,0000,,It turns out, because we're recording\Nnearly at the speed of light, Dialogue: 0,0:09:26.100,0:09:28.89,Default,,0000,0000,0000,,we have strange effects, Dialogue: 0,0:09:28.91,0:09:32.17,Default,,0000,0000,0000,,and Einstein would have loved\Nto see this picture. Dialogue: 0,0:09:32.20,0:09:33.24,Default,,0000,0000,0000,,(Laughter) Dialogue: 0,0:09:33.26,0:09:36.31,Default,,0000,0000,0000,,The order at which events\Ntake place in the world Dialogue: 0,0:09:36.33,0:09:39.66,Default,,0000,0000,0000,,appears in the camera\Nsometimes in reversed order. Dialogue: 0,0:09:41.05,0:09:44.24,Default,,0000,0000,0000,,So by applying the corresponding\Nspace and time warp, Dialogue: 0,0:09:44.26,0:09:46.63,Default,,0000,0000,0000,,we can correct for this distortion. Dialogue: 0,0:09:48.61,0:09:52.96,Default,,0000,0000,0000,,So whether it's for photography\Naround corners, Dialogue: 0,0:09:52.98,0:09:56.98,Default,,0000,0000,0000,,or creating the next generation\Nof health imaging, Dialogue: 0,0:09:56.100,0:09:59.89,Default,,0000,0000,0000,,or creating new visualizations, Dialogue: 0,0:09:59.92,0:10:01.54,Default,,0000,0000,0000,,since our invention, Dialogue: 0,0:10:01.56,0:10:06.69,Default,,0000,0000,0000,,we have open-sourced all the data\Nand details on our website, Dialogue: 0,0:10:06.71,0:10:13.66,Default,,0000,0000,0000,,and our hope is that the DIY,\Nthe creative and the research communities Dialogue: 0,0:10:13.69,0:10:19.19,Default,,0000,0000,0000,,will show us that we should stop obsessing\Nabout the megapixels in cameras -- Dialogue: 0,0:10:19.22,0:10:20.50,Default,,0000,0000,0000,,(Laughter) Dialogue: 0,0:10:20.52,0:10:24.91,Default,,0000,0000,0000,,and start focusing\Non the next dimension in imaging. Dialogue: 0,0:10:25.61,0:10:26.92,Default,,0000,0000,0000,,It's about time. Dialogue: 0,0:10:27.34,0:10:28.49,Default,,0000,0000,0000,,Thank you. Dialogue: 0,0:10:28.51,0:10:35.38,Default,,0000,0000,0000,,(Applause)